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Threonine as the second limiting amino acid in barley for rowing-finishing pigs and growing rats Aw-yong, Lai Mon 1974

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THREONINE AS THE SECOND LIMITING AMINO ACID IN BARLEY FOR GROWING-FINISHING  PIGS AND GROWING RATS  by  LAI-MON. AW-YONG B.Sc.  (Agr.),  M c G i l l U n i v e r s i t y , 1972  A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n t h e Department of ANIMAL SCIENCE  We a c c e p t t h i s t h e s i s as conforming t o t h e rgjq^ii^ed s t a n d a r d  THE UNIVERSITY OF BRITISH COLUMBIA August, 1974  In p r e s e n t i n g t h i s an  further  for  s h a l l make it  fulfilment  this  freely  available  representatives. thesis for  Department of  of  the  requirements  Columbia,  I agree  reference and copying o f  this  for  that  study. thesis  purposes may be granted by the Head of my Department or It  financial  is understood that gain s h a l l  written permission.  Animal  The U n i v e r s i t y o f B r i t i s h Vancouver 8, Canada  Date  for  agree t h a t permission f o r e x t e n s i v e  scholarly  by h i s of  in p a r t i a l  advanced degree at the U n i v e r s i t y of B r i t i s h  the L i b r a r y I  thesis  August 2, 1974  Science Columbia  not  copying or  publication  be allowed without my  ABSTRACT  S u p p l e m e n t a t i o n w i t h graded l e v e l s o f t h r e o n i n e t o an a l l b a r l e y lysine diet  (0.75%  total lysine)  improved  the d a i l y gain, feed e f f i c i e n c y  and c a r c a s s q u a l i t y o f g r o w i n g - f i n i s h i n g p i g s . n i n e produced  An a d d i t i o n o f  0.10%  t h e optimum growth response i n t h e e x p e r i m e n t a l  threo-  animals.  No a d d i t i o n a l improvement was o b t a i n e d w i t h h i g h e r l e v e l s o f t h r e o n i n e o r t h r e o n i n e p l u s m e t h i o n i n e s u p p l e m e n t a t i o n o f the d i e t .  The  0.10%  c r i t e r i a w h i c h were  level  of  t h r e o n i n e s u p p l e m e n t a t i o n gave performance  to  those o b t a i n e d w i t h t h e b a r l e y - s o y b e a n c o n t r o l d i e t , e x c e p t t h e former  diet resulted i n s i g n i f i c a n t l y higher backfat added a t l e v e l s o f  0.15%  measurements.  comparable  Threonine  r e s u l t e d i n h i g h e r n i t r o g e n r e t e n t i o n than t h e  other b a r l e y - l y s i n e - t h r e o n i n e d i e t s .  N i t r o g e n r e t e n t i o n on t h i s d i e t d i d  not d i f f e r s i g n i f i c a n t l y from t h e c o n t r o l d i e t . resulted i n better protein u l t i l i z a t i o n  Barley-amino a c i d  diets  than b a r l e y - s o y b e a n c o n t r o l d i e t s .  F e e d i n g t r i a l s and m e t a b o l i s m t r i a l s i n d i c a t e d t h a t m e t h i o n i n e was n o t l i m i t i n g i n b a r l e y and t h a t t h r e o n i n e was t h e second l i m i t i n g amino a c i d .  Growth t r i a l s w i t h w e a n l i n g r a t s c o n f i r m e d t h e r e s u l t s o b t a i n e d i n the p i g n u t r i t i o n a l experiments.  R a t e x p e r i m e n t s i n d i c a t e d t h a t no  a d d i t i o n a l b e n e f i c i a l e f f e c t s were o b t a i n e d when l y s i n e l e v e l s were i n c r e a s e d from threonine. l e v e l of  0.75%  to  0.90%  even when supplemented  with additional  Results i n d i c a t e d that supplementation w i t h l y s i n e to a t o t a l 0.75%  and t h r e o n i n e a t a l e v e l o f  0.10%  resulted i n a highly  b a l a n c e d amino a c i d r a t i o f o r r a t s , and gave growth r a t e s w h i c h  approached  - iii  those o b t a i n e d on t h e c o n t r o l d i e t . diet with  0.20%  Supplementation of the b a r l e y - l y s i n e  t h r e o n i n e and a l l o t h e r e s s e n t i a l amino a c i d s r e s u l t e d i n  growth r a t e s and n i t r o g e n with  -  the c o n t r o l d i e t .  r e t e n t i o n s w h i c h resembled t h e r e s u l t s o b t a i n e d  The replacement o f t h e e s s e n t i a l amino a c i d m i x t u r e  w i t h g l y c i n e on an e q u a l n i t r o g e n b a s i s d i d n o t r e s u l t i n adequate r e t e n t i o n o r growth r a t e s .  nitrogen  - iv -  ACKNOWLEDGEMENTS  The a u t h o r w i s h e s t o e x p r e s s h i s g r a t i t u d e t o D r . R.M. Beames o f the Department o f A n i m a l S c i e n c e f o r h i s c o n s t a n t encouragement and dynamic guidance  throughout  the course of study.  In addition, h i s h e l p f u l  s u g g e s t i o n s d u r i n g t h e p r e p a r a t i o n o f the m a n u s c r i p t a r e g r a t e f u l l y acknowledged.  The w r i t e r i s g r a t e f u l t o Dr. W.D. K i t t s , Chairman o f t h e D e p a r t ment o f A n i m a l S c i e n c e , f o r t h e u s e o f n e c e s s a r y f a c i l i t i e s i n t h i s s t u d y . The a u t h o r a l s o w i s h e s t o thank Mrs. L. M a t h e r f o r h e r a s s i s t a n c e i n c a r r y i n g o u t t h e amino a c i d a n a l y s e s .  Thanks a r e a l s o extended t o  Dr. J.A. S h e l f o r d and Mrs. A.S. S a i t o f o r t h e i r a s s i s t a n c e s i n d a t a a n a l y s e s . The w r i t e r i s p a r t i c u l a r l y g r a t e f u l t o Mrs. Y.S. Choo who s p e n t c o n s i d e r a b l e time i n t h e t y p i n g o f t h i s m a n u s c r i p t .  F i n a n c i a l a s s i s t a n c e p r o v i d e d by t h e N a t i o n a l Research C o u n c i l i s gratefully appreciated.  - v  -  TABLE OF CONTENTS Page  LIST OF TABLES  xi  LIST OF FIGURES  xiii  I.  II.  INTRODUCTION  1  REVIEW OF LITERATURE  3  A.  ESSENTIAL AND NON-ESSENTIAL AMINO ACIDS  3  B.  DETERMINATION OF AMINO ACID REQUIREMENTS FOR GROWING ANIMALS USING GROWTH PERFORMANCE AND NITROGEN BALANCE  4  C.  METHODS OF DETERMINATION  OF AMINO ACIDS REQUIREMENTS  FOR GROWING PIGS BY DIET, TISSUE AND BLOOD ANALYSIS  6  a.  Methods Based on A n a l y s i s o f D i e t s  6  (1)  A n a l y s i s o f adequate d i e t s  6  (2)  Determination of the composition of an " i d e a l " p r o t e i n  b  Methods Based on T i s s u e and B l o o d A n a l y s i s  7 8 9  D.  VARIATION IN AVAILABILITY OF DIETARY PROTEIN  E.  METHOD OF ASSESSING AMINO ACID AVAILABILITY  10  a.  C h e m i c a l Methods  10  b.  M i c r o b i o l o g i c a l Methods  11  c.  Enzymic Methods  12  d.  Bioassays  12  F. G.  EFFECT OF PROTEIN DIGESTION AND ABSORPTION IN RELATION TO THE REQUIREMENT THE USE OF AMINO ACIDS IN P I G NUTRITION  13 15  - vi-  TABLE OF CONTENTS (Contd.) Page H.  •  (  AMINO ACID REQUIREMENT FOR GROWING-FINISHING PIGS  17  a.  General  17  b.  The Requirement f o r L y s i n e  17  c.  The Requirement f o r M e t h i o n i n e  20  d.  The Requirement f o r T h r e o n i n e  23  I.  AMINO ACID REQUIREMENT OF THE GROWING RAT  25  J.  SUPPLEMENTATION WITH AMINO ACIDS OF GRAIN-PROTEIN CONCENTRATE DIETS AND GRAIN ONLY  28  FACTORS ASSOCIATED WITH AMINO ACID SUPPLEMENTATION OF GRAINS  32  K.  a.  b.  c.  d.  III.  V a r i a t i o n o f G r a i n Amino A c i d s and A v a i l a b i l i t y  Profile 32  P r o t e i n L e v e l i n R e l a t i o n t o Amino A c i d Requirements  33  S i g n i f i c a n c e o f E s s e n t i a l and N o n - e s s e n t i a l Amino A c i d R a t i o  35  R e l a t i o n s h i p s between P r o t e i n and Energy Content o f a D i e t  35  e.  Amino A c i d s Imbalances and I n t e r a c t i o n s  38  f.  A n i m a l V a r i a t i o n : Age, Sex and G e n e t i c F a c t o r s  39  g.  F e e d i n g P r a c t i c e s : Ad L i b i t u m v s R e s t r i c t e d F e e d i n g  42  PIG EXPERIMENT I  43  A.  EXPERIMENTAL PROCEDURE  43  a.  General  43  b.  Design  43  - vii -  TABLE OF CONTENTS  (Contd.) Page  c.  Animals  44  d.  Diets  44  e.  Management  46  (i)  Housing  46  F e e d i n g method  46  Feed m i x i n g and s t o r a g e  46  (ii) (iii)  IV.  f.  Records  49  g.  Chemical A n a l y s i s  49  h.  C a r c a s s Measurements  49  i.  Calculations  50  j.  S t a t i s t i c a l A n a l y s i s o f Data  50  B.  RESULTS  52  C.  DISCUSSION  57  D.  CONCLUSION  68  PIG EXPERIMENT I I  70  A.  EXPERIMENTAL PROCEDURE  70  a.  General  70  b.  Animals  70  c.  Diets  71  d.  Management  71  (i) (ii)  Housing F e e d i n g method  •  71 71  - viii Page  V.  e.  Feces and U r i n e C o l l e c t i o n  73  f.  S t a t i s t i c a l A n a l y s i s o f Data  73  B.  RESULTS  75  C.  DISCUSSION  78  D.  CONCLUSION  83  RAT EXPERIMENT I  84  A.  EXPERIMENTAL PROCEDURE  84  a.  General  84  b.  Animals  85  c.  Diets  85  d.  Management  85  (i) (ii)  85  F e e d i n g methods  86  e.  Records  86  f.  Chemical A n a l y s i s  86  (i) (ii)  VI.  Housing  Feed  86  Carcass  86  g.  Calculations  87  h.  S t a t i s t i c a l Analysis  88  B.  RESULTS AND DISCUSSION  89  C.  CONCLUSION  95  RAT EXPERIMENT I I  96  A.  EXPERIMENTAL PROCEDURE  96  a.  96  General  - ix -  TABLE OF CONTENTS (Contd.) Page  VII.  b.  Animals  96  c.  Diets  97  d.  Management  98  e.  Records  98  f.  Chemical A n a l y s i s  98  g.  Calculations  99  h.  S t a t i s t i c a l Analysis  99  B.  RESULTS AND DISCUSSION  102  C.  CONCLUSION  109  RAT EXPERIMENT I I I  110  A.  EXPERIMENTAL PROCEDURE  110  a.  General  110  b.  Animals  110  c.  Diets  111  d.  Management  112  e.  Records  112  f.  Chemical A n a l y s i s  112  g.  Calculations  112  h.  S t a t i s t i c a l Analysis  112  B.  RESULTS AND DISCUSSION  115  C.  CONCLUSION  119  - x -  TABLE OF CONTENTS (Contd.) Page VIII. IX. X.  GENERAL CONCLUSIONS  120  LITERATURE CITED  122  APPENDIX  142  - x i-  LIST OF TABLES  E s s e n t i a l amino a c i d r e q u i r e m e n t s o f young r a t and growing p i g P e r c e n t a g e c o m p o s i t i o n o f d i e t s used i n P i g Experiments I & I I ( a i r dry b a s i s ) C o n t e n t o f e s s e n t i a l amino a c i d s and p r o x i m a t e c o n s t i t u e n t s o f b a r l e y and soybean m e a l on a dry m a t t e r b a s i s C o n t e n t o f e s s e n t i a l amino a c i d s and p r o x i m a t e c o n s t i t u e n t s i n d i e t s ( g amino a c i d / 1 0 0 g) i n P i g E x p e r i m e n t s I and I I Summary o f t h e e f f e c t o f t h e a d d i t i o n o f amino a c i d s t o b a r l e y on body w e i g h t g a i n , feed consumption (D.M.), f e e d c o n v e r s i o n (D.M.) and c a r c a s s measurement i n P i g Experiment I Comparison o f the e f f e c t s o f s u p p l e m e n t a t i o n w i t h amino a c i d s on mean d a i l y g a i n s and c a r c a s s measurements o f g i l t s and barrows Summary o f t h e e f f e c t s o f s u p p l e m e n t a t i o n o f b a r l e y w i t h amino a c i d s on a p p a r e n t d r y m a t t e r d i g e s t i b i l i t y , n i t r o g e n b a l a n c e , apparent n i t r o g e n d i g e s t i b i l i t y and on v a r i o u s n i t r o g e n r e t e n t i o n i n d i c e s E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on average d a i l y g a i n , f e e d c o n v e r s i o n e f f i c i e n c y and p r o t e i n e f f i c i e n c y r a t i o o f r a t s E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on c a r c a s s c h a r a c t e r i s t i c s o f r a t s P e r c e n t a g e c o m p o s i t i o n o f d i e t s used i n Rat Experiment I I ( A i r d r y b a s i s ) C o n t e n t o f e s s e n t i a l amino a c i d s o f each d i e t f o r R a t Experiment I I (g amino a c i d / 1 0 0 g mixed on a i r d r y b a s i s  feed)  - x i i -  LIST OF TABLES  (Contd.) Page  Table 12  13 14 15  16  17  E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on average d a i l y g a i n , f e e d c o n v e r s i o n e f f i c i e n c y and p r o t e i n e f f i c i e n c y r a t i o o f r a t s  103  E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on c a r c a s s c h a r a c t e r i s t i c s o f r a t s  107  P e r c e n t a g e c o m p o s i t i o n o f d i e t s used i n Rat E x p e r i m e n t I I I ( A i r d r y b a s i s )  113  Content o f e s s e n t i a l amino a c i d s of each d i e t f o r Rat E x p e r i m e n t I I I (g amino a c i d / 1 0 0 g mixed feed) on a i r d r y b a s i s  114  E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on average d a i l y g a i n , feed c o n v e r s i o n e f f i c i e n c y and p r o t e i n e f f i c i e n c y r a t i o o f r a t s  116  E f f e c t o f amino a c i d s u p p l e m e n t a t i o n o f low p r o t e i n b a r l e y on c a r c a s s c h a r a c t e r i s t i c s o f r a t s  117  - xiii  -  LIST OF FIGURES Figure  Page  1  G e n e r a l v i e w of m e t a b o l i s m cage  2  P i g i n the m o d i f i e d a d j u s t a b l e cage, h e l d w i t h b e l t and r u b b e r t u b i n g to m i n i m i z e u r i n e  72  loss  canvas 72  - 1 -  I.  INTRODUCTION  C e r e a l p r o t e i n i s w e l l known t o be low i n n u t r i t i v e p r i m a r i l y due t o a r e l a t i v e l y low l e v e l  value,  o f s e v e r a l e s s e n t i a l amino a c i d s  such as l y s i n e , t h r e o n i n e , m e t h i o n i n e and t r y p t o p h a n .  Promising  animal  growth r e s u l t s have been r e p o r t e d when t h e s e l i m i t i n g amino a c i d s a r e used as supplements f o r c e r e a l d i e t s . Soybean meal and f i s h m e a l a r e t h e most common p r o t e i n  concentrates  used as supplements f o r c e r e a l d i e t s , t h e i r b e n e f i c i a l e f f e c t a r i s i n g from t h e i r overcoming, b o t h the amino a c i d d e f i c i e n c i e s and t h e t o t a l d e f i c i e n c i e s i n the g r a i n .  nitrogen  The c o m p e t i t i o n between humans and l i v e s t o c k f o r  n a t u r a l p r o t e i n s o u r c e s has been a cause o f c o n c e r n f o r many y e a r s .  Natural  d i s a s t e r s such as d r o u g h t can e s c a l a t e p r i c e s and s e r i o u s l y i n t e r f e r e w i t h the economics o f swine p r o d u c t i o n .  I t has l o n g been hoped t h a t complete  dependence on c o n v e n t i o n a l p r o t e i n c o n c e n t r a t e s d u c t i o n o f amino a c i d s e i t h e r by f e r m e n t a t i o n possible solution.  can b e overcome.  or chemical  Hie pro-  synthesis offers a  A l t h o u g h some o f t h e s e s y n t h e t i c amino a c i d s a r e s t i l l  r e l a t i v e l y e x p e n s i v e a t p r e s e n t , an i n c r e a s e i n demand and thus l e v e l should r e s u l t i n a dramatic  production  reduction i n p r i c e , h o p e f u l l y to the l e v e l  where a d d i t i o n t o commercial l i v e s t o c k d i e t would be e c o n o m i c a l l y  B a r l e y i s one o f t h e major f e e d g r a i n s i n w e s t e r n Canada. important  attractive.  It is  t h a t t h e l i m i t i n g f a c t o r s i n b a r l e y p r o t e i n be e s t a b l i s h e d so t h a t  the most e c o n o m i c a l form o f s u p p l e m e n t a t i o n e i t h e r as c o n v e n t i o n a l p r o t e i n o r p u r e amino a c i d s can be p r a c t i c e d .  -  2 -  I t i s well established that l y s i n e i s the f i r s t l i m i t i n g amino acid i n barley as a feed for pigs.  Although methionine has been suggested  as the second l i m i t i n g amino acid by some workers, a large number of experiments have shown either no response to methionine or i n some cases, a growth depression.  In contrast, threonine, when tested as the second  l i m i t i n g amino acid, has shown a response with barley, wheat, r i c e , milo and sorghum.  Many recent reports have confirmed threonine as the second  l i m i t i n g amino acid i n grain i n the n u t r i t i o n of several monogastric species- including  man.  The objective of this study  was  to further evaluate under  p r a c t i c a l conditions the requirements of threonine  as the second l i m i t i n g  amino acid i n Peace River barley for growing-finishing pigs.  Hie  design  involved feeding graded l e v e l s of threonine i n a barley d i e t i n the presence of adequate l y s i n e and measuring growth performance, carcass quality and nitrogen balance.  P a r a l l e l studies were c a r r i e d out with rats  to further examine the n u t r i t i v e value of barley with l y s i n e , threonine mixture of other amino acids.  and  a  - 3 -  II.  A.  REVIEW OF  LITERATURE  ESSENTIAL AND NON-ESSENTIAL AMINO ACIDS  Amino a c i d s found i n p r o t e i n were c l a s s i f i e d by Rose (1938) i n t o two c a t a g o r i e s , the e s s e n t i a l and t h e n o n - e s s e n t i a l amino a c i d s , based on growth s t u d i e s w i t h r a t s . synthesized, at a l l , or at  E s s e n t i a l a r e those amino a c i d s w h i c h cannot be a  r a t e f a s t enough t o meet the m e t a b o l i c  r e q u i r e m e n t s , and t h e r e f o r e must be s u p p l i e d i n the d i e t .  Non-essential  amino a c i d s a r e those w h i c h can be s y n t h e s i z e d by a n i m a l s from normal constituents v i a transamination  reactions.  food  The number o f e s s e n t i a l amino  a c i d s v a r i e s w i t h s p e c i e s and the type o f p r o d u c t i o n d e s i r e d .  Those c o n s i -  dered to be e s s e n t i a l i n a l l mammalian s p e c i e s a r e v a l i n e , l e u c i n e , i s o l e u c i n e , threonine, methionine, l y s i n e , phenylalanine  and  tryptophan.  A r g i n i n e and h i s t i d i n e were f o r m e r l y i n c l u d e d i n t h i s l i s t .  I ti s  now c l e a r t h a t these amino a c i d s a r e s y n t h e s i z e d i n adequate q u a n t i t i e s t o meet minimum m e t a b o l i c  needs.  I n some s p e c i e s , f o r example, t h e r a t , b e t t e r  growth does o c c u r when these amino a c i d s a r e added t o t h e d i e t .  I n marked  c o n s t r a s t t o the mammalian s p e c i e s , the c h i c k cannot s y n t h e s i z e a r g i n i n e a t a l l and must o b t a i n a l l i t s r e q u i r e m e n t s f o r t h i s amino a c i d from t h e d i e t . In a d d i t i o n , the c h i c k apparently  cannot s y n t h e s i z e g l y c i n e , s e r i n e ,  glutamic  a c i d and p r o l i n e a t a s u f f i c i e n t l y r a p i d r a t e f o r the demands o f e a r l y growth ( A l m q u i s t , 1972) .  C y s t i n e and t y r o s i n e have been c o n s i d e r e d  as s e m i - e s s e n t i a l amino  a c i d s as they can be s y n t h e s i z e d o n l y from m e t h i o n i n e and  phenylalanine  -  respectively.  4  -  F o r example, when c y s t i n e i n t h e d i e t i s l o w , t h e amount o f  m e t h i o n i n e must be s u f f i c i e n t t o meet n o t o n l y t h e s p e c i f i c m e t h i o n i n e r e q u i r e m e n t , b u t a l s o p a r t of the c y s t i n e r e q u i r e m e n t . The b i o l o g i c a l ' v a l u e o f a p r o t e i n depends on t h e l e v e l o f each o f the e s s e n t i a l amino a c i d s p r e s e n t i s completely  All  and f a l l s t o a v e r y low l e v e l i f any one  absent.  the n o n - e s s e n t i a l amino a c i d s a r e found i n a n i m a l t i s s u e p r o -  t e i n , as they a r e r e q u i r e d i n the f o r m a t i o n  o f body p r o t e i n .  They may be  r e g a r d e d as p h y s i o l o g i c a l l y e s s e n t i a l and must be e i t h e r o b t a i n e d d i e t o r s y n t h e s i z e d by a n i m a l s from o t h e r amino a c i d s .  from the  I t has been  reported  t h a t g l u t a m i c a c i d , a n o n - e s s e n t i a l amino a c i d when e l i m i n a t e d f r o m a d i e t w i t h a low l e v e l o f c a s e i n o r s y n t h e t i c amino a c i d m i x t u r e s o u r c e o f n i t r o g e n , causes a marked d e p r e s s i o n nitrogen retention  (Harper,  1969;  i n growth r a t e and  Rama Rao e t a l . , 1960).  r o l e o f n o n - e s s e n t i a l amino a c i d s i s t h e i r amino a c i d s .  as the o n l y  Another  ' s p a r i n g ' a c t i o n on t h e e s s e n t i a l  The p r e s e n c e o f n o n - e s s e n t i a l amino a c i d s i n the d i e t reduces  the n e c e s s i t y o f s y n t h e s i z i n g them from the e s s e n t i a l amino a c i d s and Lougnon, 1968; A l m q u i s t , importance i n p r a c t i c a l  B.  1972).  (Rerat  T h i s s p a r i n g a c t i o n i s o f much  nutrition.  DETERMINATION OF AMINO ACID REQUIREMENTS FOR GROWING ANIMALS USING GROWTH PERFORMANCE AND NITROGEN BALANCE  The amino a c i d r e q u i r e m e n t s may be e s t i m a t e d Growth r a t e and f e e d c o n v e r s i o n  i n v a r i e t y o f ways.  e f f i c i e n c y a r e two commonly used  criteria.  - 5 -  However, these c r i t e r i a a r e n o t w i t h o u t d i s a d v a n t a g e s p a r t i c u l a r l y w i t h ad l i b i t u m f e e d i n g where i t i s d i f f i c u l t t o s p e c i f y whether t h e g a i n f o l l o w i n g the a d d i t i o n o f a s y n t h e t i c amino a c i d t o a d i e t i s due t o an improved t i t e o r a b e t t e r amino a c i d c o m p o s i t i o n p e r s e .  appe-  (R£rat ejt a l . , 1962) .  The d e t e r m i n a t i o n o f amino a c i d r e q u i r e m e n t s by t h e use o f growth performance  as a c r i t e r i o n , can b e improved upon by t h e a d d i t i o n a l i n f o r m a t i o n  o b t a i n e d from n i t r o g e n b a l a n c e measurements. has been w i d e l y used  technique  (Oslage et. al., 1966; Thorbek, 1969 and N i e l s e n ,  Another method f o r measuring analysis.  The n i t r o g e n b a l a n c e  1971).  nitrogen retention involves carcass  The amount o f n i t r o g e n r e t a i n e d i n a g i v e n i n t e r v a l can be e s t i -  mated from t h e d i f f e r e n c e between t h e t o t a l amount o f n i t r o g e n found b y a n a l y s i s a t s l a u g h t e r o f s p e c i f i c a l l y t r e a t e d a n i m a l s and t h a t c o n t a i n e d i n c o n t r o l animals slaughtered i n i t i a l l y . l a b o r a t o r y animal experiments  (Becker and H a r n i s c h 1958; R e r a t , 1961) and  has a l s o been employed i n t h e p i g l e t G r o v e s , 1965)  T h i s t e c h n i q u e i s w i d e l y used i n  (Manners and McCrea, 1963; Wood and  and t h e g r o w i n g - f i n i s h i n g p i g  ( O s l a g e , 1962).  Some d i s c r e p a n c i e s have been r e p o r t e d between t h e r e s u l t s o b t a i n e d by these two methods o f e s t i m a t i n g n i t r o g e n r e t e n t i o n where n i t r o g e n b a l a n c e has g i v e n s l i g h t l y h i g h e r r e t e n t i o n f i g u r e s than those o b t a i n e d by c a r c a s s analysis  ( N i e l s e n , 1971; O s l a g e , 1962; F u l l e r and Boyne, 1971).  -  C.  6  -  METHODS OF DETERMINATION OF AMINO ACIDS REQUIREMENTS FOR P I G S BY D I E T , T I S S U E AND  BLOOD A N A L Y S I S  E s t i m a t e s of s p e c i f i c widely  depending p a r t l y  of other d i e t a r y  amino a c i d  content of the d i e t .  Conversely,  on t h e l e v e l s  S e v e r a l methods, based on  adequate l e v e l s  of a  con-  different  Some o f them d e p e n d u p o n t h e a n a l y s i s  ( B e c k e r _et a l . , 1 9 5 4 a , b ) w h i c h s u p p l y g r a d e d l e v e l s  amino a c i d i n c o n j u n c t i o n w i t h  vary  e.g. the r e l a t i o n s h i p between the p r o t e i n  p r i n c i p l e s , have been employed. the d i e t s  requirements of animals  on t h e method o f a s s e s s m e n t and p a r t l y  constituents  t e n t and t h e c a l o r i c  GROWING  of  specific  o f v i t a m i n s and m i n e r a l s .  o t h e r methods r e l y upon t i s s u e a n a l y s i s ,  e.g.  W i l l i a m eta l .  (1954).  a.  Methods Based on A n a l y s i s o f D i e t s  The m e t h o d s u s e d f a l l d i e t s and  (1)  into  two g r o u p s :  (1) A n a l y s i s  (2) d e t e r m i n a t i o n o f the c o m p o s i t i o n o f an " i d e a l "  Analysis  protein.  of adequate d i e t s  The a m i n o a c i d r e q u i r e m e n t s a r e e s t i m a t e d diets  of adequate  on w h i c h s a t i s f a c t o r y  from the a n a l y s i s of  growth r a t e has been a c h i e v e d .  i m p r e c i s e m e t h o d o f e s t i m a t i o n b e c a u s e one may ments e x c e p t f o r t h a t o f t h e l i m i t i n g  This i s a  overestimate a l l  factor or factors  the r e q u i r e -  of the p r o t e i n s .  However, t h i s method has q u i t e o f t e n been u s e d f o r g r o w i n g p i g s R e r a t and L o u g n o n , 1 9 6 8 ) .  rather  ( E v a n s , 1958;  -  (2)  7 -  D e t e r m i n a t i o n o f t h e c o m p o s i t i o n o f an " i d e a l " p r o t e i n  The p r i n c i p l e on which t h i s group i s based c o n s i s t s o f an attempt to b u i l d an i d e a l l y b a l a n c e d p r o t e i n i n w h i c h t h e amino a c i d s p e r f e c t l y meet the r e q u i r e m e n t s w h i l e i n c l u d i n g a minimum amount o f a d d i t i o n a l n i t r o g e n . Two methods a r e used  :  i n the f i r s t case, the animals a r e f e d a mixture o f  s y n t h e t i c amino a c i d s as t h e o n l y n i t r o g e n s o u r c e o f t h e d i e t 1949).  ( M e r t z e_t a l . ,  T h i s method i s v e r y e x p e n s i v e and c o n s e q u e n t l y d i f f i c u l t t o a p p l y t o  large animals.  Most o f t h e p r o t e i n s o u r c e s i n t h e d i e t a r e n u t r i t i o n a l l y  limiting  i n one o r s e v e r a l amino a c i d s . An attemptwas made t o b a l a n c e t h e p r o t e i n r e q u i r e m e n t s by t h e a d d i t i o n o f s y n t h e t i c amino a c i d s ( R e r a t and Henry, 1 9 6 3 , Rosenberg, 1 9 5 9 ) .  The r e q u i r e m e n t can o n l y be d e t e r m i n e d  amino a c i d and i s e q u a l t o t h e amount o f t h i s amino a c i d performance  with that diet.  f o r the l i m i t i n g allowing the best  I n t h i s method, t h e b a s a l d i e t must b e w e l l  b a l a n c e d , and adequate i n a l l amino a c i d s e x c e p t t h e f i r s t l i m i t i n g , o t h e r w i s e p o t e n t i a l i t i e s o f growth o f t h e p i g cannot m a n i f e s t t h e m s e l v e s , and t h e r e q u i r e m e n t s d e f i n e d i n t h i s way a r e t o o l o w .  T h i s method can o n l y b e  a p p l i e d by means o f s u c c e s s i v e a p p r o x i m a t i o n .  Another l i m i t i n g f a c t o r may  appear  when t h e response  causes t h i s and subsequent protein i s obtained.  t o supplementation o f the f i r s t l i m i t i n g n u t r i e n t d e f i c i t s have t o be made up u n t i l an " i d e a l "  The a d d i t i o n a l q u a n t i t y o f s y n t h e t i c amino a c i d s must  n a t u r a l l y be c a l c u l a t e d a c c o r d i n g t o t h e o t h e r amino a c i d s p r e s e n t i n t h e d i e t and c o n s e q u e n t l y a c c o r d i n g t o n i t r o g e n l e v e l i n o r d e r t o a v o i d an imbalance  due t o e x c e s s .  -  b.  Methods Based on T i s s u e  8  and B l o o d  -  Analysis  W i l l i a m e_t a l . (1954) were a b l e t o demonstrate t h e r e l a t i o n s h i p s between amino a c i d r e q u i r e m e n t s and t i s s u e amino a c i d c o m p o s i t i o n o f t h e animals.  They showed t h a t t h e e s t i m a t i o n  o f amino a c i d r e q u i r e m e n t s  be b a s e d on t i s s u e a n a l y s i s a t d i f f e r e n t ages. amino a c i d s i n t h e t i s s u e were p o s t u l a t e d i n t h e "optimum" d i e t . Ericson  (1961) p o i n t e d  could  The r e l a t i o n s h i p s between  as b e i n g those w h i c h s h o u l d e x i s t  However, t h e r e has been c r i t i c i s m  o f t h i s method.  o u t t h a t the method c o u l d l e a d t o t h e e r r o r s o f  u n d e r e s t i m a t i o n by n o t t a k i n g i n t o account t h e d i f f e r e n c e s i n t h e r a t e o f r e l e a s e o f d i f f e r e n t amino a c i d s , the r a t e o f s y n t h e s i s knowing t h e p a r t i a l s y n t h e s i s  of p r o t e i n s ; w i t h o u t  o f amino a c i d s by t h e o r g a n i s m , n o r t h e i r  u t i l i z a t i o n f o r purposes o t h e r than t i s s u e development.  The  possible  s p a r i n g a c t i o n o f one amino a c i d on t h e r e q u i r e m e n t s o f o t h e r s has n o t been fully  evaluated.  Plasma amino a c i d (PAA) a n a l y s i s h a s a l s o been employed as a c r i t e r i o n t o e s t i m a t e t h e amino a c i d r e q u i r e m e n t s o f a n i m a l s . i s based on t h e o b s e r v a t i o n s  o f M o r r i s o n e^t a l . (1961) w i t h  e s p e c i a l l y o f Zimmerman and S c o t t (1965) w i t h c h i c k s .  The p r i n c i p l e  t h e r a t and  These w o r k e r s p r e s e n t e d  e v i d e n c e t h a t when an amino a c i d i s added i n graded l e v e l s t o a d i e t w h i c h i s d e f i c i e n t i n t h i s amino a c i d , t h e plasma c o n c e n t r a t i o n  o f t h i s amino a c i d  remains r a t h e r low and c o n s t a n t u n t i l the d i e t a r y r e q u i r e m e n t i s r e a c h e d . There i s a r a p i d and a p p r o x i m a t e l y l i n e a r i n c r e a s e  i n the c o n c e n t r a t i o n  t h i s l i m i t i n g amino a c i d i n t h e plasma when i n c r e a s i n g l e v e l s above d i e t a r y requirement  are fed,  of  - 9 -  D i e t a r y amino a c i d r e q u i r e m e n t s f o r a n i m a l s have been e s t i m a t e d by t h i s t e c h n i q u e i n c h i c k s (Zimmerman and S c o t t , 1965), r a t s ( S t o c k l a n d e t a l . , 1970) and p i g s ( M i t c h e l l et_ a l . , 1968b; Bravo e t a l . , 1970; K e i t h et^ a l . , 1972). technique.  V a r i a b l e r e s u l t s have been o b t a i n e d by employing  this  However, one must t a k e i n t o account t h e s i g n i f i c a n t v a r i a t i o n  i n the c i r c u l a t i n g amino a c i d l e v e l s between a n i m a l s and the e f f e c t o f f e e d i n g regimes the t a k i n g o f samples. time o f t h e l a s t f e e d  (Devilat et a l . ,  1970)  and e n v i r o n m e n t a l c o n d i t i o n s p r e c e e d i n g  The i n t e r v a l between the time o f s a m p l i n g s and the (Clark et a l . ,  1963; Combs e ^ a l . , 1967; M i t c h e l l e t  a l . , 1968b; O s t r o w s k i , 1969) i s i m p o r t a n t . duration of feeding i s important  I t i s e v i d e n t a l s o t h a t the  ( P i c k and Meade, 1970; M i t c h e l l e t a l . ,  1968b).  Most r e c e n t l y , an i n t e r e s t i n g new c r i t e r i o n was p r o p o s e d b y Brown and C l i n e (1974) .  They were a b l e t o demonstrated  that the t o t a l u r i n a r y  n i t r o g e n e x c r e t i o n l e v e l c o u l d be used as an i n d i c a t o r o f p r o t e i n quality  t o a s s e s s the amino a c i d r e q u i r e m e n t s o f swine and o t h e r non-  ruminant a n i m a l s .  The p r i n c i p l e i s based on t h e d e c r e a s e o f t o t a l u r i n a r y  n i t r o g e n o u t p u t when an a n i m a l i s f e d w i t h graded l e v e l s o f an e s s e n t i a l ..amino a c i d w h i c h i s d e f i c i e n t i n t h e d i e t .  D.  VARIATION IN AVAILABILITY OF DIETARY PROTEIN The t a s k o f p r e c i s e l y d e f i n i n g the amino a c i d  requirements  o f the v a r i o u s a n i m a l s p e c i e s has l o n g been c o m p l i c a t e d by a s s e s s i n g the a v a i l a b i l i t y o f t h e amino a c i d s i n the d i e t .  adequately It  has  - 10 -  been s t r e s s e d t h a t n o t a l l t h e amino a c i d s i n a p r o t e i n may be a v a i l a b l e t o s y n t h e s i z e the t i s s u e of the animal.  Complete u t i l i z a t i o n o f the amino a c i d  c o n s t i t u e n t s o f p r o t e i n s and o f those added o c c a s i o n a l l y i n t h e f r e e form i s o n l y p o s s i b l e under t h e two f o l l o w i n g c o n d i t i o n s : the same t i m e a t t h e s i t e o f s y n t h e s i s  they must be p r e s e n t a t  (Cannon e t a l . , 1947);  the r e s p e c t i v e  p r o p o r t i o n s o f the s u p p l y must be b a l a n c e d , a l l e x c e s s e s w i t h r e s p e c t t o needs r e s u l t i n g i n a c o r r e s p o n d i n g e x c r e t i o n . the requirements  C o n s e q u e n t l y , when d e t e r m i n i n g  f o r amino a c i d s from t h e c o m p o s i t i o n o f t h e d i e t , one must  take i n t o account a l l t h e f a c t o r s w h i c h may modify acids.  The a v a i l a b i l i t y  the a v a i l a b i l i t y  o f amino  o f amino a c i d s i n the d i e t may be d i m i n i s h e d when  the d i e t c o n t a i n s s u b s t a n c e s m o d i f y i n g the d i g e s t i b i l i t y o f t h e d r y m a t t e r or p r o t e i n o r when t h e p r o t e i n s t r u c t u r e i s changed due t o t r e a t m e n t such as the a p p l i c a t i o n o f h e a t d u r i n g p r o c e s s i n g .  Problems i n v o l v e d i n d e t e r m i n g a v a i l a b i l i t y  o f amino a c i d s have  been d i s c u s s e d by Grau and C a r o l l (1958) and Mauron (1961).  P r o g r e s s has  a l s o been made i n the p a s t decade i n the development o f p r o c e d u r e s amino a c i d a v a i l a b i l i t y . however, t h e p r o b l e m  t o assay  D e s p i t e p r o g r e s s h a v i n g been made i n some a s p e c t s ,  isstill  f a r from r e s o l v e d .  E.  METHOD OF ASSESSING AMINO ACID AVAILABILITY  a.  C h e m i c a l Methods  C h e m i c a l , m i c r o b i o l o g i c a l and enzymic methods as w e l l as b i o a s s a y s have been d e v e l o p e d  t o e s t i m a t e amino a c i d a v a i l a b i l i t y .  The most w i d e l y  - 11 -  used c h e m i c a l method i s t h a t developed by C a r p e n t e r lysine  ( C a r p e n t e r , 1960; Booth,  1971).  t o determine  available  The method depends upon t h e  r e a c t i o n o f the d i n i t r o f l u r o b e n z e n e w i t h the e-amino group o f l y s i n e i n i n t a c t p r o t e i n t o p r o d u c e a c o l o r e d l y s i n e d e r i v a t i v e w h i c h can be e s t i m a t e d after acid  hydrolysis.  In s p i t e of there being a  14-28%  overestimation of l y s i n e  a v a i l a b i l i t y when the method i s a p p l i e d t o the p u r e N - a - f o r m y l — N-e-deoxyf r u c t o s y l - d e r i v a t i v e s of l y s i n e , i t c e r t a i n l y remains t h e most a p p r o p r i a t e l a b o r a t o r y method f o r r a p i d l y ( F i n o t , 1973).  e v a l u a t i n g heat-damage to p r o t e i n s  No c h e m i c a l methods a r e a v a i l a b l e f o r the d e t e r m i n a t i o n o f  the a v a i l a b i l i t y  of t h e o t h e r i n d i v i d u a l amino a c i d s , w i t h the p o s s i b l e  e x c e p t i o n o f m e t h i o n i n e , which may be e s t i m a t e d as m e t h i o n i n e Methionine  s u l p h o x i d e w h i c h r e p r e s e n t s a form o f u n a v a i l a b l e m e t h i o n i n e  can be employed t o measure the m e t h i o n i n e  b.  sulphoxide.  availability  ( S m i t h , 1972).  M i c r o b i o l o g i c a l methods  M i c r o b i o l o g i c a l method f o r d e t e r m i n i n g a v a i l a b l e amino a c i d s have been w i d e l y u s e d , w i t h the method o f  F o r d (1960)  zymogenes b e i n g one o f the most p o p u l a r . the a v a i l a b i l i t y  Ford  who used  (1962)  o f seven amino a c i d s i n t h i s way :  was a b l e t o d e t e r m i n e  methionine, l e u c i n e ,  i s o l e u c i n e , a r g i n i n e , h i s t i d i n e , v a l i n e and t r y p t o p h a n . validity  Streptococcus  The u l t i m a t e  o f the method r e s t s upon i t s degree of c o r r e l a t i o n w i t h b i o l o g i c a l  assays i n v i v o . been o b t a i n e d  For methionine  good c o r r e l a t i o n s w i t h i n _ v i v o r e s u l t s have  ( C a r p e n t e r e t a l . , 1972).  - 12 -  c.  Enzymic Methods Mauron (1961) has been s u c c e s s f u l i n e v a l u a t i n g heat-damage i n  some m a t e r i a l , e s p e c i a l l y m i l k p r o d u c t s u s i n g enzymic methods. d i g e s t i o n i s g e n e r a l l y performed with' p e p s i n , f o l l o w e d by (Mauron et^ a i l . , 1955). in vitro digestion  A h i g h c o r r e l a t i o n was  of  The  pancreation  o b t a i n e d between the enzymic  Mauron e± _ a l . (1955) and  dinitroflurobenzene  method of C a r p e n t e r (1960) w i t h a s e r i e s of m i l k samples ( B u j a r d e t However,  the  determination  enzymic d i g e s t i o n method i s n o t s a t i s f a c t o r y i n the  al.,1967). routine  of a v a i l a b l e amino a c i d s because o f i n c o m p l e t e d i g e s t i o n i n  v i t r o n e c e s s i t a t i n g the use o f the unheated m a t e r i a l as a c o n t r o l , w h i c h i n p r a c t i c e would not always be p o s s i b l e .  d.  Bioassays  The  u l t i m a t e standard  b i o a s s a y w i t h the a n i m a l i t s e l f .  f o r measuring amino a c i d a v a i l a b i l i t y i s a The most w i d e l y used p r o c e d u r e s are b a s e d  on the growth r e s p o n s e of s m a l l a n i m a l s such as r a t s and  chicks  (Bragg et_ a l . , 1969;  Oh e_t a l . , 1972).  (Calhoun  P r o c e d u r e s u s i n g the r a t  o r the c h i c k have been developed f o r s e v e r a l amino a c i d s v i z . m e t h i o n i n e , i s o l e u c i n e and  tryptophan  using a s l o p e - r a t i o technique  ( P e l l e t t , 1963).  d e s c r i b e d by  Firnney  e t a l . , 1960)  (1964)  lysine,  Oh e t a l . (1972) determined  the  b i o l o g i c a l a v a i l a b i l i t y o f m e t h i o n i n e f o r the c h i c k i n v a r i o u s p r o t e i n supplements. soybean and and  35.0%  The  a v a i l a b l e m e t h i o n i n e c o n t e n t of meat, f i s h , b l o o d ,  f e a t h e r meal was respectively.  estimated  Using  t o be  91.1,  89.9,  66.3,  87.2,  rapeseed, 94.7  the c h i c k t o d e t e r m i n e a v a i l a b l e l y s i n e ,  C a r p e n t e r e t a l . (1972) c o n c l u d e d t h a t m a t e r i a l s cannot be ranked c o n s i s t e n t l y ,  -  but  that absolute  13  -  e s t i m a t e s o f m e t h i o n i n e a v a i l a b i l i t y s t i l l v a r y between  assay methods and f u r t h e r improvements a r e t h e r e f o r e n e c e s s a r y i f b i o a s s a y s a r e t o be u s e d f o r t h e c a l i b r a t i o n o f i n v i t r o p r o c e d u r e s .  S e v e r a l s t u d i e s on a v a i l a b i l i t y of p r o t e i n  ( O l s e n et_ JLL. , 1 9 6 8 ;  G i o v a n e t t i e t a l . , 1 9 7 0 ; Sauer, 1 9 7 2 ) i n d i c a t e t h a t c o n s i d e r a b l e  variation  e x i s t s among amino a c i d s i n t h e i r a v a i l a b i l i t y , a l t h o u g h amino a c i d a v a i l a b i l i t y depends on the type o f p r o t e i n b e i n g  studied.  I d e a l l y , d i e t s s h o u l d be f o r m u l a t e d a c c o r d i n g l a b i l i t y r a t h e r t h a n t o t a l amino a c i d c o n t e n t .  to amino a c i d a v a i -  However, t h i s i s n o t y e t  p o s s i b l e i n c o m m e r c i a l p r a c t i c e s i n c e no r a p i d method has been e s t a b l i s h e d to estimate a v a i l a b i l i t y .  Moreover, t h e v a r i a t i o n from b a t c h t o b a t c h i n  d i e t a r y components f u r t h e r c o m p l i c a t e s t h e p r o b l e m .  F.  EFFECT OF PROTEIN DIGESTION AND ABSORPTION IN RELATION TO  THE  REQUIREMENT  R e l e a s e o f amino a c i d s from p r o t e i n s depends on t h e h y d r o l y s i s o f p r o t e i n by p r o t e o l y t i c enzyme i n t h e g a s t r o - i n t e s t i n a l t r a c t . w h i c h amino a c i d s a r e r e l e a s e d  The r a t e a t  from ..pxp.feins may i n f l u e n c e the amino a c i d  r e q u i r e m e n t when d e t e r m i n e d b y the most common t e c h n i q u e s o f p r o v i d i n g l e v e l s o f f r e e amino a c i d s t o t h e b a s a l d i e t . release by  The d e l a y  graded  o f amino a c i d  may cause an u n d e r e s t i m a t e o f t r u e amino a c i d a v a i l a b i l i t y  provided  the p r o t e i n s o u r c e .  I t i s g e n e r a l l y a c c e p t e d t h a t i n t e s t i n a l h y d r o l y s i s i s the r a t e -  -  14  -  l i m i t i n g s t e p i n t h e a b s o r p t i o n o f the p r o t e i n .  However, t h e f r e q u e n t  lack  o f c o r r e l a t i o n between plasma amino a c i d l e v e l s and t h e q u a n t i t i e s o f amino a c i d s i n g e s t e d r a i s e s t h e q u e s t i o n o f whether r a t e o f r e l e a s e o f amino a c i d s i s t h e o n l y f a c t o r a f f e c t i n g t h e a v a i l a b i l i t y o f amino a c i d s . F a c t o r s such as m o l e c u l a r and  competition  w e i g h t , a f f i n i t y f o r d i f f e r e n t t r a n s p o r t system,  f o r a b s o r p t i o n on s i t e s have been r e p o r t e d  to a f f e c t rate  o f a b s o r p t i o n o f i n d i v i d u a l amino a c i d s  ( K r a t z e r , 1944; Delhumeau e t a l . ,  1962;  O r t e n , 1963; A d i b i et: a l . , 1967).  However, w h e t h e r t h e s e f a c t o r s  apply  t o a b s o r p t i o n o f amino a c i d s r e l e a s e d from p r o t e i n s has been  by s e v e r a l r e s e a r c h e r s 1970;  (Bergen and P u r s e r , 1968; C o u l s o n and Hernandes,  N i x o n and Mawer, 1970a, b ) . B e r g e n and p u r s e r  Mawer (1970a)  (1968)  and  N i x o n and  c o n c l u d e d t h a t t h e r e i s no d i f f e r e n t i a l r a t e o f a b s o r p t i o n  o c c u r r i n g among amino a c i d s from food d i g e s t a i n r a t and man. Mawer (1970b)  challenged  N i x o n and  r e p o r t e d t h a t t h e r a t e s o f a b s o r p t i o n o f t h e amino a c i d s  m i l k p r o t e i n and g e l a t i n  from  p r o t e i n were p r o p o r t i o n a l t o t h e c o n c e n t r a t i o n o f  amino a c i d s i n t h e p r o t e i n s e x c e p t f o r a r g i n i n e , a l a n i n e , p r o l i n e and glycine. although  G l u t a m i c a c i d and m e t h i o n i n e were absorbed a t a s i m i l a r i t has been r e p o r t e d i n e x p e r i m e n t s w i t h amino a c i d  ( O r t e n , 1963; A d i b i et_ al., 1967)  mixtures  t h a t g l u m a t i c a c i d was p o o r l y  r e l a t i v e to the r a p i d absorption of methionine.  rate  absorbed  The e v i d e n c e s u g g e s t s t h e  r a t e l i m i t i n g f a c t o r i n t h e d i g e s t i o n and a b s o r p t i o n o f a p r o t e i n i s t h e r a t e o f amino a c i d r e l e a s e from the p r o t e i n and n o t t h e r a t e o f a b s o r p t i o n of i n d i v i d u a l amino a c i d s . of amino a c i d s s h o u l d  Therefore,  determinations  take t h i s i n t o a c c o u n t .  on t h e r e q u i r e m e n t s  - 15 -  G.  THE USE OF AMINO ACIDS I N P I G NUTRITION  Beeson et_ a l .  (1948, 1949) were p r o b a b l y t h e f i r s t w o r k e r s t o  s e r i o u s l y attempt t o d e t e r m i n e t h e r e q u i r e m e n t s f o r amino a c i d s i n p i g nutrition.  When they used a p u r i f i e d d i e t i n c o m b i n a t i o n w i t h h y d r o l y z e d  f i s h p r o t e i n f o r young p i g s 0.01%) 0.40% gained  ( t h e d i e t was p r a c t i c a l l y f r e e o f t r y p t o p h a n  a r e m a r k a b l e r e s p o n s e i n growth was o b s e r v e d w i t h t h e a d d i t i o n o f  DL-tryptophan. 634 g  D u r i n g a four-week t r i a l ,  pigs f e d tryptophan  p e r day whereas t h e c o n t r o l b a s a l d i e t had z e r o g a i n .  The  r e s u l t c l e a r l y demonstrated t h e s i g n i f i c a n c e o f t r y p t o p h a n i n t h e d i e t . Beeson and h i s a s s o c i a t e s u s i n g a s i m i l a r b u t more found l a t e r on t h a t  0.2%  of p i g s ( S h e l t o n , 1951b).  precise  technique  D L - t r y p t o p h a n was s u f f i c i e n t f o r normal  growth  A t t h e same t i m e , e x t e n s i v e s t u d i e s on o t h e r  amino a c i d s were a l s o c a r r i e d o u t a t Purdue  (Beeson e t a l . ,  1948; M e r t z e t  a l . , 1949; Beeson e t a l . , 1953; M e r t z e t a l . , 1955) and a t C o r n e l l et_ a l . , 1950; B r i n e g a r et_ a l . , 1950a, b; K r o e n i n g jet a l . ,  B e c k e r and h i s a s s o c i a t e s B e c k e r et_ a l . ,  (Bell  1962).  (Becker e t a l . , 1955a, b; B e c k e r , 1959;  1963) a t I l l i n o i s a r e a n o t h e r group o f w o r k e r s t h a t have  done much t o e v a l u a t e t h e q u a n t i t a t i v e needs o f amino a c i d s i n t h e growing p i g . A number o f o t h e r s c i e n t i s t have a l s o c a r r i e d o u t such s t u d i e s , e.g. Evans (1958, 1960, 1962, 1963) a t Cambridge and C l a u s e n e t a l . (1959-1962) i n Copenhagen.  M o s t o f t h e e x p e r i m e n t s w h i c h have b e e n r e p o r t e d have b e e n conducted on w e a n l i n g p i g s ( e i g h t weeks o f a g e ) , a l t h o u g h s u c k l i n g p i g s have been used t o some e x t e n t .  The method w h i c h i s f r e q u e n t l y used t o a s s e s s  - 16 -  r e q u i r e m e n t s i s t o make up a b a s a l d i e t o f p u r i f i e d c a r b o h y d r a t e - r i c h i n g r e d i e n t s p l u s a p r o t e i n t h a t i s d e f i c i e n t i n one o r more o f the n a t u r a l l y o c c u r r i n g amino a c i d s .  I t has n o t been too d i f f i c u l t t o f i n d p r o t e i n s o u r c e s  low i n p a r t i c u l a r amino a c i d s , such as t r y p t o p h a n w h i c h i s low i n h y d r o l y z e d f e a t h e r m e a l , z e i n and g e l a t i n ; l y s i n e w h i c h i s low i n z e i n and c e r e a l p r o t e i n ; m e t h i o n i n e which i s low i n e x p e l l e r soybean meal and t h r e o n i n e w h i c h i s low i n r i c e p r o t e i n .  I f the p r o t e i n used i s a p o o r e r s o u r c e o f o t h e r  amino a c i d s than t h e one i n q u e s t i o n , a p r o p e r supplement  o f t h e o t h e r s must  be g i v e n .  C o n s e q u e n t l y , a d i e t w i t h a l l t e n e s s e n t i a l amino a c i d s ( f o r the r a t ) as the s o l e s o u r c e o f n i t r o g e n , e x c e p t ammonium c i t r a t e , was s u c c e s s f u l l y developed as e a r l y as 1950 by S h e l t o n e t a l . (1950) f o r w e a n l i n g p i g s . C l a u s e n e_t al. (1959-1962) conducted e x t e n s i v e s t u d i e s w i t h the a d d i t i o n of  one o r more amino a c i d s t o p r a c t i c a l d i e t s and demonstrated  the  b e n e f i c i a l e f f e c t o f amino a c i d s u p p l e m e n t a t i o n .  I t i s w e l l e s t a b l i s h e d t h a t the p r o t e i n q u a l i t y i n f e e d can be improved by a p p r o p r i a t e s u p p l e m e n t a t i o n w i t h the f i r s t - l i m i t i n g amino a c i d . However, t h e amount o f s u p p l e m e n t a t i o n t h a t can be used e f f e c t i v e l y i s governed m a i n l y by the c o n c e n t r a t i o n o f t h e second l i m i t i n g amino a c i d p r e s e n t i n t h e f e e d and the a v a i l a b i l i t y t o t h e o r g a n i s m .  Proper  supplementa-  t i o n i s a c h i e v e d when the amount o f the f i r s t - l i m i t i n g i s i n b a l a n c e w i t h the amount o f the second l i m i t i n g amino a c i d and.with the r e s t o f the p r o t e i n . A l l o t h e r n u t r i e n t s must, o f c o u r s e , be p r e s e n t e d i n the d i e t t o a s s u r e u t i l i z a t i o n o f the b a l a n c e d p r o t e i n .  full  - 17 -  H.  AMINO ACID REQUIREMENT FOR  a.  General  GROWING-FINISHING PIGS  The p r o t e i n r e q u i r e m e n t o f a n i m a l can be e x p r e s s e d more p r e c i s e l y i n term o f amino a c i d r e q u i r e m e n t .  A n i m a l s do n o t need p r o t e i n p e r se f o r  normal growth b u t r e q u i r e e s s e n t i a l amino a c i d s and an a d d i t i o n a l s o u r c e o f n i t r o g e n f o r n o n - e s s e n t i a l amino a c i d s y n t h e s i s to s u p p o r t n o r m a l  growth.  I n g e n e r a l , t h e r e i s an i n c r e a s e i n amino a c i d r e q u i r e m e n t s w h i c h i s d i r e c t l y p r o p o r t i o n a l t o the p r o t e i n and c a l o r i c c o n t e n t o f the d i e t (e.g.  b.  Bowland, 1962; B e c k e r et_ a l . , 1963; Clawson,  The Requirement  1967).  for Lysine  M e r t z et: a l . (1949) were t h e f i r s t to demonstrate an e s s e n t i a l f a c t o r i n the growing p i g d i e t . that  0.58%  l y s i n e was  protein diet. to v a r y 22%  B r i n e g a r et_ a l .  L a t e r , i t was  10.6%  crude  found t h a t the l y s i n e r e q u i r e m e n t seemed The f e e d i n g o f a  crude p r o t e i n d i e t t o w e a n l i n g p i g s i n d i c a t e d a r e q u i r e m e n t b a s e d 1.20%  lysine  ( B r i n e g a r e t a l . , 1950a, b ) .  (1958) r e p o r t e d a l y s i n e r e q u i r e m e n t o f p r o t e i n , and  0.9%  i n a d i e t of  0.7%  Change  i n a diet containing  20% p r o t e i n c o n t e n t .  12.8%  d i e t to be  .  and i n a  21%  p r o t e i n d i e t to be  0.95%  on  et a l . 10  or  Similarly,  McWard jet a l . (1959) showed the r e q u i r e m e n t o f l y s i n e i n a 0.71%  was  (1949) c o n c l u d e d  the r e q u i r e m e n t o f w e a n l i n g p i g s f e d a  d i r e c t l y w i t h the p r o t e i n c o n t e n t o f t h e d i e t .  growth d a t a o f  15%  that l y s i n e  protein  B e c k e r (1959) r e p o r t i n g e x p e r i m e n t s based on c h i c k s and p i g s  - 18 -  c o n c l u d e d t h a t the "requirement f o r each amino a c i d i s l i n e a r , b u t i s n o t a f i x e d p r o p o r t i o n of the p r o t e i n c o n t e n t o f the d i e t .  He i n d i c a t e d t h a t the  r e q u i r e m e n t f o r each amino a c i d , e x p r e s s e d as a p e r c e n t a g e o f the  total  d i e t a r y p r o t e i n d e c r e a s e s as the d i e t a r y p r o t e i n l e v e l i n c r e a s e s . ( 1 9 6 3 ) recommended  0.74%  l y s i n e f o r weanling pigs fed a  16%  Becker  protein diet.  I t has been s u g g e s t e d t h a t d i e t a r y c a l o r i c d e n s i t y can i n f l u e n c e amino a c i d r e q u i r e m e n t s .  P i g s e a t more o f a d i e t low i n c a l o r i c s t h a n o f  a d i e t of h i g h c a l o r i c d e n s i t y  (McWard e t a l . , 1959).  i n t a k e r e s u l t s when l i p i d i s added t o the d i e t  A decreased feed  (A.R.C., 1967).  I t therefore  seems l o g i c a l t h a t the amino a c i d r e q u i r e m e n t s s h o u l d i n c r e a s e w i t h i n c r e a s e i n d i e t a r y energy c o n c e n t r a t i o n . have been p r e s e n t e d by many workers  Results  i n a d i e t of K c a l ME/Kg.  22 Kg,  M i t c h e l l e t a l . , (1965b) 0.65%  2926 K c a l ME/Kg; b u t i t must be T h i s was  to support t h i s theory  ( M i t c h e l l et^ a l . , 1965b; L e r n e r , 1968;  B e l l and Voldeng,. 1968; R e r a t e t a l . , 1970). showed t h a t f o r an a n i m a l w e i g h i n g  an  l y s i n e was  0.80%  sufficient  i n d i e t of  3,718  c o n f i r m e d by R e r a t e_t a l . , (1970) and L e r n e r (1968)  by means o f d i e t s i n w h i c h t h e energy c o n t e n t was v a r i e d by a d d i t i o n o f v e r m i c u l i t e as an i n e r t d i l u e n t . M i t c h e l l (1965a) t o be  2.4  gm/Kcal ME.  t h a t the l y s i n e r e q u i r e m e n t f o r 3,330 K c a l DE/Kg  was  about  The l y s i n e r e q u i r e m e n t was  23  0.70%.  to  B e l l and V o l d e n g 57 Kg  c a l c u l a t e d by  (1968)  concluded  pigs fed a d i e t containing  B e l l (1965) a l s o demonstrated  i n c r e a s i n g the d i e t a r y l y s i n e l e v e l from  0.55  as i n c r e a s i n g the p r o t e i n l e v e l from  to  13  to 16%,  0.67%,  was  that  as e f f e c t i v e  where the response  c r i t e r i a were growth r a t e and e f f i c i e n c y o f f e e d u l t i z a t i o n .  - 19 -  The l y s i n e r e q u i r e m e n t v a r i e s a c c o r d i n g 1971).  to sex  (Henry e t a l . ,  Henry showed t h a t t h e l y s i n e r e q u i r e m e n t f o r female and c a s t r a t e d  male p i g s r a n g i n g from  20  o f a d i e t c o n t a i n i n g about  to  60 Kg  was  1.02  and  0.82% r e s p e c t i v e l y  3,400 K c a l DE/Kg.  The B r i t i s h A.R.C. p u b l i c a t i o n (1967) recommended d i e t a r y l y s i n e / 1 0 0 g a i r - d r y feed p i g s up t o (0.9-0.95  50 Kg  f o r s a t i s f a c t o r y performance  and t h e r e a f t e r about  and 0.7-0.75%  i n young  0.6-0.65 g/100 g a i r - d r y feed  of the d r y matter i n the d i e t r e s p e c t i v e l y ) .  c o n t r a s t s w i t h t h e N.A.S.-N.R.C. (1968) recommendation o f dry feed f o r 20-35 Kg  0.75-0.8 g  p i g s and  0.5%  0.7%  This  i n the a i r -  for finishing pigs.  The l y s i n e r e q u i r e m e n t s f o r maximum w e i g h t g a i n and f o r maximum l e a n meat o f f i n i s h i n g p i g s have n o t y e t been f u l l y d e f i n e d . (1966) and  N.A.S.-N.R.C. (1968) suggested t h a t a d i e t a r y l e v e l o f 0.50%  l y s i n e was adequate  f o r maximum r a t e o f body w e i g h t g a i n i n f i n i s h i n g p i g s .  More r e c e n t l y Brown e t a l . ( 1 9 7 3 a ) r e p o r t e d a r e q u i r e m e n t o f f o r maximum r a t e o f g a i n and diet containing  0.62%  3,501 K c a l ME/Kg  0.48%  lysine  f o r g r e a t e s t feed e f f i c i e n c y , u s i n g a  and  13.3% crude p r o t e i n .  agrees w i t h t h e r e s u l t s o f many i n v e s t i g a t i o n s on maximum g a i n  Becker e t a l .  This  result  l y s i n e requirements f o r  ( C a h i l l y ejt a l . , 1963; Lee e t a l . , 1967; Smith e t a l . , 1967).  However, D a v i d s o n e t a l . (1962) and M i t c h e l l e t a l . (1965a) r e p o r t e d t h a t the d i e t a r y l y s i n e l e v e l r e q u i r e d f o r maximum g a i n was a p p r o x i m a t e l y t h e same as t h a t r e q u i r e d f o r maximum f e e d e f f i c i e n c y .  The p r e d i c t e d  0.48  ± 0.02%  d i e t a r y l y s i n e r e q u i r e m e n t r e p o r t e d by Brown (1973a), was c o n s i d e r a b l y than  0.55%  r e p o r t e d by B e l l  and Voldeng  (1968).  lower  - 20 -  C a h i l l y et; a l . (1963) r e p o r t e d t h a t t h e l y s i n e r e q u i r e m e n t f o r m a x i m i z i n g p e r c e n t a g e o f l e a n c u t s and p r i m a l maximum g a i n .  However, H i n t z and Heitman (1967) found t h a t l y s i n e s u p p l e -  mentation of a tics.  c u t s was g r e a t e r than f o r  10.5% crude p r o t e i n d i e t d i d n o t a f f e c t c a r c a s s c h a r a c t e r i s -  More r e c e n t l y , Brown e t a l . (1973b) c o n c l u d e d t h a t t h e l y s i n e  ment f o r maximum c a r c a s s l e a n c o n t e n t was  0.51 ± 0.03%  s e c t i o n e d a r e a o f t h e l o n g i s s i m u s muscle was were corn-soybean  containing  From t h e r e s u l t s r e v i e w e d , i t appears  and f o r c r o s s -  0 ."60 ± 0.05%.  13.3% crude p r o t e i n and  require-  The d i e t s f e d  3,501 K c a l ME/Kg.  that the l y s i n e requirements f o r  maximum growth and f e e d e f f i c i e n c y a r e s l i g h t l y l o w e r than those f o r maximum carcass l e a n content.  c.  The Requirement  f o r Methionine  B e l l e_t a l . (1950) demonstrated rations.  E a r l y works by S h e l t o n e t a l . ( 1 9 5 1 a ) i n d i c a t e d t h a t t h e m e t h i o n i n e  requirement 50%  t h e need f o r m e t h i o n i n e i n swine  i n t h e abscence o f c y s t i n e was  0.6%  f o r w e a n l i n g p i g s and t h a t  o f t h e t o t a l s u l f u r amino a c i d r e q u i r e m e n t can be p r o v i d e d by c y s t i n e i n  a diet of  21%  crude p r o t e i n c o n t e n t s .  C u r t i n e t a l . (1952a, b) showed t h a t  when the c y s t i n e l e v e l was 0.38%, t h e r e q u i r e m e n t o f m e t h i o n i n e d i d n o t exceed 0.31%  i n a d i e t c o n t a i n i n g 22% crude p r o t e i n . Evans (1959, 1960) has r e p e a t e d l y  a c h i e v e d s a t i s f a c t o r y growth and f e e d c o n v e r s i o n e f f i c i e n c y up t o a l i v e w e i g h t of 45 Kg w i t h a low p r o t e i n d i e t c o n t a i n i n g a p p r o x i m a t e l y 0.5% m e t h i o n i n e p l u s c y s t i n e made up o f l o x j - p r o t e i n v e g e t a b l e foods p l u s The d i e t a r y crude p r o t e i n was  13  to  7%  white f i s h  meal.  15%. R 6 r a t e t a l . (1962) s u g g e s t e d  t h a t t h e o p t i m a l l e v e l o f t o t a l s u l f u r amino a c i d s f o r a h i g h r a t e o f growth  -  was  0.6  to  0.4  to  0.5%  0.7%  -  21  o f the d i e t f o r p i g s from  20  o f the d i e t f o r p i g s h e a v i e r o v e r  (1966) i n d i c a t e d  0.5%  to  60 Kg  60 Kg.  l i v e w e i g h t and  Becker et a l .  m e t h i o n i n e p l u s c y s t i n e t o be adequate  pigs of i n i t i a l weight  20 Kg  fed a d i e t containing  16%  f o r growing  protein.  They  found t h a t c y s t i n e c o u l d s a t i s f y f o r t y p e r c e n t o f the t o t a l s u l p h u r amino acid requirements.  R£rat and Henry (1970) demonstrated  o f s u l p h u r amino a c i d v a r i e s w i t h s e x . between  20  and  60 Kg  Female and c a s t r a t e d male p i g s  r e q u i r e d about  0.47%  amino a c i d r e s p e c t i v e l y i n a d i e t c o n t a i n i n g  Oestemer et_ a l . (1970) who  t h a t the requirement  and  0.52%  total  sulphur  3,420 K c a l DE/Kg.  conducted a s e r i e s o f e x p e r i m e n t s w i t h  growing swine t o d e t e r m i n e the c a p a c i t y o f opaque-2 c o r n t o p r o v i d e  methio-  n i n e s u g g e s t e d t h a t the m e t h i o n i n e p l u s c y s t i n e r e q u i r e m e n t o f growing from  21  to  40 Kg  was  somewhat l e s s than  r e p o r t e d by i n v e s t i g a t o r s p r e v i o u s l y c i t e d . 10.85%) c o n t a i n e d was  no  0.275, 0.279  and  0.227%  0.42  to  0.50%  pigs  o f the d i e t as  The c o r n d i e t s ( c r u d e p r o t e i n methionine plus c y s t i n e .  s i g n i f i c a n t improvement i n r a t e o f g a i n , g a i n / f e e d  There  or p r o t e i n e f f i -  c i e n c y r a t i o (PER) as a r e s u l t o f s u p p l e m e n t i n g the b a s a l c o r n d i e t w i t h 0.07,  0.14,  0.21  or  0.28%  DL-methionine.  A r e c e n t r e p o r t by K e i t h e t a l . (1972) i n d i c a t e d t h e m e t h i o n i n e r e q u i r e m e n t of growing p i g s (18 Kg) f r e e amino a c i d s t e c h n i q u e was  to be  0.46%  o f the d i e t .  employed i n t h i s e x p e r i m e n t .  More r e c e n t l y ,  Braude and E s n a o l a (1973) i n d i c a t e d t h a t the optimum p e r f o r m a n c e , r e t e n t i o n and c a r c a s s l e a n e s s was  o b t a i n e d w i t h about  m e t h i o n i n e p l u s c y s t i n e i n the d i e t .  The serum  4 gm/Kg  nitrogen (0.4%)  The recommended l e v e l s o f methionine.  - 22 -  p l u s c y s t i n e f o r growing p i g a r e g i v e n as  6 gm/Kg  (0.5%)  N.A.S.-N.R.C. (1968) r e s p e c t i v e l y .  o f t h e d i e t by  A.R.C. (1967) and  (0.6%)  and  5 gm/Kg  I n an a t t e m p t t o summarize the work a l o n e i n t h e l a s t two decades, i t may be c o n c l u d e d t h a t t h e m e t h i o n i n e p l u s c y s t i n e r e q u i r e m e n t f o r the growi n g p i g i s w i t h i n the ranges o f ranges from  12  to  by Oestemer et_ a l .  18%.  (1970).  0.4 t o 0.6% o f t h e d i e t when d i e t a r y p r o t e i n  The o n l y v a l u e o u t s i d e o f t h i s range was r e p o r t e d Braude and  E n a o l a (1973)  on t h e b a s i s o f t h e i r  s t u d i e s p o i n t e d o u t t h a t t h e l e v e l and s o u r c e o f d i e t a r y , p r o t e i n seems t o be important i n determining requirements.  T h e r e f o r e , an a c c u r a t e e s t i m a t e o f  requirements i s s t i l l v i r t u a l l y i m p o s s i b l e . Not much work has been done on t h e s u l f u r amino a c i d r e q u i r e m e n t s o f the f i n i s h i n g p i g .  R e r a t ejt a l . ,  (1962) r e p o r t e d t h a t t o t a l s u l f u r amino a c i d  r e q u i r e m e n t s o f f i n i s h i n g p i g s (> 60 Kg) was 0.4 t o 0.5% o f t h e d i e t . from t h e M i n n e s o t a s t a t i o n (Meade e t a l . ,  Studies  1966a, b) i n d i c a t e d t h a t t h e m e t h i o -  n i n e p l u s c y s t i n e r e q u i r e m e n t o f t h e f i n i s h i n g p i g i s e q u a l t o o r l e s s than t h e requirement o f  0.30%  o f t h e d i e t r e p o r t e d by B e c k e r e_t a l . ( 1 9 6 6 ) .  e t a l . (1966) r e p o r t e d t h a t m e t h i o n i n e s u p p l e m e n t a t i o n o f a t e i n corn-soybean m e a l d i e t c o n t a i n i n g  0.27%  12%  Welch  crude p r o -  methionine plus c y s t i n e  for-  t i f i e d w i t h c r y s t a l l i n e l y s i n e and t r y p t o p h a n d i d n o t i n c r e a s e n i t r o g e n r e t e n t i o n of the f i n i s h i n g p i g .  Most r e c e n t l y , Brown et^ a l .  (1974) i n d i c a t e d  t h a t t o t a l s u l f u r amino a c i d r e q u i r e m e n t s f o r maximum n i t r o g e n r e t e n t i o n were 0.17%  of a d i e t containing  14.1% p r o t e i n and 3,700 K c a l ME/Kg.  The v a l u e s  r e p o r t e d by Brown (1974) was s t r i k i n g l y lower than t h e v a l u e s r e p o r t e d by t h e previous i n v e s t i g a t o r  cited.  The a u t h o r s p o i n t s o u t t h a t no e s t i m a t e d v a l u e  - 23 -  o f t o t a l s u l f u r amino a c i d lower  than  0.17%  I t i s a p p a r e n t , t h e r e f o r e t h a t more work has  of the d i e t has been s t u d i e d . t o be done t o c l a r i f y  this  estimation.  d.  The Requirement f o r T h r e o n i n e  A r e q u i r e m e n t f o r t h r e o n i n e was  f i r s t demonstrated w i t h d i e t c o n t a i n -  i n g an amino a c i d m i x t u r e i n p l a c e o f p r o t e i n . d i e t supplemented t h r e o n i n e was  carbohydrate  w i t h amino a c i d s , S h e l t o n et_ _ a l . (1950) demonstrated t h a t  e s s e n t i a l as the p i g s l o s t w e i g h t when t h r e o n i n e was  from the d i e t . and  Using a p u r i f i e d  omitted  Beeson e_t al_. (1953) r e p o r t e d t h a t the maximum w e i g h t g a i n  f e e d c o n v e r s i o n e f f i c i e n c y of young p i g s were o b s e r v e d when d i e t a r y  t h r e o n i n e was protein).  p r o v i d e d up to a l e v e l of  The b a s a l d i e t was  amino a c i d s .  I t provided  o f the d i e t . the 2-3  day  o f the d i e t ( 3 %  o f the crude  based on maize and i n c l u d e d n i n e e s s e n t i a l  13.2%  e t a l . (1952) a l s o e s t i m a t e d  0.4%  crude p r o t e i n and  0.2%  threonine.  the t h r e o n i n e r e q u i r e m e n t of p i g s to be  Mertz 0.4%  S e w e l l e t a l . (1952) i n v e s t i g a t e d t h e t h r e o n i n e r e q u i r e m e n t o f o l d baby p i g u s i n g s e m i - p u r i f i e d d i e t s (25%  i n c l u d i n g c a s e i n and washed soybean p r o t e i n . minimum L - t h r e o n i n e  crude p r o t e i n )  They c o n c l u d e d  r e q u i r e m e n t of the p i g l e t was  0.90  g/100  that  the  g DM  diet.  B e c k e r e t a l . (1954a) w i t h a s e m i - p u r i f i e d d i e t based on d r i e d s k i m m i l k powder L - t h r e o n i n e was old pigs.  providing  12%  crude p r o t e i n c a l c u l a t e d t h a t  a satisfactory dietary concentration for  However,  nine requirements,  5  to  0.61% 9  week-  Evans (1958), u s i n g a s i m i l a r method to e s t i m a t e  threo-  c a l c u l a t e d the t h r e o n i n e c o n t e n t o f d i e t s w h i c h had  been  p r o v e n t o g i v e s a t i s f a c t o r y p e r f o r m a n c e , namely d i e t s c o n t a i n i n g  7%  fish  - 24 -  meal  20%  s  0.50%  ground n u t meal o r  respectively.  (1963) i n d i c a t e d up  to  36 Kg  liveweight.  15%  0.52, 0.55 and  F u r t h e r e x p e r i m e n t s conducted by t h e same a u t h o r  0.45%  d i e t a r y threonine  liveweight.  t o be adequate f o r w e a n l i n g p i g s  Less d i e t a r y t h r e o n i n e was needed a f t e r  R o b i n s o n and Lewis(1963) f e d a 95%  with l y s i n e , methionine, threonine, pig  soybean meal, t o be  36 Kg  b a r l e y d i e t supplemented  t r y p t o p h a n and i s o l e u c i n e f o r t h e g r o w i n g  and n o t e d t h a t t h e performance o f growth was e q u a l t o t h e c o n t r o l d i e t .  A l l these d i e t s c o n t a i n e d dietary  16.4%  crude p r o t e i n and p r o v i d e d  0.46%  of t o t a l  threonine. Lougnon and B r e t t e (1971) f e d wheat-soybean meal d i e t c o n t a i n i n g  14%  crude p r o t e i n supplemented w i t h l y s i n e , m e t h i o n i n e and d i f f e r e n t l e v e l  of t h r e o n i n e  to  17 Kg  s h o u l d n o t be below containing  pigs concluded that the threonine  0.50%  content of the d i e t  under r e s t r i c t e d f e e d i n g c o n d i t i o n s w i t h d i e t s  3,125 K c a l ME/Kg.  Henry and R.£rat (1970), u s i n g a s e m i - p u r i f i e d d i e t w i t h  10%  pro-  t e i n from a Norwegian h e r r i n g meal, s u p p l e m e n t a l by a f r e e amino a c i d s m i x ture concluded that the threonine Kg  l i v e w e i g h t was  Recently, requirement of  0.48%  r e q u i r e m e n t o f female p i g s o f  of a d i e t of  Sowers and Meade  15 Kg  0.33  ADG, G/F  and plasma f r e e  respectively.  threonine  0.39, 0.32  containing  crude p r o t e i n was based on c o r n , s a f f l o w e r m e a l , d r i e d  The b a s a l d i e t  s k i m m i l k and c r y s t a l l i n e e s s e n t i a l amino a c i d s e x c e p t t h r e o n i n e . a c i d was added t o i n c r e a s e  50  concluded the threonine  as c r i t e r i a t o be 10.4%  and  to  3,350 K c a l DE/Kg.  (1972a)  p i g s b a s e d upon  20  the crude p r o t e i n c o n t e n t t o  15%.  Glutamic  Another  - 25 -  experiment was conducted b y t h e same a u t h o r and c r y s t a l l i n e amino a c i d s .  (19 72b)  The b a s a l d i e t was  based on Opaque-2 c o r n  10.4% crude p r o t e i n .  The  t h r e o n i n e r e q u i r e m e n t was e v a l u a t e d b y i n c r e a s i n g t h e crude p r o t e i n l e v e l b y a d d i n g g l u m a t i c a c i d and k e e p i n g t h e e s s e n t i a l t o n o n - e s s e n t i a l amino acid  ratio  at  i n c r e a s e d from 10.4  to  1 : 1 . 0.35  It  was found t h a t t h e t h r e o n i n e r e q u i r e m e n t  t o 0.47% when d i e t a r y p r o t e i n was i n c r e a s e d from  15.0%. Sowers and Meade's r e p o r t s i n d i c a t e d t h a t adjustment f o r  r e q u i r e m e n t i s needed w i t h d i f f e r e n t l e v e l o f d i e t a r y p r o t e i n .  The N.A.S.-N.R.C. (1968) and A.R.C. (1967) recommendations f o r w e a n l i n g p i g s a r e about  I.  0.45 - 0.50%  of the d i e t .  AMINO ACID REQUIREMENT OF THE GROWING RAT A l t h o u g h t h e amino a c i d r e q u i r e m e n t s f o r growing r a t s have been  i n v e s t i g a t e d v e r y e x t e n s i v e l y and a r e r e l a t i v e l y w e l l e s t a b l i s h e d , s t i l l e x i s t i n the requirements l i s t e d i n v a r i o u s p u b l i c a t i o n s .  differences  The most  w i d e l y used and quoted f i g u r e s f o r t h e amino a c i d r e q u i r e m e n t s o f g r o w i n g r a t s a r e t h o s e r e p o r t e d by N.A.S.-N.R.C. (1972), and Rama Rao e t a l . ( 1 9 5 9 ) . The e s s e n t i a l amino a c i d r e q u i r e m e n t s o f growing r a t s p r e s e n t e d by N.A.S.-N.R.C. ( 1 9 7 2 ) , Rama Rao e t a l . (1959) and P i c k and Meade (1971) a r e summarized i n Table 1  for discussion.  The N.A.S.-N.R.C. (1972) recommended v a l u e s were  c o n c l u d e d from many s t u d i e s .  The r e p o r t by Rama Rao e t a l . (1959) was based  on a s e r i e s o f t h e i r own e x p e r i m e n t s i n w h i c h they gave t h e a n i m a l s a b a s a l diet containing  5%  c a s e i n t o w h i c h was added an amino a c i d m i x t u r e s v a r y i n g  i n t h e c o n t e n t o f each e s s e n t i a l amino a c i d .  The v a l u e s p r e s e n t e d were t h e  - 26 -  T a b l e 1 . E s s e n t i a l amino a c i d r e q u i r e m e n t s o f young r a t and growing p i g  Rama Rao e t a l . N.A.S.-N.R.C." P i c k and Meade (1959)  Rat  (1972)  (1971)  Rat  Rat  N.A.S.-N.R.C. (1968)  Pig (20-35 Kg)  Arginine  0.28  0.60  0.20  Histidine  0.21  0.30  0.18  Isoleucine  0.55  0.55  Leucine  0.69  0.75  Lysine  0.90  0.90  Phenylalanine  0.42  Phenylalanine + tyrosine  0.72  Methionine  0.36  0.50 0.60  0.70  0.70 0.50  0.80  0.59  0.60  0.50  Methionine + cystine  0.50  0.40  Threonine  0.51  0.50  Tryptophan  0.11  0.15  Valine  0.56  0.60  0.43  0.45 0.13  0.54  0.50  - 27 -  minimum l e v e l s on w h i c h maximum growth was o b t a i n e d .  The f i g u r e s o f P i c k  and Meade (1971) were o b t a i n e d by f e e d i n g a d i e t c o n t a i n i n g Opaque-2 maize supplemented w i t h amino a c i d s .  From t h e t a b l e , t h e v a l u e s r e p o r t e d by Rama Rao e t a l . (1959) and N.A.S.-N.R.C. (1972) a r e g e n e r a l l y i n agreement w i t h each o t h e r , e x c e p t t h a t the a r g i n i n e r e q u i r e m e n t i s c o n s i d e r a b l y h i g h e r i n t h e N.A.S.-N.R.C. recommendations.  However, t h e v a l u e s p r e s e n t e d  by P i c k and Meade (1971) a r e  g e n e r a l l y l o w e r e x c e p t f o r t h e v a l i n e r e q u i r e m e n t w h i c h i s i n agreement w i t h t h a t o f Rama Rao e t a l . (1959). S t o c k l a n d e_t a l . (1970 , 1971) r e p o r t e d t h a t t h e r e q u i r e m e n t o f young r a t s w i t h r e g a r d t o l y s i n e , p h e n y l a l a n i n e l a n i n e p l u s t y r o s i n e were  0.60, 0.38  and  0.69%  of the d i e t .  and p h e n y l a Stockland  e t j a l . (1970, 1971) agreed w i t h Rama Rao e t a l . (1959) on p h e n y l a l a n i n e  plus  t r y r o s i n e l e v e l s b u t derived a l y s i n e requirement only two-thirds that of Rama Rao et_ a l . (1959) and N.A.S.-N.R.C. (1972).  These a r e n o t i n c o n s e q u e n -  t i a l d i f f e r e n c e s b u t i t i s v e r y d i f f i c u l t t o say w h i c h may be more a c c u r a t e .  S i n c e t h e amino a c i d r e q u i r e m e n t s o f animals a r e i n t e r r e l a t e d , i t i s s t i l l i m p o s s i b l e , from e x i s t i n g d a t a , t o d e f i n e t h e l e v e l o f each e s s e n t i a l amino a c i d f o r o p t i m a l growth.  The p r o b l e m i s a l s o f u r t h e r c o m p l i c a t e d b y  o t h e r f a c t o r s such as t h e t o t a l n i f c r s g e n r e q u i r e m e n t ,  t h e e s s e n t i a l and non-  e s s e n t i a l amino a c i d r a t i o and t h e amino a c i d and energy r e l a t i o n s h i p s .  I t i s g e n e r a l l y r e c o g n i z e d t h a t t h e p r o t e i n and amino a c i d r e q u i r e ments d e c l i n e w i t h age  (Forbes  and Rao, 1959; H a r t s o o k and M i t c h e l l , 1956).  Because o f a l a c k o f any economic i n c e n t i v e t o p r o g r e s s i v e l y change t o cheap e r d i e t s w i t h a d v a n c i n g age i n most s p e c i e s t h e p r o b l e m has n o t been s t u d i e d  - 28 -  extensively.  Hartsook and M i t c h e l l (1956), by use of a carcass analysis  procedure, estimated that the requirements of protein and methionine plus cystine decline from about to  10%  and  0.42%  28%  and  respectively at  1.3%  respectively at  30 days of age  50 days of age.  The patterns of e s s e n t i a l amino acids required by the p i g (N.A.S.N.R.C, 1968) and the r a t (N.A.S.-N.R.C, 1972) as shown i n Table 1 are s i m i l a r except f o r arginine and l y s i n e .  However, the arginine requirements  of Rama Rao ej: a l . (1959) f o r the growing r a t are s i m i l a r to those of the p i g (N.A.S.-N.R.C, 1968), while the lysine l e v e l f o r the r a t given by Pick and Meade (1971) i s s i m i l a r to that f o r the p i g given by N.A.S.-N.R.C. (1968).  The laboratory r a t has been accepted as a s a t i s f a c t o r y p i l o t animal i n swine n u t r i t i o n a l research although requirements d i f f e r i n some respects and d i f f i c u l t y i s encountered.  J.  SUPPLEMENTATION WITH AMINO ACIDS OF GRAIN-PROTEIN CONCENTRATE DIETS AND GRAIN ONLY  Conventional p i g diets are based mainly on cereal grains such as corn, barley, wheat, oats and sorghum.  Cereals generally provide i n s u f f i c i e n t  e s s e n t i a l amino acids and sometimes i n s u f f i c i e n t nitrogen f o r the support of normal p i g growth. fishmeal  As a r e s u l t , protein supplements  such as soybean meal and  are normally added i n order to improve the protein content and to  counteract any e s s e n t i a l amino acid deficiency.  Since the protein concentrates are the most expensive components  -  in a pig diet, mixtures great  the p o s s i b l e replacement of  i n c o m m e r c i a l p r a c t i c e has  d e a l o f e f f o r t has  economical f e a s i b i l i t y diets  containing only  Lysine exception  of  grain plus minerals  1969;  Rerat  supplemented w i t h white  as  (Braude and  f o r the  growing p i g  coworkers  (1967a, b,  protein concentrate grain mixtures pigs  obtained Lewis  L o u g n o n , 1965;  lysine  been reported  tryptophan  lysine,  some o t h e r as  compared w i t h  to i n v e s t i g a t e the p o s s i b i l i t y  supplemented w i t h  lysine,  (1963) r e p o r t e d  markedly i n growing pigs  t h a t the  to g r a i n d i e t s  amino a c i d limiting  Miiller  equal  and of  to s i n g l e g r a i n or t o show  that  tryptophan  and  to that obtained  to  that  Robinson  efficiency  r e c e i v i n g b a r l e y d i e t s w h e r e l y s i n e and  t h a t t h e p e r f o r m a n c e was  in  of replacement  threonine,  feed  such  N.A.S.-N.R.C.  protein concentrates.  g r o w t h r a t e and  1960;  Ostrowski,  i n some c a s e s i s o l e u c i n e , g a v e a p e r f o r m a n c e e q u a l  with diets containing conventional  past  to improve p i g p e r f o r -  have been claimed  when a n a l y s i s a r e  In the  (Evans,  Rozman et^ a l . , 1 9 6 8 ;  Moreover, the a d d i t i o n of l y s i n e  the  performance  f o r g r o w i n g p i g s . M i i l l e r e t a l . (1967b) were a b l e  and  a r e added and  diets with  or  feeding.  demonstrated that  w i t h v a r i o u s e s s e n t i a l amino a c i d s  fed a cereal mixture  methionine,  for pig  A s e r i e s o f s t u d i e s were c o n d u c t e d by c , 1968)  and  grain diets  i s generally equally limiting.  has  A  amino a c i d i n c e r e a l g r a i n s w i t h  Lerman, 1970). B e s i d e s  (1968) r e q u i r e m e n t s .  amino a c i d  attention.  i n high  vitamins  l i t e r a t u r e has  fishmeal  t h r e o n i n e , m e t h i o n i n e and  cereals  and  and  Braude e t a l . , 1972).  mance  considerable  and  supplementing grain-based  1962;  ingredients with  o f u s i n g amino a c i d m i x t u r e s  corn, where tryptophan  J o n e s et_ a l . ,  reviewed  i s the most l i m i t i n g  i m p r o v e d by  these  been expended to i n v e s t i g a t e the n u t r i o n a l  d e c a d e , a v o l u m i n o u s amount o f can be  -  29  improved  methionine  with  a barley-  - 30 -  soybean c o n t r o l when t h e r e was a f u r t h e r a d d i t i o n o f i s o l e u c i n e and  DL-tryptophan,  DL-  DL-threonine.  M i i l l e r e_t a l . (1967b) w i t h w e a n l i n g p i g s o f  14-18 Kg  d i e t o f b a r l e y , wheat and o a t s p l u s an amino a c i d m i x t u r e t o  fed a cereal  50 Kg  live-  w e i g h t found t h a t the c o m b i n a t i o n o f l y s i n e and t h r e o n i n e ' h a d an e x t r a o r d i n a r i l y f a v o r a b l e e f f e c t upon g a i n s and f e e d c o n v e r s i o n . l y s i n e a l o n e enhanced g a i n s i n one case by  19%,  The supplement o f  i n a n o t h e r case by  The c o m b i n a t i o n o f l y s i n e and t h r e o n i n e i n c r e a s e d g a i n s by and by  92%  i n t h e second  trial.  59%  The c o m b i n a t i o n o f l y s i n e and  22%.  i n the f i r s t 0.02%  t r y p t o p h a n showed a p o s i t i v e r e s p o n s e , b u t caused a d e p r e s s i o n i n t h e 0.04% t r y p t o p h a n supplemented g a i n by  26-28%  g a i n by  35-42%.  level.  A supplement o f l y s i n e a l o n e i n c r e a s e d w e i g h t  whereas t h e c o m b i n a t i o n o f l y s i n e and t r y p t o p h a n i n c r e a s e d Another  t r i a l compared l y s i n e a l o n e and l y s i n e p l u s m e t h i o -  n i n e and showed no s i g n i f i c a n t d i f f e r e n c e i n g a i n , i n d i c a t i n g m e t h i o n i n e n o t to be t h e second  l i m i t i n g amino a c i d i n c e r e a l m i x t u r e s f o r t h e growing p i g .  Jensen e_t a l . (1965) u s i n g t h e f e e d i n g s t a n d a r d s o f B e c k e r et^ a l . (1963) i n d i c a t e d t h a t l y s i n e and p o s s i b l y m e t h i o n i n e were r e q u i r e d as a supplement t o sorghum f o r p i g s from  45 t o 90 Kg  l i v e w e i g h t , whereas l y s i n e  and t r y p t o p h a n were t h e r e q u i r e d amino a c i d s i n t h e s u p p l e m e n t a t i o n o f c o r n . The a d d i t i o n o f  0.25%  l y s i n e t o g r a i n improved  response to the f u r t h e r a d d i t i o n of methionine. i n d i c a t e d t h a t up t o  0.2%  t h e growth r a t e b u t gave no Beames e t a l . (1968) a l s o  l y s i n e a d d i t i o n improved  growth r a t e and f e e d  c i e n c y f o r t h e f a t t e n i n g p i g b u t improvement i n c a r c a s s  effi-  q u a l i t y was s l i g h t .  - 31 -  Bowland (1962) r e p o r t e d  that the a d d i t i o n o f  b a r l e y , wheat and soybean meal d i e t c o n t a i n i n g equivalent  t o one c o n t a i n i n g  16%  to a  13.6% p r o t e i n made t h e d i e t  p r o t e i n as measured b y g a i n and e f f i c i e n c y  o f feed u l t i z a t i o n i n p i g s over t h e 14 Kg t o  Soldevila  0.2% L - l y s i n e  44 Kg  body w e i g h t r a n g e .  and Meade (1964) i n d i c a t e d t h a t m e t h i o n i n e i s n o t  s e r i o u s l y l i m i t i n g i n b a r l e y f o r they s u g g e s t e d t h a t l y s i n e i s t h e f i r s t l i m i t i n g amino a c i d and p r o b a b l y t h r e o n i n e  Recently, barley only mentation. obtained  i s t h e second.  Re"rat and Henry (1969) a l s o r e p o r t e d  (10.1% crude p e o t e i n )  t h a t growth r a t e on  was n o t improved b y m e t h i o n i n e  supple-  Chung (1973) a l s o i n d i c a t e d t h a t no growth improvement was  by m e t h i o n i n e s u p p l e m e n t a t i o n o f a b a r l e y amino a c i d d i e t (10.3%  crude p r o t e i n ) .  L y s i n e and t h r e o n i n e have been r e p e a t e d l y f i r s t and second l i m i t i n g amino a c i d s i n r i c e 1959)  and b a r l e y  ( S u r e , 1955) f o r t h e r a t .  demonstrated t o be t h e  protein  Sure (1954) showed a l s o  wheat and r y e were d e f i c i e n t i n l y s i n e and t h r e o n i n e  also  (Pond e t a l . , 1958).  that  and t h a t r y e was a l s o  d e f i c i e n t i n v a l i n e . L y s i n e and t h r e o n i n e were r e p o r t e d milo  (Rosenberg e t a l . ,  t o be l i m i t i n g i n  T h r e o n i n e was s u g g e s t e d t o be t h e second  l i m i t i n g amino a c i d i n m i l o f o r r a t s (Pond e_t a l . , 1958).  Recently,  Veum _e_t a l _ . (1973) r e p o r t e d  t h a t normal and opague-2  c o r n d i e t s supplemented w i t h l y s i n e , m e t h i o n i n e and t r y p t o p h a n were d e f i c i e n t i n i s o l e u c i n e , v a l i n e , t h r e o n i n e when f e d t o g r o w i n g r a t s .  and p o s s i b l y  apparently phenylalanine  These r e s u l t s were s u p p o r t e d by those o f P i c k and  - 32 -  Meade (1971) who r e p o r t e d PER  t h a t e x c e l l e n t d a i l y g a i n , g a i n - f e e d r a t i o and  c o u l d be o b t a i n e d when a d i e t c o n t a i n i n g  supplemented w i t h methionine,  0.1%  0.12%  L-isoleucine,  L-phenylalanine,  0.18 t o 0.35% 0.14%  and  0.59 t o 0.65%  0.43%  threonine,  0.70%  0.36%  c o r n was  lysine,  t h r e o n i n e and  The f i n a l amino a c i d l e v e l o f t h i s d i e t was methionine + c y s t i n e ,  89.5% opaque-2  0.2%  0.08%  DL-  L-valine.  l y s i n e or l e s s ,  isoleucine,  0.40%  0.54%  valine  phenylalanine + tyrosine.  K.  FACTORS ASSOCIATED WITH AMINO ACID SUPPLEMENTATION OF GRAINS  a.  V a r i a t i o n o f G r a i n Amino A c i d s P r o f i l e and A v a i l a b i l i t y M a i z e , B a r l e y , wheat and sorghum a r e t h e most commonly used  grains i n p i g d i e t s .  Although these g r a i n s  cereal  a r e commonly l i m i t i n g i n t h e  e s s e n t i a l amino a c i d s , l y s i n e , t h r e o n i n e and m e t h i o n i n e , t h e q u a n t i t i e s o f t h e s e and o t h e r amino a c i d s v a r y from one t o a n o t h e r .  Accordingly,  the  o p t i m a l amino a c i d s u p p l e m e n t a t i o n o f g r a i n w i l l v a r y from g r a i n t o g r a i n . For examples, l y s i n e and t r y p t o p h a n a r e e q u a l l y and f i r s t l i m i t i n g i n maize s i n c e t h e e x p r e s s e d response f o r l y s i n e becomes minimum w i t h o u t t r y p t o p h a n addition  ( G a l l o and Pond, 1968; Pond and J o n e s , 1964).  However, i n b a r l e y ,  l y s i n e i s t h e most l i m i t i n g , f o l l o w e d by t h r e o n i n e w i t h m e t h i o n i n e p o s s i b l y third limiting  (Chung and Beames, 1972, 1974). Tryptophan i s adequate i n b a r l e y  a c c o r d i n g t o the N.A.S.-N.R.C. (1968) s t a n d a r d s f o r g r o w i n g p i g s . S i m i l a r t o b a r l e y , t h e f i r s t and second most l i m i t i n g amino a c i d s o f wheat a r e l y s i n e and threonine r e s p e c t i v e l y  (Shimada and C l i n e , 1974).  Variation i n availability  o f amino a c i d s i n d i f f e r e n t p r o t e i n s o u r c e s f u r t h e r c o m p l i c a t e t h e amino a c i d  - 33 -  supplementation  problem.  O l s e n et_ aJL. (1968) r e p o r t e d c o n s i d e r a b l e  i n amino a c i d a b s o r p t i o n from wheat b y — p r o d u c t s .  The  a b s o r p t i o n was  f o r c y s t i n e , g l u t a m i c a c i d , h i s t i d i n e and a r g i n i n e i n a l l p r o d u c t s whereas the l o w e s t p e r c e n t a g e a b s o r p t i o n was  ( C a r l s o n and B a y l e y , 1970;  S a u e r , 1972)  isoleucine.  highest tested  found f o r t h r e o n i n e ,  a l a n i n e , g l y c i n e , a s p a r t i c a c i d , m e t h i o n i n e and  variation  lysine,  Some r e s u l t s  have i n d i c a t e d t h a t the t r u e d i g e s -  t i b i l i t i e s of glutamic a c i d , p r o l i n e , •serine, l y s i n e , phenylalanine, and h i s t i d i n e i n soybean meal f o r young p i g s a r e h i g h e r threonine, methionine,  i s o l e u c i n e and g l y c i n e .  arginine  than those of a l a n i n e ,  G i o v a n e t t i e_t aJL. (1970) and  Sauer (1972) a l s o r e p o r t e d lower a v a i l a b i l i t i e s f o r l y s i n e , a l a n i n e , t h r e o n i n e and m e t h i o n i n e i n t r i t i c a l e , wheat and b a r l e y , i n c o n s t r a s t  to the h i g h  d i g e s t i b i l i t i e s of p r o l i n e , g l u t a m i c a c i d , a r g i n i n e , h i s t i d i n e and  phenylala-  nine . The e v i d e n c e s u g g e s t s t h a t amino a c i d r e q u i r e m e n t s s h o u l d expressed  on an a v a i l a b l e b a s i s and  be  t h a t the c o n t e n t of d i e t a r y components  s h o u l d be g i v e n on a s i m i l a r b a s i s .  b.  P r o t e i n L e v e l i n R e l a t i o n to Amino A c i d Requirements  The  t o t a l p r o t e i n c o n t e n t o f a d i e t may  on the amino a c i d r e q u i r e m e n t .  According  have an i m p o r t a n t  t o B e c k e r (1958) t h e r e q u i r e m e n t  f o r e s s e n t i a l amino a c i d s i n c r e a s e s w i t h the p r o t e i n c o n t e n t of the b u t the i n c r e a s e i s n o t i n d i r e c t p r o p o r t i o n . t i o n a l r e l a t i o n s h i p i s supported of i s o l e u c i n e , expressed  effect  The  diet,  argument o f d i s p r o p o r -  by an e x p e r i m e n t i n w h i c h the r e q u i r e m e n t  as a p e r c e n t a g e o f the n i t r o g e n o u s  d i e t , d e c r e a s e d as the d i e t a r y p r o t e i n i n c r e a s e d  (Becker  m a t t e r of  et a l . ,  the  1957).  - 34 -  T h i s was  f u r t h e r c o n f i r m e d f o r the l y s i n e r e q u i r e m e n t  and the t r y p t o p h a n r e q u i r e m e n t of growing p i g s  (McWard _et a l . , 1959)  (Boomgaardt and B a k e r , 1973) .  K r o e n i n g et^ al_. (1965) t h i n k t h a t the n e c e s s a r y c o n t e n t of s u l f u r amino a c i d s i n the d i e t v a r i e s i n t h e same d i r e c t i o n a s , b u t more s l o w l y than  t h e p r o t e i n c o n t e n t , e v e n when growth performances  Boomgaardt and Baker (1970, 1971)  a r e almost  identical.  i n d i c a t e d t h a t the l y s i n e and  t r y p t o p h a n r e q u i r e m e n t s o f young c h i c k s remain c o n s t a n t when e x p r e s s e d as a p e r c e n t a g e of the p r o t e i n .  These r e s u l t s c o n t r a d i c t t h e g e n e r a l l y  accepted  concept t h a t the r e q u i r e m e n t f o r an e s s e n t i a l amino a c i d d e c r e a s e s  linearly  as a p e r c e n t a g e o f the p r o t e i n and i n c r e a s e  c u r v i l i n e a r l y as a p e r c e n t a g e o f  the d i e t .  Rosenberg (1959) i n d i c a t e d t h a t the e f f e c t o f a change i n p r o t e i n l e v e l i s a problem of c o n s i d e r a b l e d o m e s t i c a n i m a l s range from  10%  p r o t e i n f o r the t u r k e y p o u l t . was p l o t t e d a g a i n s t  p r a c t i c a l importance because feeds f o r p r o t e i n f o r the f a t t e n i n g p i g t o  30%  P e r c e n t a g e p r o t e i n i n t h i s corn-soybean  diet  the p e r c e n t a g e o f amino a c i d i n the p r o t e i n f o r l y s i n e ,  m e t h i o n i n e and the c o m b i n a t i o n of m e t h i o n i n e and c y s t i n e i n corn-soybean diets.  As t h e l e v e l o f p r o t e i n was  i n the d i e t i n c r e a s e d , w h i l e acids decreased.  increased,  t h e r e l a t i v e amount o f l y s i n e  the r e l a t i v e amount o f t h e s u l f u r - b e a r i n g amino  Therefore, methionine d e f i c i e n c y i s l i k e l y  protein l e v e l increases.  t o o c c u r as the  Conversely, l y s i n e d e f i c i e n c y i s l i k e l y to occur  as the p r o t e i n l e v e l d e c r e a s e s  (Rosenberg e t a l . , 1959).  Accordingly,  the  adjustment o f most e s s e n t i a l amino a c i d . i s needed when the p r o t e i n l e v e l i s altered.  - 35 -  c.  S i g n i f i c a n c e of E s s e n t i a l and N o n - e s s e n t i a l Amino A c i d  Changes i n n i t r o g e n c o n t e n t w i t h an a l t e r a t i o n i n the s u p p l y e s s e n t i a l amino a c i d s .  Ratio  of the d i e t w i l l g e n e r a l l y be  not o n l y of e s s e n t i a l b u t  a l s o of non-  A d i e t composed of minimum l e v e l s of o n l y the e s s e n -  t i a l amino a c i d s s u p p o r t s  a s l o w r a t e o f growth o n l y  ( W r e t l i n d , 1949).  A d d i t i o n a l s o u r c e s of n i t r o g e n are r e q u i r e d f o r n o r m a l growth and physiological function. a c i d s (NEAA)  The  r a t i o of e s s e n t i a l  i n a d i e t f o r optimum growth has  S t u c k i and H a r p e r (1962) r e p o r t e d v a r y i n the r a t from retention.  4  They s t a t e  vorable r e s u l t s .  to  1  without  that e i t h e r wide  t h a t the  decreasing  d.  60%  obtained  to n o n - e s s e n t i a l amino  NEAA/EAA  r a t i o might  growth r a t e or  nitrogen  o r narrow r a t i o s would g i v e t h a t the h i g h e s t  unfa-  nitrogen  e q u a l amounts o f  R e c e n t l y , Henry and R£rat (1970)  i n d i c a t e d t h a t the b e s t growth p e r f o r m a n c e and t i a l amino a c i d s was  normal  r e c i e v e d much a t t e n t i o n .  o b t a i n e d when t h e d i e t c o n t a i n e d  e s s e n t i a l and n o n - e s s e n t i a l amino a c i d .  approximately  (EAA)  M i t c h e l l ejt a l . (1968a) r e p o r t e d  r e t e n t i o n of p i g s was  associated  the g r e a t e s t s p a r i n g of e s s e n -  from a w e l l b a l a n c e d d i e t f u r n i s h i n g  o f the t o t a l amino a c i d s i n the n o n - e s s e n t i a l  form.  R e l a t i o n s h i p s between P r o t e i n and Energy C o n t e n t o f a D i e t  The  u l t i z a t i o n o f p r o t e i n can o n l y be maximized when t h e r e i s  s u f f i c i e n t energy i n the d i e t from n o n - p r o t e i n ment o f the o r g a n i s m f o r c a l o r i e s .  The  s o u r c e s to s a t i s f y the r e q u i r e -  energy c o n t e n t  i n the d i e t i s o f  t i c a l i m p o r t a n c e f o r the s u c c e s s f u l amino a c i d s u p p l e m e n t a t i o n of a n i m a l Rosenberg _et a l . (1955) r e p o r t e d  t h a t no r e s p o n s e was  observed w i t h  the  crifeeds.  - 36 -  a d d i t i o n o f m e t h i o n i n e t o a corn-soybean meal d i e t f o r c h i c k s i n s p i t e o f the  f a c t that the f i r s t - l i m i t i n g  methionine.  amino a c i d i n t h e d i e t was c o n s i d e r e d t o b e  However, t h e c h i c k s responded t o t h e s u p p l e m e n t a l d i e t a r y  m e t h i o n i n e w i t h improved growth and feed e f f i c i e n c y when f a t was added t o the  diet.  T h i s e f f e c t was a l s o shown when f a t was r e p l a c e d by c a r b o h y d r a t e  ( B a l d i n i and Rosenberg, 1957). between  These s t u d i e s s u g g e s t a d i r e c t  relation  c a l o r i c d e n s i t y and the amino a c i d r e q u i r e m e n t s i n t h e d i e t .  studies a l s o i n d i c a t e d that three  caloric  levels  required  The  three  d i f f e r e n t l e v e l s o f m e t h i o n i n e f o r optimum performance o f t h e c h i c k (Baldini  and Rosenberg, 1955; B a l d i n i and R o s e n b e r g , 1957).  Baldini et a l .  (1957), Rosenberg and C u l i k ( 1 9 5 5 ) , and W i l l i a m s and Grau (1956)  a l s o showed  t h a t t h e c a l o r i c d e n s i t y i s one o f t h e f a c t o r s g o v e r n i n g t h e amino a c i d r e q u i r e m e n t s o f growing t u r k e y s , r a t s and c h i c k s .  The r e l a t i o n s h i p between of  a d i e t has  t h e p r o t e i n c o n t e n t and t h e energy c o n t e n t  a l s o b e e n s u b j e c t e d t o many s t u d i e s u s i n g p i g l e t s  1964; S t a n d i s h and Bowland, 1967) and  (Bowland,  the g r o w i n g - f i n i s h i n g p i g  (Sewell  e t a l . , 1956; A b e r n a t h y e t a l . , 1958; McWard ejt a l . , 1959; Henry and R d r a t , 1964; R o b i n s o n and L e w i s , 1964; R o b i n s o n e t a l . , 1964 ; R o b i n s o n , 1965a; Clawson, 1967; Cooke et a l . , 1972a, b ) . of  I n c r e a s e s i n the energy c o n t e n t  a d i e t reduce f e e d i n t a k e , b u t improve f e e d e f f i c i e n c y and i n some cases  a l s o improve growth r a t e . disappears  However, t h e b e n e f i t s o f i n c r e a s e d energy i n t a k e  when p r o t e i n i n t a k e i s i n s u f f i c i e n t .  C o n v e r s e l y , an i n c r e a s e d  p r o t e i n i n t a k e cannot be u l t i l i z e d e f f e c t i v e l y f o r body p r o t e i n s y n t h e s i s when the d i e t c o n t a i n s i n s u f f i c i e n t e n e r g y .  - 37 -  The s t u d i e s o f the r e l a t i o n s h i p s between l i p i d o f a d i e t by a number o f r e s e a r c h e r s et a l . ,  1965b; Re"rat e_t a l . , 1970)  content  and amino a c i d  (Anderson and Bowland, 1967;  content  Mitchell  showed t h a t the l e v e l o f amino a c i d s i n  the d i e t have to be i n c r e a s e d w i t h h i g h e r d i e t a r y l i p i d  content because of  the accompanying r e d u c t i o n i n f e e d i n t a k e .  I n terms of e n e r g y - l y s i n e r a t i o , R o b i n s o n ej; al_. (1964) t h a t the b e s t growth performance and c a r c a s s l e a n c o n t e n t r e c o r d e d when the r a t i o of 3,500  K c a l DE  to  Kg  concluded  f o r p i g s were  d i e t a r y l y s i n e was  approximately  a t a l l l e v e l o f energy c o n c e n t r a t i o n .  Lawrence (1971) i n d i c a t e d t h a t the narrow c a l o r i c / p r o t e i n / l y s i n e (CPL)  ratio diets  1  when compared w i t h wide  CPL  ratio diets  2  gave b e t t e r  growth r a t e s and e n e r g e t i c c o n v e r s i o n e f f i c i e n c i e s and h i g h e r c o l d c a r c a s s weights,  s m a l l e r back f a t d e p o s i t s and g r e a t e r p e r c e n t a g e o f l e a n and bone  b u t s m a l l e r p e r c e n t a g e of f a t i n the  The  carcass.  e f f e c t o f the i n t e r a c t i o n between p r o t e i n and energy  contents  of the d i e t on p i g s performance and c a r c a s s q u a l i t y has been i n v e s t i g a t e d by many w o r k e r s .  I n g e n e r a l , i t has been o b s e r v e d t h a t as the c o n c e n t r a t i o n o f  energy i n the f e e d i s r a i s e d , d i e t a r y p r o t e i n l e v e l needed f o r b e s t p e r f o r m a n c e increases.  1.  Growth r a t e and e f f i c i e n c y o f feed u t l i z a t i o n a r e g e n e r a l l y  D i g e s t i b l e energy : crude p r o t e i n r a t i o = 198 Crude p r o t e i n : L y s i n e r a t i o = 19.8  2.  : 1  D i g e s t i b l e energy : crude p r o t e i n r a t i o = 263 Crude p r o t e i n : L y s i n e r a t i o = 27.6  : 1  : 1  or  : 1 26.9  or : 1  273  : 1  - 38 -  improved by  r a i s i n g the n u t r i e n t c o n c e n t r a t i o n w h i l s t  carcass  q u a l i t y bene-  f i t s by an e l e v a t i o n of the p r o t e i n i n t a k e or of the o v e r a l l n u t r i e n t  A l t h o u g h energy and and  carcass  supply.  p r o t e i n i n t a k e i n f l u e n c e s growth performance  c h a r a c t e r i s t i c s of the growing p i g , many e x p e r i m e n t s f a i l  demonstrate any  s i g n i f i c a n t i n t e r a c t i o n between energy and  to  p r o t e i n i n terms  of these c r i t e r i a i n d i c a t i n g t h a t they a r e i n d e p e n d e n t from each  other  (Cooke e t a l . , 1972a, b; Lodge e t a l . , 1 9 7 2 ) . Cooke e t a l . (1972b) i n d i c a t e d a  t h a t p r o t e i n i n f l u e n c e d growth and were o v e r r i d d e n  carcass  lean content but  by i n t a k e of energy so t h a t t h e r e was  an i n c r e a s e d p r o t e i n i n t a k e c o u n t e r a c t i n g  t h a t the e f f e c t s  l i t t l e i n d i c a t i o n of  the a d v e r s e e f f e c t s of an  increased  energy i n t a k e on c a r c a s s q u a l i t y .  e.  Amino A c i d s  Imbalances and  Interactions  I t i s generally recognized a d e c r e a s e d growth r a t e and as a d e p r e s s i o n  a l o s s of a p p e t i t e .  i n growth ( o r any  have been r e p o r t e d  t h a t amino a c i d i m b a l a n c e s can r e s u l t i n  i n pigs  An i m b a l a n c e may  other adverse e f f e c t ) .  (Meade, 1956a, b; M i n e r e^t a l . , 1955),  t h e i r e f f e c t s have been s t u d i e d m o s t l y i n the r a t . two k i n d s o f i m b a l a n c e s were p o s s i b l e .  The  expressed  imbalances however,  H a r p e r (1961) i n d i c a t e d  f i r s t i s i n d u c e d by a d d i n g s m a l l  amount o f amino a c i d (but not the most l i m i t i n g one) and may  Nitrogen  be  to a low p r o t e i n d i e t  be overcome by s i m p l y s u p p l e m e n t i n g w i t h the l i m i t i n g amino a c i d s .  The second k i n d o f i m b a l a n c e s i s due mixture) being of g e l a t i n  may  ( H a r p e r , 1959).  t o t a l l y devoid  to the p r o t e i n s o u r c e ( o r amino a c i d  of a g i v e n amino a c i d .  d e c r e a s e the growth of r a t s u n l e s s More examples of  F o r example, a d d i t i o n  t r y p t o p h a n i s added  i m b a l a n c e s t u d i e s of the r a t can be  found  - 39 -  i n t h e r e p o r t by H a r p e r (1964).  A s e r i e s o f s t u d i e s by D'Mello and L e w i s  (1970a, b , c)  using  the c h i c k c l e a r l y demonstrated t h a t t h e r e q u i r e m e n t s f o r amino a c i d s i n animals a r e interdependent.  The s t u d i e s showed t h a t graded l e v e l s o f excess  d i e t a r y l y s i n e , l e u c i n e and t h e r o n i n e  increased  the q u a n t i t a t i v e requirements  o f a r g i n i n e , i s o l e u c i n e and t r y p t o p h a n r e s p e c t i v e l y . r e p o r t e d by D'Mello a diet increases  (1973)  A subsequent e x p e r i m e n t  i n d i c a t e d that r a i s i n g the i s o l e u c i n e l e v e l i n  t h e r e q u i r e m e n t s f o r l e u c i n e and v a l i n e .  These p a t t e r n s  of i n t e r a c t i o n s a r e r e f l e c t e d i n t h e plasma c o n c e n t r a t i o n o f l e u c i n e , i s o l e u c i n e and v a l i n e  (D'Mello,  1974).  The unique i n t e r a c t i o n between l y s i n e and  a r g i n i n e i n c h i c k n u t r i t i o n r e p o r t e d by D'Mello and Lewis (1970a,b,c) s u p p o r t s the o b s e r v a t i o n s  o f some o t h e r r e s e a r c h e r s  Smith and L e w i s , 1966).  ( O ' D e l l et_ a l . , 1958; J o n e s , 1964;  S i m i l a r l y , i n t e r r e l a t i o n s h i p s between s e v e r a l amino  a c i d s have been o b s e r v e d i n r a t s . These i n c l u d e i n t e r a c t i o n s between l e u c i n e , i s o l e u c i n e and v a l i n e a l . , 1967)  (Harper e t a l . , 1954, Benton j i t a l . , 1956; Rogers j2t  and between t h r e o n i n e  and t r y t o p h a n  (Salmon, 1954; M o r r i s o n and  H a r p e r , 1960; F l o r e n t i n o and Peason, 1962).  The  s p e c i f i c i t y o f i n t e r a c t i o n among l e u c i n e , i s o l e u c i n e and  v a l i n e i s f u r t h e r e x e m p l i f i e d by r e c e n t work w i t h t h e p i g (Oestemer e t a l . , 1973).  f.  A n i m a l V a r i a t i o n : Age", Sex and G e n e t i c  Factors  D i e t a r y p r o t e i n and amino a c i d s a r e u t i l i z e d f o r body p r o t e i n synthesis  ( a n a b o l i c f u n c t i o n ) and f o r maintenance.  I n t h e r a p i d l y growing  - 40 -  a n i m a l , the a n a b o l i c f u n c t i o n s account f o r a l a r g e p r o p o r t i o n o f the amino acid requirements.  C o n v e r s e l y , t h e r e p l a c e m e n t f u n c t i o n s d i c t a t e t h e amino  a c i d r e q u i r e m e n t s i n the mature a n i m a l .  As a r e s u l t , g r e a t e r abundance o f  h i g h q u a l i t y amino a c i d s a r e r e q u i r e d by young growing a n i m a l s than f o r mature a n i m a l s .  I n a d d i t i o n , amino a c i d r e q u i r e m e n t s p r o g r e s s i v e l y  decrease  increases.  as age  Oslage jet a l . (1966) r e t e n t i o n d e c r e a s e s w i t h age. e f f i c i e n c y was  about  to about  at  35%  52%  showed t h a t the e f f i c i e n c y of n i t r o g e n In t h e i r experiments, n i t r o g e n r e t e n t i o n  i n young a n i m a l s w e i g h i n g  100 Kg  and to  22%  at  r e s u l t s were o b t a i n e d by some o t h e r w o r k e r s R o b i n s o n , 1964).  25 Kg  and  160 Kg l i v e w e i g h t .  decreased  Similar  ( R e r a t and Henry,  1964;  E v i d e n c e f u r t h e r i n d i c a t e s t h a t amino a c i d a l l o w a n c e s  s h o u l d be reduced w i t h age.  Nitrogen u t i l i z a t i o n by s e x .  and thus n i t r o g e n " r e q u i r e m e n t s a r e a f f e c t e d !  I n g e n e r a l , females grow s l o w e r than c a s t r a t e d male and d i f f e r i n  body c o m p o s i t i o n .  However, a t e q u a l r a t e s o f growth and f e e d e f f i c i e n c y ,  females would have l e a n e r c a r c a s s e s i n d i c a t i n g h i g h e r n i t r o g e n r e t e n t i o n ' (Bowland and B e r g , 1959;  Robinson e t a l . , 1964;  Lodge jet a l . ,  C o n s e q u e n t l y , the r e s p e c t i v e needs f o r p r o t e i n and energy may to sex  (Bowland and B e r g , 1959; B l a i r e t a l . ,  1969b).  1972b). vary according  S i m i l a r l y , the amino  a c i d r e q u i r e m e n t s o f the female a r e d i f f e r e n t from those o f the male. Germann c^t al. (1958) showed t h a t females had optimum growth r a t e w i t h l e s s l y s i n e t h a n was n e c e s s a r y f o r m a l e s .  R 6 r a t and Henry (1970) i n d i c a t e d  the m e t h i o n i n e p l u s c y s t i n e r e q u i r e m e n t s of growing p i g s  (20 - 60  Kg)  that  -  v a r i e d w i t h sex.  41  Female p i g s needed  -  0.52%  d i e t whereas c a s t r a t e d p i g s r e q u i r e d o n l y  Bayley g i l t s to  and  of m e t h i o n i n e - c y s t i n e 0.47%  i n the  i n the  diet.  Summers(1968) i n d i c a t e d t h a t b o a r s responded more than  i n c r e a s e d p r o t e i n l e v e l i n the d i e t .  (1969a) and P i e r c e and Bowland (1972)  B e l l (1965), B l a i r e t a l .  were a b l e t o demonstrate t h a t  gilts  were more e f f i c i e n t c o n v e r t e r s of h i g h p r o t e i n d i e t s t h a n barrows w i t h  the  d i f f e r e n c e s r e d u c i n g as the p r o t e i n l e v e l s d e c r e a s e d .  I t has been r e p o r t e d t h a t t h e r e are i m p o r t a n t b r e e d s and w i t h i n the same b r e e d a s - r e g a r d s composition  ( H e t z e r e t a l . , 1963).  growth performance and body  The h i g h p r e s s u r e o f s e l e c t i o n t o  improve the g e n e t i c p o t e n t i a l f o r a l e a n e r c a r c a s s may amino a c i d r e q u i r e m e n t s .  d i f f e r e n c e s between  c r e a t e a change o f  To d a t e v e r y l i t t l e has been r e p o r t e d .  o f the g e n e t i c o r i g i n of the a n i m a l s  The  on n i t r o g e n r e t e n t i o n has been demon-  s t r a t e d by Anderson and Bowland (1967) who  r e p o r t e d t h a t the L a r g e W h i t e  p i g r e t a i n s n i t r o g e n b e t t e r than the L a r g e W h i t e x Lacombe  pig.  Bayley  Summers(1968) found a s i g n i f i c a n t i n t e r a c t i o n between s t r a i n o f p i g protein level.  effect  and  Lacombe and Y o r k s h i r e p i g s i n c r e a s e d l i v e w e i g h t g a i n w i t h  i n c r e a s e d p r o t e i n l e v e l from  13  to  16%  whereas no r e s p o n s e was  found  i n the Hampshire x Landrace and L a n d r a c e .  On  the b a s i s o f the above r e s u l t s recommendation f o r d i e t a r y  nitrogen should  t a k e b r e e d and s t r a i n i n t o a c c o u n t .  and  - 42  g.  Feeding P r a c t i c e s :  -  Ad L i b i t u m vs R e s t r i c t e d F e e d i n g  L e v e l of f e e d i n g i n f l u e n c e s the amino a c i d r e q u i r e m e n t s of p i g s . Ad l i b i t u m f e e d i n g i s commonly employed i n N o r t h A m e r i c a whereas r e s t r i c t e d f e e d i n g i s u s u a l l y p r a c t i c e d i n European c o u n t r i e s .  The p u r p o s e of  r e s t r i c t i n g f e e d i n t a k e i s to c o n t r o l the energy i n t a k e i n o r d e r the c a r c a s s q u a l i t y of the a n i m a l . ships, indicates that be a d j u s t e d to  according  A review  to improve  o f energy and p r o t e i n r e l a t i o n -  the l e v e l of e s s e n t i a l amino a c i d s i n the d i e t must t o the degree of f e e d r e s t r i c t i o n a p p l i e d .  R 6 r a t e t a l . (1971),  when energy i n t a k e i s r e s t r i c t e d to  80%  an ad_ l i b i t u m l e v e l , the i n c r e a s e i n n i t r o g e n and more p a r t i c u l a r l y a c i d s c o n t e n t must be about  10%  According of amino  to a v o i d m o d i f i c a t i o n of the p r o t e i n  synthesis.  I t has been recommended ( R e r a t , 1972)  t h a t amino a c i d r e q u i r e -  ment s h o u l d be e x p r e s s e d i n the form o f d a i l y amounts. c o u l d then be  transformed  T h i s recommendation  i n t o c o n c e n t r a t i o n s when f o r m u l a t i n g  diets.  -  III.  43  -  PIG EXPERIMENT I  A. • EXPERIMENTAL PROCEDURE  a.  General Many e x p e r i m e n t s have shown t h a t l y s i n e i s the f i r s t l i m i t i n g amino  a c i d i n b a r l e y as a f e e d f o r p i g s .  A l t h o u g h m e t h i o n i n e has been s u g g e s t e d  as the second l i m i t i n g amino a c i d by some w o r k e r s a l a r g e number o f e x p e r i ments have shown e i t h e r no response t o m e t h i o n i n e o r i n some c a s e s , a growth depression.  I n c o n t r a s t , t h r e o n i n e , when t e s t e d as the second l i m i t i n g amino  a c i d , has shown a r e s p o n s e w i t h b a r l e y  ( M i i l l e r ejt a l . ,  and w i t h sorghum  S e v e r a l r e c e n t r e v i e w papers  (Scrimshaw  (Pond e t a l . , 1958).  and A l t s c h u l , 1971)  1967c; Chung,  1973)  have c o n f i r m e d the w i d e - s p r e a d f i n d i n g of  t h r e o n i n e as the second l i m i t i n g amino a c i d i n s m a l l g r a i n s i n the n u t r i t i o n of s e v e r a l species, i n c l u d i n g  man.  The p r e s e n t e x p e r i m e n t i s d e s i g n e d t o e v a l u a t e the r e s p o n s e t o i n c r e a s i n g l e v e l s of t h r e o n i n e i n a d i e t o f b a r l e y p l u s adequate  lysine,  and to i n v e s t i g a t e the e f f e c t o f the a d d i t i o n o f m e t h i o n i n e to the d i e t c o n t a i n i n g the h i g h e s t l e v e l o f added t h r e o n i n e .  b.  Design The e x p e r i m e n t a l l a y o u t was  three-factor (diet —  t h a t of a c o m p l e t e l y randomized  t r e a t m e n t , s e x - male o r female and p e r i o d —  d e s i g n w i t h a f a c t o r i a l arrangement p e r each t r e a t m e n t c o m b i n a t i o n .  rep)  of t r e a t m e n t s and t h r e e o b s e r v a t i o n s  ( e . g . appendix page  146)  - 44 -  c.  Animals A t o t a l o f one hundred and e i g h t Y o r k s h i r e and Y o r k s h i r e x Land-  race  c r o s s p i g s were randomly a l l o c a t e d t o s i x d i e t a r y t r e a t m e n t s w i t h  sex numbers  (3  c a s t r a t e d males and 3  f e m a l e s ) t o a pen. These p i g s were  p l a c e d on t r i a l a t an average body w e i g h t o f  20 - 21 Kg  and t h e r e a f t e r  were weighed w e e k l y and were s l a u g h t e r e d when a body w e i g h t o f 85 Kg attained.  equal  was  The l a s t two p i g s i n a pen x^ere s e n t f o r s l a u g h t e r when t h e body  w e i g h t o f t h e h e a v i e r one exceeded  85 Kg.  D i e t s and pens were a l l o c a t e d  on a random b a s i s . d.  Diets The s i x d i e t s were f e d i n d r y mash form.  d i e t s i s g i v e n below. 1.  A d i s c r i p t i o n of the  I n g r e d i e n t s a r e l i s t e d i n Table 2  Barley-soybean  meal t o s u p p l y  0.75%  total lysine (control  diet) 2.  B a r l e y + 0.444%  L - l y s i n e HC1  to supply  0.75%  total  lysine  3.  B a r l e y + 0.444%  L - l y s i n e HC1  to supply  0.75%  total  lysine  to supply  0.75%  total  lysine  to supply  0.75%  total  lysine  to supply  0.75%  total  lysine  + 0.05% 4.  B a r l e y + 0.444% + 0.10%  5.  L - l y s i n e HC1  L-threonine  B a r l e y + 0.444% +0.15%  L - l y s i n e HC1  L-threonine  B a r l e y + 0.444% + 0.15%  6.  L-threonine  L - l y s i n e HC1  L - t h r e o n i n e + 0.10%  DL-methionine  - 45 -  T a b l e 2.  P e r c e n t a g e C o m p o s i t i o n o f D i e t s used i n P i g Experiments I & I I  ( A i r dry basis)  D i e t No  Ingredients 1  2  3  4  5  6  Barley  81.34  96.38  96.33  96.28  96.23  96.13  Soybean meal (45%)  15.60  -  -  -  -  -  L - l y s i n e HC1*  -  4.44  4.44  4.44  4.44  4.44  L-threonine *  -  -  0.05  0.10  0.15  0.15  DL-methionine *  -  -  -  -  -  0.10  Defluorinated rock phosphate  1.49  1.64  1.64  1.64  1.64  1.64  Limestone  0.57  0.54  0.54  0.54  0.54  0.54  Iodized  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50 •  0.50  salt  T r a c e m i n e r a l and v i t a m i n premix  The t r a c e m i n e r a l and v i t a m i n premix p r o v i d e d t h e f o l l o w i n g p e r kg o f r a t i o n  :  ZnS0 .7H 0,  B.H.T.  500 mg,  Vitamin  20 ug,  Riboflavin  4  2  pantothenate  Manganese  44 mg  as  MnSO^.H^O,  Vitamin A 2.9 mg,  Zinc  3085 I.U., Niacin  110 mg  Vitamin D  11 mg,  as 3  440 I.U.,  Calcium  11 mg ( 4 5 % e q u i v a l e n t ) .  * The L - l y s i n e HC1 was f e e d grade and was 98% p u r e , c o n t a i n i n g 78% L - l y s i n e . The L - t h r e o n i n e was p u r e , DL-methionine was 98% p u r e . A l l were produced by the A j i n o m o t o Co., Japan,  - 46 -  The amino a c i d c o n t e n t and c h e m i c a l c o m p o s i t i o n o f t h e b a r l e y and the soybean meal a r e shown i n T a b l e 3 d i e t i s l i s t e d i n Table 4  .  The amino a c i d c o m p o s i t i o n o f each  . A l l d i e t s were  f o r m u l a t e d t o c o n t a i n adequate  amounts o f a l l n u t r i e n t s known t o be r e q u i r e d f o r g r o w i n g - f i n i s h i n g p i g s e x c e p t f o r t o t a l p r o t e i n and amino a c i d c o n t e n t .  e.  Management (i)  Housing . T h i s e x p e r i m e n t was conducted a t t h e Swine R e s e a r c h U n i t , on t h e  U n i v e r s i t y o f B r i t i s h Columbia Campus.  The b u i l d i n g i s i n s u l a t e d , w i t h a i r  exhaust f a n s f i t t e d w i t h t h e r m o s t a t i c c o n t r o l s s e t a t  Pens a r e  2 5.6 m .  c o n c r e t e and p a r t i a l l y s l a t t e d and o f t o t a l a r e a (ii)  18.5° C.  F e e d i n g method P i g s were f e d t w i c e d a i l y a t  8:00 A.M.  and  1:00 P.M..  Feeding  was from t r o u g h s on an ad l i b i t u m b a s i s w i t h maximum a l l o w a n c e l i m i t e d t o 2.7 Kg  p e r day. Feed consumption  r e c o r d s were k e p t d a i l y .  Water was  s u p p l i e d ad l i b i t u m by d r i n k i n g n i p p l e .  (iii)  Feed m i x i n g and s t o r a g e A l l f e e d i n g r e d i e n t s were purchased and s t o r e d p r i o r t o t h e  commencement o f t h e e x p e r i m e n t out.  t o ensure a u n i f o r m d i e t c o m p o s i t i o n t h r o u g h -  The b a r l e y was s t o r e d i n t h e whole form.  r e q u i r e d i n 450 Kg  b a t c h e s by hammer m i l l i n g  D i e t s were p r e p a r e d as (7 mm  screen)  the b a r l e y  - 47 -  T a b l e 3.  Content o f e s s e n t i a l amino a c i d s and p r o x i m a t e c o n s t i t u e n t s o f b a r l e y and soybean meal on a dry matter b a s i s .  Concentration(g/100g Component  Barley  Soybean M e a l  Arginine  0.539  3.172  Histidine  0.247  1.621  Isoleucine  0.471  1.800  Leucine  0.870  4.089  Lysine  0.491  3.041  Methionine  0.200  0.709  (Cystine)  0.241  0.701  Phenylalanine  0.631  2.521  0.338  1.717  Threonine*  0.443  1.743  Tryptophan  0.749  0.126  Valine  0.808  2.052  (Tyrosine)  Crude p r o t e i n % (N x 6.25)  11.4  Ash %  2.5  Crude f i b r e %  6.72  Crude f a t %  3.19  d.m.)  51.3 6.3 5.7 1.49  U n c o r r e c t e d v a l u e from d e s t r u c t i o n o f a c i d h y d r o l y s i s ( B l a c k b u r n , 1968)  - 48 -  T a b l e 4.  Content o f e s s e n t i a l amino a c i d s and p r o x i m a t e c o n s t i t u e n t s i n d i e t s (g amino a c i d / 1 0 0 g) i n P i g E x p e r i m e n t s I and I I .  Diets Amino a c i d  _  (g/100 g A.D.) 1  2  3  4  5  6  Arginine  0. 82  0 .52  0 .52  0 .52  0 .52  0 .52  Histidine  0. 40  0 .24  0 .24  0 .24  0 .24  0 .24  Isoleucine  0. 58  0 .45  0 .45  0 .45  0 .45  0 .45  Leucine  1. 18  0 .84  0 .84  0 .84  0 .84  0 .84  Lysine  0. 75  0 .75  0 .75  0 .75  0 .75  0 .75  Methionine  0. 24  0 .19  0 .19  0 .19  0 .19  0 .29  (Cystine)  0. 27  0 .23  0 .23  0 .23  0 .23  0 .23  Phyenlalanine  0. 80  0 .61  0 .61  0 .61  0 .61  0 .61  0. 48  0 .33  0 .33  0 .33  0 .33  0 .33  Threonine  0. 56  0 .37  0 .42  0 .47  0 .52  0 .52  Tryptophan  0. 19  0 .11  0 .11  0 .11  0 .11  0 .11  Valine  0. 98  0 .78  0 .78  0 .78  0 .78  0 .78  Dry m a t t e r %  88. 55  87 .78  87 .61  88 .90  87 .58  87 .90  Crude p r o t e i n %  17. 58  11 .01  11 .36  11 .36  11 .32  11 .41  (Tyrosine)  - 49 -  and then m i x i n g i t w i t h the o t h e r i n g r e d i e n t s i n a v e r t i c a l mixer " A  to  10  f.  Records  5  minutes.  A l l p i g s were weighed t h e r e a f t e r a t weekly i n t e r v a l s . s p i l t f e e d , was g.  for  a t the commencement o f the e x p e r i m e n t  and  Weekly f e e d consumption, c o r r e c t e d f o r  recorded.  Chemical A n a l y s i s  A.O.A.C. methods  (1965)  were employed i n the a n a l y s i s of a l l  f e e d f o r m o i s t u r e , ash and crude p r o t e i n . mined by the method o f Van Soest ( 1 9 6 3 ) .  A c i d d e t e r g e n t f i b r e was  deter-  F o r amino a c i d a n a l y s i s , the  h y d r o l y z a t e s o f b a r l e y and soybean meal were p r e p a r e d by a c i d h y d r o l y s i s ( K o h l e r and P a l t e r , 1967)  e x c e p t f o r c y s t i n e and t r y p t o p h a n as these two  amino a c i d s a r e p o o r l y r e c o v e r e d from a c i d h y d r o l y z a t e s . was  d e t e r m i n e d as c y s t e i c a c i d by o x i d a t i o n h y d r o l y s i s  Therefore, cystine (Moore, 1963) .  M e t h i o n i n e was  d e t e r m i n e d as m e t h i o n i n e s u l f o n e from t h i s chromatogram.  Tryptophan was  d e t e r m i n e d by ion-exchange  chramotography  after  alkaline  h y d r o l y s i s by the method o f H u g l i and Moore ( 1 9 7 2 ) .  h.  C a r c a s s Measurements  D r e s s e d w e i g h t was measured on the h o t c a r c a s s ( w i t h h e a d ) .  The  ft K e l l e y Duplex M i l l Machinery, s i z e m f g. Co., S p r i n g f i e l d , Ohio.  220, s e r i a l 57364.  The Duplex  mill  - 50 -  c a r c a s s was then c h i l l e d a t muscle i n d e x skin)  4° C  f o r 96 hours  ( l e n g t h "A" x w i d t h "B")  and eye muscle a r e a , eye  and b a c k f a t t h i c k n e s s  ("C" w i t h o u t  d e t e r m i n e d on t h e s u r f a c e exposed by c u t t i n g t h e c a r c a s s a t r i g h t  a n g l e s t o i t s l e n g t h a t the j u n c t i o n o f t h e 7 t h and r i o r t o the d o r s o - s a c r a l j u n c t i o n f a t , minimum m i d d l e  8th vertebrae  (Buck e t a l . , 1962).  ante-  Maximum s h o u l d e r  f a t and maximum l o i n f a t were measured a c c o r d i n g t o t h e  Canada Department o f A g r i c u l t u r e (1968) methods.  i.  Calculations  Average d a i l y g a i n was d e t e r m i n e d as t h e b r e g r e s s i o n e q u a t i o n d e r i v e d from w e e k l y body w e i g h t 11  y " i s a e s t i m a t e d body w e i g h t ,  and  y = a + bx,  " x " days on t r i a l .  feed consumption and feed c o n v e r s i o n e f f i c i e n c y t o t a l body w e i g h t g a i n , b o t h e x p r e s s e d  value i n the l i n e a r where  The average d a i l y  ( t o t a l feed e a t e n d i v i d e d by  i n t h a same u n i t s ) were c a l c u l a t e d  f o r each pen. Carcass measurements were d e t e r m i n e d i n d i v i d u a l l y f o r each p i g .  j.  S t a t i s t i c a l A n a l y s i s o f Data The  d a t a were s u b j e c t e d t o a n a l y s i s o f v a r i a n c e u s i n g  UBC-MFAV  (Halm and L e , 1974)  computer program.  for missing values,  c a r c a s s measurements o f one m i s s i n g v a l u e was e s t i m a t e d  by m i s s i n g d a t a c a l c u l a t i o n  (Snedecor and Cochran, 1967) .  Two d i f f e r e n t a n a l y s e s were made. t o t a l back  fat,  "C"  back  S i n c e the program cannot compensate  fat,  F o r mean d a i l y g a i n , d r e s s i n g  percentage,  eye muscle i n d e x and a r e a , and  e x p e r i m e n t a l days, t h e i n d i v i d u a l t r e a t m e n t  combinations  ( d i e t , sex, period)  - 51 -  and t h e i r i n t e r a c t i o n s were i n v e s t i g a t e d  ( e g . page 1 4 7 ) .  F o r mean daily-  dry m a t t e r f e e d i n t a k e and f e e d c o n v e r s i o n e f f i c i e n c y , the o n l y f a c t o r was treatment  (diet)  w i t h t h r e e r e p l i c a t i o n s ( t h r e e groups o f  each) each ( e g . page 1 4 5 ) . Mean d a i l y g a i n , f e e d c o n v e r s i o n d r e s s i n g percentage as a c o v a r i a b l e .  6  animals  efficiency,  and days on t r i a l were a n a l y z e d w i t h s t a r t i n g  T o t a l back f a t ,  "C"  weight  back f a t , eye muscle a r e a and eye  muscle i n d e x were a n a l y z e d w i t h f i n a l body w e i g h t , average d a i l y g a i n and' c a r c a s s l e n g t h as c o v a r i a b l e s . Means from comparisons showing a significant  " F " v a l u e were t e s t e d u s i n g Tukey's t e s t  (1953).  - 52 -  B.  N u t r i e n t contents The  experimental  T a b l e 5.  of i n g r e d i e n t s and d i e t s a r e l i s t e d i n T a b l e  growth and  There was  RESULTS  carcass data analyses  a r e summarized i n  no d i f f e r e n c e i n average d a i l y i n t a k e among a l l t r e a t -  ments i n d i c a t i n g t h a t the e f f e c t of d i f f e r e n c e s were n o t due There was  no s i g n i f i c a n t e f f e c t of t r e a t m e n t s  barley-soybean  to a p p e t i t e .  on d r e s s i n g p e r c e n t a g e .  The  meal d i e t produced a s i g n i f i c a n t l y g r e a t e r growth r a t e than  a l l o t h e r d i e t s , e x c e p t f o r the 0.10%  t h r e o n i n e supplemented d i e t .  were no s i g n i f i c a n t d i f f e r e n c e s i n growth r a t e s between 0.15%  2.  t h r e o n i n e and  0.15%  threonine plus  0.10%  0.10%  There  threonine,  methionine d i e t s ,  but  a l l gave s u p e r i o r growth to t h a t o b t a i n e d on the d i e t c o n t a i n i n g no added threonine.  The  r a t e o f growth was  s i g n i f i c a n t l y g r e a t e r on the soybean-  c o n t r o l d i e t than on any o t h e r t r e a t m e n t s to  45 Kg  20  whereas no s i g n i f i c a n t d i f f e r e n c e s were o b s e r v e d between d i e t s  containing 0.10%  o v e r the body w e i g h t range  0.10%  threonine,  0.15%  m e t h i o n i n e a d d i t i o n s and  l i v e w e i g h t g a i n s from  45 Kg  t h r e o n i n e and  the b a r l e y - s o y b e a n  0.15%  threonine  control diet for  to f i n i s h i n g w e i g h t .  There were no s i g n i f i c a n t d i f f e r e n c e s i n terms of f e e d e f f i c i e n c y between the  0.10%  threonine  m e t h i o n i n e and  plus  e f f i c i e n c y was  0.10% similar  threonine,  0.15%  threonine,  i n diets containing  0.10%  a d d i t i o n of  on the b a s a l d i e t or the b a s a l p l u s  or greater  0.10%,  0.15%  threonine  and  0.15%  0.05%  conversion  0.15%  soybean c o n t r o l d i e t s .  t h r e o n i n e , a l l o f w h i c h produced a f e e d e f f i c i e n c y w h i c h was that obtained  plus  Feed added _  b e t t e r than  threonine.  threonine plus  The 0.10%  - 53 -  T a b l e 5.  Summary o f the e f f e c t . o f t h e a d d i t i o n of amino a c i d s t o b a r l e y on body w e i g h t g a i n , f e e d consumption (D.M.), feed c o n v e r s i o n  (D.M.) and c a r c a s s measurement i n  P i g Experiment I .  Treatment  1 2 3 4 5 s o y - c o n t r o l 0.75%lys B+ B+ B + ( B a s a l ) 0 . 0 5 % t h r 0 . 1 0 % t h r 0.15%thr  6 B+ 0.15%thr+ 0.10%met.  Starting wt.(Kg)  20.32  20.41  20.92  20.36  19.94  20.22  F i n a l wt.(Kg)  86.58  85.41  85.50  85.50  84.89  85.94  Mean d a i l y D.M. Feed i n t a k e (Kg)  SE A  Result of s i g n i ficance test**  1.943  1.821  1.839  1.911  1.823  1.856  ±0.015  146352  S t a r t to 45 Kg  0.648  0.466  0.522  0.556  0.536  0.565  ±0.013  164532  45 Kg to finish  0.729  0.603  0.619  0.744  0.687  0.686  ±0.018  145632  Start to finish  0.702  0.553  0.584  0.675  0.625  0.634  ±0.013  146532  -*  3.407  3.286  2.951  3.017  3.020  ±0.018  145632  Mean d a i l y g a i n (Kg)  D.M. Feed(Kg) Wt. g a i n (Kg)  /  5 J 1  Dressing %  78.59  79.37  80.15  78.18  79.04  79.26  ±0.63  326514  T o t a l back f a t (mm)  82.45  96.74  94.93  91.51  88.92  90.95  ±2.00  234651  Back f a t 40mm from m i d - l i n e 14.53  20.18  18.53  17.14  16.66  18.07  ±0.68  236451  Eye muscle i n d e x AxB (rnrn^)  4274  Eye muscle a r e a (mm ) z  Experimental period(days)  96.9  3432  3694  4001  3902  3740  ±78  145632  2414  ' 2645  2758  2658  2649  ±17  145632  ±1.83  146532  121.9  116.8  100.8  ' 106.6  106.5  S t a n d a r d e r r o r o f t r e a t m e n t means.  ** Treatment numbers n o t u n d e r s c o r e d by the same l i n e a r e s i g n i f i c a n t l y d i f f e r e n t a t the 5% l e v e l of p r o b a b i l i t y (Tukey, 1953).  - 54 -  m e t h i o n i n e t o t h e b a s a l d i e t improved feed c o n v e r s i o n e f f i c i e n c y by 12.9  and  12.8% r e s p e c t i v e l y .  There was no s i g n i f i c a n t treatment The b a r l e y - s o y b e a n  c o n t r o l p i g s had  the  e f f e c t on d r e s s i n g p e r c e n t a g e .  lowest t o t a l back f a t thickness  w h i c h was s i g n i f i c a n t l y d i f f e r e n t from t h e b a r l e y - l y s i n e b a s a l d i e t ment 2 ) , 0.05% t h r e o n i n e  (Treatment 3) and  0.10% t h r e o n i n e  (0.15%)  (Treatment 5) and  (Treatment 6) d i e t .  0.15%  threonine plus  2, 3  threo-  methionine  f o r t o t a l back f a t t h i c k -  The c a r c a s s l e n g t h had a s i g n i f i c a n t n e g a t i v e r e l a t i o n s h i p t o t o t a l  back f a t t h i c k n e s s . 40 mm  0.10%  4)  However no s i g n i f i c a n t d i f f e r e n c e s were o b s e r v e d  between the v a r i o u s b a r l e y - a m i n o a c i d t r e a t m e n t s ness.  (Treat-  (treatment  supplemented d i e t s b u t n o t s i g n i f i c a n t l y d i f f e r e n t from t h e h i g h e s t nine  15.5%,  A g a i n t h e c o n t r o l d i e t p r o d u c e d t h e l o w e s t back f a t  from t h e m i d - l i n e , b e i n g s i g n i f i c a n t l y l e s s than t h a t o f Treatments and  6  b u t n o t s i g n i f i c a n t l y d i f f e r e n t e from Treatments 4  and  5 .  No s i g n i f i c a n t d i f f e r e n c e s were o b s e r v e d among t h e f o u r d i e t s c o n t a i n i n g added t h r e o n i n e .  Back f a t  40 mm  from t h e m i d - l i n e i n Treatment 2 d i d  n o t d i f f e r s i g n i f i c a n t l y from measurements f o r Treatments 3,4 and 6 s i g n i f i c a n t l y h i g h e r than v a l u e s f o r Treatments  5  and  1.  b u t was  The c o v a -  r i a n c e a n a l y s i s showed t h a t c a r c a s s l e n g t h was s i g n i f i c a n t l y n e g a t i v e l y c o r r e l a t e d w i t h back f a t  40 mm  from t h e m i d - l i n e .  There was no d i f f e r e n c e i n eye muscle i n d e x between t h e c a r c a s s e s from p i g s on t h e c o n t r o l d i e t and those on Treatment 4 s i g n i f i c a n t l y h i g h e r than t h a t f o r a l l o t h e r t r e a t m e n t s .  b u t t h e former was There were no  s i g n i f i c a n t d i f f e r e n c e s among the t h r e o n i n e supplemented d i e t s .  The b a s a l  - 55 -  d i e t showed the l o w e s t eye muscle i n d e x though d i f f e r e n t from t h e means f o r Treatments observed  3  i t was n o t s i g n i f i c a n t l y  and  6.  S i m i l a r r e s u l t s were  f o r eye-muscle a r e a e x c e p t t h a t t h e c o n t r o l d i e t  s i g n i f i c a n t l y h i g h e r areas than a l l o t h e r t r e a t m e n t s .  produced  Covariance  analysis  i n d i c a t e d t h a t eye muscle i n d e x and eye muscle a r e a were s i g n i f i c a n t n e g a t i v e l y c o r r e l a t e d w i t h average d a i l y g a i n .  The mean d a i l y g a i n was s i g n i f i c a n t l y h i g h e r i n barrows than i n gilts.  G i l t s had c o n s i s t e n t l y s i g n i f i c a n t l y l o w e r b a c k f a t  measurements  and l a r g e r eye m u s c l e i n d i c e s and eye muscle areas than b a r r o w s . p e r c e n t a g e was n o t a f f e c t e d by s e x .  Dressing  There was no d i e t x sex i n t e r a c t i o n  i n mean d a i l y g a i n o r c a r c a s s measurements ( T a b l e 6 ) .  - 56 -  T a b l e 6.  Comparison o f t h e e f f e c t s o f s u p p l e m e n t a t i o n w i t h amino a c i d s on mean d a i l y g a i n s and c a r c a s s measurements  §  o f g i l t s and barrows  Gilt  Barrow  (s )  (sp  Mean D a i l y G a i n (Kg)  S i g n i f i c a n t F.. T e s t J.  2  0.612  0.646  ft*  C a r c a s s Measurement Dressing %  79.69  77.08  N.S.  T o t a l b a c k f a t (mm)  88.09  93.74  ft*  Back f a t 40 mm from mid l i n e (mm)  16.74  18.29  ft  3986  3696  ftft  2782  2589  ft*  2 Eye m u s c l e i n d e x (mm ) 2 Eye muscle a r e a (mm )  C a r c a s s measurements were a n a l y s e d w i t h f i n a l body w e i g h t , mean d a i l y g a i n and c a r c a s s l e n g t h as c o v a r i a b l e s . * **  P < 0.05 P < 0.01  '  -  - 57 -  C.  DISCUSSION  Based on the r e s u l t s o b t a i n e d i n t h i s f e e d i n g t r i a l , i t might be c o n c l u d e d t h a t the g r o w i n g - f i n i s h i n g p i g can p e r f o r m w e l l based on an  all-  b a r l e y l o w - p r o t e i n d i e t w i t h a d d i t i o n of an optimum l e v e l o f l y s i n e and t h r e o n i n e , p r o v i d i n g a d d i t i o n a l v i t a m i n s and m i n e r a l s a r e g i v e n . W i t h the 0.75%  lysine barley diet (basal d i e t ) ,  the a d d i t i o n of graded l e v e l s o f  L - t h r e o n i n e improved markedly the average d a i l y g a i n and f e e d c o n v e r s i o n e f f i c i e n c y o f the growing p i g . The 0.10%  t h r e o n i n e a d d i t i o n t o the b a s a l  d i e t produced r e s u l t s w h i c h were n o t s i g n i f i c a n t l y d i f f e r e n t  from t h e  r e s u l t s o b t a i n e d on the c o n v e n t i o n a l s o y b e a n - b a r l e y c o n t r o l d i e t that t h i s l e v e l of threonine  indicating  (0.47%) i n the d i e t , though l e s s than i n the  b a r l e y - s o y b e a n meal d i e t , w a s adequate f o r the growth performance o f g r o w i n g finishing pigs.  Chung and Beames  (1972)  r e p o r t e d t h a t an a l l b a r l e y  diet  i s f i r s t l i m i t i n g i n l y s i n e and t h a t t h r e o n i n e i s p r o b a b l y t h e secondl i m i t i n g amino a c i d . Chung (1973)  With  0.75%  t o t a l l y s i n e i n the l y s i n e - b a r l e y  observed a s i g n i f i c a n t response to  0.05%  diet,  threonine addition  i n growth and f e e d e f f i c i e n c y performance above the l y s i n e - b a r l e y d i e t .  The  r e s p o n s e o f t h r e o n i n e i n the p r e s e n t e x p e r i m e n t i s i n good agreement w i t h the r e s u l t s o f Chung and Beames ( 1 9 7 4 ) . to a  0.75%  However,  0.05%  l y s i n e d i e t i n the p r e s e n t e x p e r i m e n t improved t h e p i g p e r f o r -  mance b u t n o t s i g n i f i c a n t l y .  The r e a s o n i s p r o b a b l y because t h e t h r e o n i n e  l e v e l o f the b a r l e y used by Chung and Beames (1974) l e v e l i n the p r e s e n t e x p e r i m e n t . contained  threonine addition  0.24%  The b a s a l d i e t w i t h  was  l o w e r than the  0.75%  lysine  i n the e x p e r i m e n t o f Chung and Beames (1974) whereas i n  the p r e s e n t e x p e r i m e n t the t h r e o n i n e l e v e l was  0.37%  .  - 58 -  Supplementation  w i t h l y s i n e of a h i g h c e r e a l - d i e t has been shown  by s e v e r a l w o r k e r s to improve growth and feed e f f i c i e n c y Jones e t a l . , 1962; 1972).  E r i c s o n e t a l . , 1962;  B l o c h e t a l . (1972)  O s t r o w s k i , 1969;  from an experiment  (Evans,  1960;  Braude e t a l . ,  w i t h p i g s r e c e i v i n g an a l l -  b a r l e y d i e t showed t h a t b a r l e y p r o t e i n i s p o o r - q u a l i t y w i t h o u t amino a c i d supplementation. Although  Chung and Beames (1974) r e p o r t e d t h a t  content i n a barley-amino  a c i d d i e t was  0.90%  lysine  s i g n i f i c a n t l y d i f f e r e n t from  l y s i n e - b a r l e y d i e t as measured by growth r a t e and  0.75%  feed conversion e f f i c i e n c y  o f g r o w i n g - f i n i s h i n g p i g , the s i g n i f i c a n t d i e t x sex i n t e r a c t i o n i n d i c a t e d t h a t the h i g h e r l e v e l o f d i e t a r y l y s i n e c o n t e n t was b e n e f i c i a l o n l y f o r the gilts.  The  a d d i t i o n of  0.05%  threonine to  0.75%  lysine-barley  s i g n i f i c a n t l y improved t h e above p e r f o r m a n c e c r i t e r i a diets with only  0.75  and  0.90%  lysine.  diet  compared to t h e b a r l e y  T h i s suggested  that  0.75%  l y s i n e m i g h t be t h e o p t i m a l l e v e l f o r growth and f e e d e f f i c i e n c y , b u t t h a t t h r e o n i n e i s l i m i t i n g i n such a d i e t . growing be  0.70  The l e v e l o f d i e t a r y l y s i n e f o r the  and t h e f i n i s h i n g p i g x^as recommended by N.R.C.-N.A.S. (1968) t o and  0.50%  by A.R.C. ( 1 9 6 7 ) .  r e s p e c t i v e l y , and  0.75-0.80%  T h i s appears t o s u p p o r t t h a t  and  0.75%  0.6-0.65%  dietary lysine i s  adequate f o r the g r o w i n g - f i n i s h i n g p i g . M i i l l e r e t a l . (1967a) supplementation  o f a b a s a l c e r e a l d i e t had a  g a i n s and f e e d e f f i c i e n c y . ment i n g a i n s was However, with by  59%  demonstrated t h a t l y s i n e and  found  l a r g e f a v o r a b l e e f f e c t upon  With l y s i n e supplementation  to be  19%  i n one  case and  l y s i n e and t h r e o n i n e s u p p l e m e n t a t i o n ,  i n one t r i a l and  92% i n the o t h e r .  threonine  22%  alone, the improvei n another  case.  t h e g a i n s were improved  R e s p e c t i v e improvements i n  - 59 -  feed e f f i c i e n c y were  31  to  34%  .  M i i l l e r e^t a l .  i n g r o w i n g - p i g d i e t s based on c e r e a l s  (1967a)  considered that  (wheat, b a r l e y and o a t s )  lysine i s  the f i r s t l i m i t i n g amino a c i d , f o l l o w e d by t h r e o n i n e , t r y p t o p h a n and nine.  T h r e o n i n e was  experiment.  methio-  t h e second l i m i t i n g amino a c i d i n b a r l e y i n the p r e s e n t  T h i s s u p p o r t s the f i n d i n g s of p r e v i o u s i n v e s t i g a t i o n s w i t h  b a r l e y and o t h e r c e r e a l s  (Sure, 1955; Pond e_t a l . ,  1958; Rosenberg e t a l . ,  I n the p r e s e n t e x p e r i m e n t , t r y p t o p h a n was  s u f f i c i e n t i n the b a s a l  1959) .  b a r l e y d i e t a c c o r d i n g to finishing pigs.  N.A.S.-N.R.C. (1968) F e e d i n g Standards f o r g r o w i n g -  C o n s e q u e n t l y , i t was n o t i n v e s t i g a t e d .  A l t h o u g h t o t a l s u l f u r amino a c i d ( m e t h i o n i n e + c y s t i n e ) ments of growing p i g a r e w i d e l y a c c e p t e d as b e i n g (N.A.S.-N.R..C., 1968; A.R.C., 1967),  0.5-0.6%  require-  of the d i e t  many r e s e a r c h e r s o v e r r e c e n t y e a r s  have i n d i c a t e d t h a t t h e r e q u i r e m e n t s o f s u l f u r amino a c i d o f p i g s may overestimated.  Beames and Pepper (1969)  adequate f o r o p t i m a l growth. w i t h supplementation of containing  0.27%  i n d i c a t e d that  Chung and Beames (1974)  0.10%  - 0.42%  o b t a i n e d no  is  response  m e t h i o n i n e to an a l l b a r l e y - a m i n o a c i d  methionine + c y s t i n e .  S i m i l a r e v i d e n c e was  many o t h e r r e s e a r c h e r s such as Oestemer ort a l . (1970), and Brown e_t aL. (1974)  0.3  be  r e p o r t e d by  Jensen e t a l . (1965)  s t r o n g l y s u p p o r t i n g the c o n t e n t i o n t h a t the t o t a l  s u l f u r amino a c i d r e q u i r e m e n t s o f growing and f i n i s h i n g p i g s s h o u l d be than  N.A.S.-N.R.C. (1968)  and  f a i l u r e i n r e s p o n s e when a d d i n g acid diet containing  diet  0.44%  A.R.C. (1967) 0.10%  recommended l e v e l s .  m e t h i o n i n e t o an a l l  lower  The  barley-amino  m e t h i o n i n e + c y s t i n e i n the p r e s e n t e x p e r i m e n t  -  60  -  f u r t h e r c o n f i r m e d t h a t m e t h i o n i n e i s not l i m i t i n g i n b a r l e y f o r growing pigs.  T h i s i s i n agreement w i t h  R e r a t and Henry  (1969)  and  of S o l d e v i l a and Meade  Chung and Beames  I t has been r e p o r t e d with l y s i n e , threonine,  results  (1964),  (1974).  t h a t f e e d i n g c e r e a l m i x t u r e s supplemented  tryptophan,  m e t h i o n i n e and  i n some e x p e r i m e n t s  a l s o i s o l e u c i n e , r e s u l t e d i n p e r f o r m a n c e e q u a l to t h a t o b t a i n e d w i t h d i e t s containing p r o t e i n concentrate et.  (Robinson and L e w i s , 1963  grain  ; Miiller  a l . , 1967b) .  The  s i m p l i f i e d d i e t of amino a c i d s added t o s i n g l e c e r e a l d i e t s  (wheat, b a r l e y or corn) used by M i i l l e r and Malek  (1967a, b, c) i n d i c a t e d  t h a t t h i s k i n d o f d i e t c o u l d be employed t o r a i s e p i g s from (approximately  20 Kg l i v e w e i g h t ) .  weaning  Many r e p o r t s have i n d i c a t e d t h a t the  mance of a n i m a l s fed a d i e t w i t h a s i n g l e c e r e a l p l u s amino a c i d s d i e t  perf fail  t o produce p e r f o r m a n c e as good as t h a t a c h i e v e d w i t h n a t u r a l p r o t e i n concentrate  supplemented d i e t  (Chung and Beames, 1974).  Beames and Pepper (1969) a l s o r e p o r t e d e i t h e r w i t h o r w i t h o u t m e t h i o n i n e , was r e p l a c e m e n t o f h a l f soybean c o n c e n t r a t e 45 Kg body w e i g h t .  t h a t the use of  not c o m p l e t e l y  s u c c e s s f u l as  a  t o sorghum d i e t f o r p i g s l e s s t h a n  However, no d i f f e r e n c e i n performance was  p i g s g r o w i n g from 45 Kg to 90 Kg  lysine,  observed i n  between the amino a c i d r e p l a c e d d i e t o r  the o r i g i n a l soybean-sorghum d i e t .  Results  from the p r e s e n t e x p e r i m e n t i n d i c a t e d t h a t d i e t s composed  o f a s i n g l e c e r e a l supplemented w i t h the r e q u i r e d amino a c i d s c o u l d  induce  - 61 -  h i g h p i g p e r f o r m a n c e as good as c o n v e n t i o n a l p r o t e i n c o n c e n t r a t e diets.  Pigs fed w i t h  0.444%  lysine-RCl  and  0.10%  supplemented  t h r e o n i n e added t o  b a r l e y i n a d i e t c o n t a i n i n g adequate m i n e r a l s and v i t a m i n s were n o t c a n t l y i n f e r i o r t o those on the b a r l e y - s o y b e a n  meal d i e t .  signifi-  However, when  the crude p r o t e i n , l y s i n e and t h r e o n i n e l e v e l s i n these two d i e t s i s compared, the b a r l e y - a m i n o vs  17.6%),  a similar lysine level  nine l e v e l  (0.46%  N.R.C. (1968) diet for  a c i d d i e t i s seen to c o n t a i n l e s s c r u d e p r o t e i n  and  vs  0.57%).  The  A.R.C. (1967)  20 t o 45 Kg  pigs.  The  (0.75%  vs  0.75%)  (11.4%  and a l o w e r  threo-  t h r e o n i n e l e v e l s recommended by N.A.S.-  are  0.45%  and  0.45  - 0.50%  d i e t a r y t h r e o n i n e l e v e l of  of  the  0.47%  threo-  n i n e i s the b e s t d i e t of the p r e s e n t e x p e r i m e n t w h i c h agrees w i t h  these  recommendations.  protein  diet, Kg  0.48%  Henry and R£rat (1970)  d i e t a r y t h r e o n i n e was  female p i g s .  The  a d d i t i o n a l methionine 0.1%  r e p o r t e d t h a t on a  the o p t i m a l l e v e l f o r growth o f  s l i g h t l y depressed T h i s may  growth below t h a t o b t a i n e d w i t h  i n d i c a t e t h a t the a d d i t i o n o f  e x t r a L - t h r e o n i n e c r e a t e d a s l i g h t s t r e s s or an amino a c i d Methionine  a d d i t i o n to  0.15%  0.05%  'imbalance'  in  t h r e o n i n e d i e t tended t o improve  performance s l i g h t l y , p o s s i b l y as a r e s u l t o f r e d u c i n g the  Although  20-50  f u r t h e r i n c r e a s e of t h r e o n i n e l e v e l w i t h o r w i t h o u t  threonine a d d i t i o n .  the d i e t .  10%  the d i e t c o n t a i n i n g 0.10%  imbalance.  added t h r e o n i n e was  not  statis-  t i c a l l y i n f e r i o r t o the b a r l e y soybean meal d i e t by u s i n g Tukey's t e s t , i t appeared t h a t the c o n t r o l s o y b e a n - b a r l e y performance.  d i e t s t i l l gave s l i g h t l y b e t t e r  I t i s p o s s i b l e t h a t r e s p o n s e t o the a d d i t i o n o f l y s i n e  t h r e o n i n e t o the b a r l e y was  and  l i m i t e d by o t h e r f a c t o r s s u c h as the l e v e l  t o t a l n i t r o g e n i n the d i e t , a l o w e r b i o l o g i c a l a v a i l a b i l i t y o f l y s i n e  of and  - 62 -  t h r e o n i n e o r o t h e r e s s e n t i a l amino a c i d s , o r t h a t t h e amino a c i d p a t t e r n i n t h e a l l b a r l e y - a m i n o a c i d d i e t was n o t as w e l l b a l a n c e d soybean-barley d i e t although  as i n t h e  the r e q u i r e m e n t s o f a l l e s s e n t i a l amino a c i d s  appeared t o have been met.  The  s o y b e a n - b a r l e y d i e t was s i g n i f i c a n t l y b e t t e r than t h e d i e t  containing higher threonine  (0.15%)  additions w i t h or without methionine i n  the p r e s e n t e x p e r i m e n t . This i s p o s s i b l y as a r e s u l t o f a g r e a t e r i m b a l a n c e . I t i s p o s s i b l e t h a t b e t t e r growth may have been o b t a i n e d w i t h an i n c r e a s e d l y s i n e l e v e l i n the higher threonine d i e t .  The r e s u l t s o f H a r p e r  (1964)  o b t a i n e d w i t h r a t s i n d i c a t e d t h a t an excess o f a p a r t i c u l a r amino a c i d o r o f an i m b a l a n c e d p r o t e i n r e q u i r e d f u r t h e r a d d i t i o n o f the p r i m a r y - l i m i t i n g amino a c i d .  Bayley  and Summers (1968)  p r a c t i c a l corn-soybean d i e t 0.05%  reported that the supplementation  ( 1 4 % crude p r o t e i n )  with  0.1%  of  l y s i n e or  m e t h i o n i n e d i d n o t g i v e a b e n e f i c i a l e f f e c t t o growth and f e e d  efficiency.  However, t h e r e was a p o s i t i v e e f f e c t i f t h e same l e v e l o f  b o t h amino a c i d s were supplemented t o g e t h e r p a r t i c u l a r l y on t h e lower protein diet  (12% crude p r o t e i n ) .  Although  the p i g does n o t r e q u i r e crude p r o t e i n p e r s e . t h e crude  p r o t e i n l e v e l appears t o a f f e c t p e r f o r m a n c e t o some e x t e n t . R e r a t and Henry (1963) i n d i c a t e d t h a t the performance o f p i g s r e c e i v i n g a low l y s i n e d i e t  could  be improved by r a i s i n g t h e n i t r o g e n l e v e l o r by a d d i n g l y s i n e t o t h e d i e t . The. h i g h n i t r o g e n l e v e l o f t h e s o y b e a n - b a r l e y may have c o n t r i b u t e d t o the good p e r f o r m a n c e on t h i s d i e t .  B l a i r e t a l . (1969a) r e p o r t e d t h a t l i v e w e i g h t  -  -  63  g a i n was n o t improved s i g n i f i c a n t l y by i n c r e a s i n g the p r o t e i n l e v e l above 16, 14  and  12% f o r the 23-45,  45-68 and  68-90 Kg  r i e s , r e s p e c t i v e l y . However, feed c o n v e r s i o n s i g n i f i c a n t l y o v e r the 18%.  23-45 Kg  body w e i g h t c a t e g o -  e f f i c i e n c y was  improved  w e i g h t range by i n c r e a s i n g the l e v e l t o  L i v e w e i g h t g a i n was not improved s i g n i f i c a n t l y by i n c r e a s i n g the  l y s i n e l e v e l above 68-90 Kg  1.04,  ranges, r e s p e c t i v e l y .  s i g n i f i c a n t l y during 1.22%.  0.74  the  and  0.70  f o r the  23-45, 45-68  and  Feed e f f i c i e n c y was, however, improved  23-45 Kg  s t a g e by i n c r e a s i n g l y s i n e l e v e l s t o  I t appears t h a t the p r o t e i n l e v e l (about 11%) and l y s i n e l e v e l i n the  b a r l e y - a m i n o a c i d d i e t s of the p r e s e n t experiment may have been the f a c t o r s l i m i t i n g t h e growth and feed e f f i c i e n c y performances o f p i g s d u r i n g t h e e a r l y s t a g e of growth. only  from  T h i s was r e v e a l e d by the growth r a t e d i f f e r e n c e s  20 t o 45 Kg body w e i g h t between  and the c o n t r o l d i e t . r a i s i n g the  nitrogen  0.10%  threonine  occuring  or over d i e t s  I t i s p o s s i b l e t h a t the growth r a t e can be improved by l e v e l of the d i e t s t h r o u g h amino a c i d a d d i t i o n  t h a t p e r i o d . The l y s i n e l e v e l a p p a r e n t l y  during  was s u f f i c i e n t b u t not the n i t r o g e n  l e v e l when compared t o the r e p o r t s o f B l a i r e_t _ a l . (1969a) . I n the p r e s e n t e x p e r i m e n t , the growth r a t e d i f f e r e n c e o c c u r e d body w e i g h t between the c o n t r o l d i e t and the  o n l y from 0.10%  20 t o 45 Kg  threonine  supplemented  diet.  Chung and Beames (1974) gilts 0.9%  b u t n o t w i t h barrows  showed s i g n i f i c a n t growth improvement w i t h  by i n c r e a s i n g the l y s i n e l e v e l from  of the a l l b a r l e y d i e t c o n t a i n i n g  about  0.75%  10% crude p r o t e i n .  However,  i t i s d i f f i c u l t t o e x p l a i n the s i g n i f i c a n t I n c r e a s e i n d a i l y w e i g h t  gain  obtained  0.75%  by a d d i n g  0.05%  threonine  t o the b a r l e y d i e t c o n t a i n i n g  to  - 64 -  l y s i n e when f e d t o g i l t s ;  a s i g n i f i c a n t i n c r e a s e c o u l d a l s o be o b t a i n e d by  f u r t h e r i n c r e a s i n g the l y s i n e l e v e l to  0.90%.  The response  to other  l i m i t i n g amino a c i d s o b t a i n e d when t h e f i r s t l i m i t i n g amino a c i d i s n o t a t an o p t i m a l l e v e l i s c o n t r a r y t o t h e g e n e r a l t h e o r y o f a s t e p w i s e as i l l u s t r a t e d by t h e c o n t o u r maps o f Rosenberg e t a l . (1959); where s e v e r a l amino a c i d s a r e e q u a l l y l i m i t i n g , a response when a l l a r e s u p p l i e d t o g e t h e r ( F i s h e r , 1965). that  0.75%  of the p i g .  Chung and Beames (1974) in  although  i s obtained only  I t i s therefore  l y s i n e i n t h e d i e t i s adequate f o r t h e growing The i n c r e a s e d growth response  response,  apparent  and f i n i s h i n g  and f e e d e f f i c i e n c y o b t a i n e d by  i n d i c a t e d t h a t t h r e o n i n e was a l i m i t i n g amino a c i d  these a l l b a r l e y d i e t s .  The l i m i t i n g f a c t o r o f t h r e o n i n e may have been  one o f t h e main f a c t o r s w h i c h r e s u l t e d i n a f a i l u r e t o show t h e response o f i n c r e a s i n g l y s i n e from observed  0.75%  to  0.90%  by M o r r i s o n e t a l . (1961)  that l y s i n e supplementation threonine concentration.  and  o f the d i e t .  Braude e t a l . (1972)  perhap  levels  indicated  r e s u l t s i n a p r o g r e s s i v e decrease i n plasma  The h i g h l e v e l o f l y s i n e c o u l d b e more  i n t h e e a r l y s t a g e than i n l a t e r s t a g e s o f growth. that  The e v i d e n c e  h i g h e r than  0.75%  s i n g t h r e o n i n e l e v e l s commencing a t  imbalanced  I t i s therefore  suggested  lysine with progressively increa-  0.47%  i n a l l barley-amino  acid  diets  s h o u l d be f u r t h e r i n v e s t i g a t e d t o see i f a d d i t i o n a l improvements i n p i g performance c o u l d b e a c h i e v e d .  The e v i d e n c e based on p i g growth and f e e d e f f i c i e n c y i n t h e p r e s e n t experiment 0.47% for  suggested  t h a t t h r e o n i n e i s adequate f o r o p t i m a l growth a t  o f the l o w - p r o t e i n barley-amino the g r o w i n g - f i n i s h i n g p i g .  acid diet containing  0.75%  lysine  - 65 -  D r e s s i n g p e r c e n t a g e d i d n o t d i f f e r s i g n i f i c a n t l y between t r e a t ments and s e x . (1972)  J u r g e r (1967), Meade et al_. (1969) and P i e r c e and Bowland  o b t a i n e d no e f f e c t on d r e s s i n g p e r c e n t a g e from v a r y i n g d i e t a r y  p r o t e i n l e v e l s , thus s u p p o r t i n g the r e s u l t s of the p r e s e n t showing the h i g h p r o t e i n c o n t r o l d i e t (about  17.6%  experiment  crude p r o t e i n )  to  produce a d r e s s i n g p e r c e n t a g e s i m i l a r to t h a t o b t a i n e d w i t h t h e low p r o t e i n treatment  (about  11% crude p r o t e i n ) .  Many r e p o r t s i n t h e l i t e r a t u r e have shown l y s i n e o f low p r o t e i n c e r e a l to markedly a l . , 1959; Bowland, 1962; e t a l . , 1972).  improve  supplementation  carcass lean content  (Brooks e t  C a h i l l y e t a l . , 1963; N i e l s e n e t a l . , 1963;  Braude  However, v e r y l i t t l e i n f o r m a t i o n has been p r e s e n t e d on  the  e f f e c t o f t h r e o n i n e a d d i t i o n t o a l o w - p r o t e i n c e r e a l w i t h adequate l y s i n e s u p p l e m e n t a t i o n on c a r c a s s l e a n c o n t e n t . i n d i c a t e d a gradual decrease  The d a t a i n the p r e s e n t s t u d y  (not s i g n i f i c a n t at  P < 0.05)" i n " b a c k f a t  t h i c k n e s s c o r r e s p o n d i n g to i n c r e a s e d l e v e l o f t h r e o n i n e However, the t h i c k n e s s of b a c k f a t CP < 0.05)  reduced- o n l y a t  0.15%  40 mm  supplement.  from m i d - l i n e was  significantly  l e v e l of threonine supplementation.  T h i s suggests t h a t to a c h i e v e a s i g n i f i c a n t improvement i n c a r c a s s q u a l i t y , h i g h e r l e v e l o f t h r e o n i n e s u p p l e m e n t a t i o n may be r e q u i r e d . Beames of  (1974)  0.05%  backfat  were a l s o u n a b l e to show any d i f f e r e n c e from the a d d i t i o n  threonine to a b a r l e y - l y s i n e d i e t  Higher  Chung and  threonine additions  in  Treatments  f i g u r e s not s i g n i f i c a n t l y d i f f e r e n t  the b a r l e y - s o y b e a n c o n t r o l d i e t .  (0.75%  Similarly,  lysine).  5  and  6  gave  from v a l u e s o b t a i n e d on Treatments  4  and  5  - 66 -  were s t a t i s t i c a l l y as good as t h e c o n t r o l d i e t i n r e s p e c t t o b a c k f a t from t h e m i d - l i n e .  I n g e n e r a l , the r e s u l t s i n d i c a t e that the a d d i t i o n of  t h r e o n i n e t o the b a r l e y - a m i n o a c i d the b a c k f a t  40 mm  and improve  (0.75% l y s i n e )  carcass q u a l i t y .  also i n f l u e n c e carcass fatness.  d i e t tends t o d e c r e a s e  V a r i a t i o n i n f e e d i n t a k e can  However, as t h e r e were n o t s i g n i f i c a n t  d i f f e r e n c e s between t r e a t m e n t s i n mean d a i l y f e e d i n t a k e t h i s would n o t have been a c o n t r i b u t o r y  factor.  Eye muscle i n d e x and eye muscle a r e a were n o t a f f e c t e d c a n t l y o v e r t h e 0.05%  to  0.15%  signifi-  range o f t h r e o n i n e a d d i t i o n a l t h o u g h  t h e l e v e l o f t h r e o n i n e s u p p l e m e n t a t i o n was t h e o n l y l e v e l on w h i c h t h e eye muscle i n d e x d i d n o t d i f f e r s i g n i f i c a n t l y from t h a t o b t a i n e d c n t h e b a r l e y soybean meal c o n t r o l d i e t .  The o v e r a l l r e s u l t s o f t h e p r e s e n t experiment  showed t h a t t h e  l o w e s t back f a t t h i c k n e s s , l a r g e s t eye muscle a r e a and eye muscle i n d e x was o b t a i n e d from t h e b a r l e y - s o y b e a n c o n t r o l d i e t , n i n e supplemented  a l t h o u g h some o f t h e t h r e o -  d i e t s gave v a l u e s w h i c h were n o t s t a t i s t i c a l l y l o w e r  than  the c o n t r o l .  Many r e p o r t s have i n d i c a t e d t h a t l o w e r i n g t h e crude p r o t e i n below about  16 - 17%,  a t l e a s t i n t h e e a r l y s t a g e s o f t h e growing p e r i o d ,  w i l l p r o d u c e adverse e f f e c t s on c a r c a s s q u a l i t y Bowland et a l . , 1959  level  and  The i n f e r i o r i t y o f c a r c a s s  ( A s h t o n e t a l . , 1955;  A.R.C., 1967; Tjong-A-Hung e t a l . , q u a l i t y on  1972).  the present barley-amino  acid  - 67 -  diets  (about  11% crude p r o t e i n )  the b a r l e y - s o y b e a n c o n t r o l  (17.5  compared w i t h the c a r c a s s e s from p i g s on crude p r o t e i n )  d i e t may be due t o  i n a d e q u a t e n i t r o g e n c o n t e n t s i n the former d i e t s f o r o p t i m a l body p r o t e i n synthesis.  C o n f l i c t i n g r e p o r t s by Clawson.(1967), and Bowland (1972)  Meade (1966b) and P i e r c e  i n d i c a t e no i n f l u e n c e of d i e t a r y p r o t e i n on l o i n  and back f a t . t h i c k n e s s .  However, i t appeared  d i e t s used by above a u t h o r s were over  area  that the p r o t e i n l e v e l i n  14% crude p r o t e i n  d e s i g n e d t o c r i t i c a l l y t e s t the e f f e c t o f p r o t e i n  and t h e r e f o r e n o t  levels.  H i g h e r mean d a i l y g a i n s were observed i n t h e b a r r o w than t h e g i l t w h i c h was i n agreement w i t h t h e r e s u l t s o f Tjong-A-Hung e_t a l . (1972)  and  Chung and Beames ( 1 9 7 4 ) . However i t i s i n disagreement w i t h the f i n d i n g s o f N e w e l l and Bowland (1972)  and  P i e r c e and Bowland (1972).  G i l t s were s u p e r i o r t o b a r r o w s i n a l l c a r c a s s measurements. r e s u l t i s s u p p o r t e d by many p r e v i o u s i n v e s t i g a t o r s  This  ( e . g . Wong e t a l . , 1968;  Young e t a l . , 1968; N e w e l l and Bowland, 1972 ; Tjong-A-Hung e t a l . , 1972; Lodge e_t a l . , 1972b; Chung and Beames, 1974).  There was no i n t e r a c t i o n between d i e t and s e x i n t h e p r e s e n t experiment.  Chung and Beames (1974)  i n t e r a c t i o n between d i e t and s e x .  i n a s i m i l a r experiment  I t appears  observed  t h a t d i e t and sex i n t e r a c t i o n  has been i n c o n s i s t e n t l y found i n s e v e r a l p r e v i o u s i n v e s t i g a t i o n s .  - 68  D.  I t may  be c o n c l u d e d  -  CONCLUSION  t h a t t h r e o n i n e was  the second l i m i t i n g amino  a c i d i n b a r l e y as used i n t h i s e x p e r i m e n t f o r the f i n i s h i n g p i g and b a r l e y can be used as the s o l e p r o t e i n s o u r c e t h a t the p r o p e r l e v e l s o f l y s i n e and With  0.75%  t h r e o n i n e a r e added.  (0.47%  t o t a l threonine)  g a i n and f e e d c o n v e r s i o n e f f i c i e n c y . and  0.05%  for f i n i s h i n g pigs providing  l y s i n e i n the a l l b a r l e y d i e t , a  a d d i t i o n t o the d i e t  threonine plus  0.10%  improvement i n p i g p e r f o r m a n c e .  that  0.10%  L-threonine  produced the b e s t mean d a i l y  F u r t h e r a d d i t i o n of  0.05%  L-threonine  DL-methionine d i d n o t g i v e any a d d i t i o n a l The b a r l e y - l y s i n e d i e t c o n t a i n i n g  0.75%  t o t a l l y s i n e gave the p o o r e s t p e r f o r m a n c e i n b o t h r a t e o f growth and conversion e f f i c i e n c y . plus  0.10%  The  0.10%, 0.15%  t h r e o n i n e and  m e t h i o n i n e improved the mean d a i l y g a i n by  threonine  22.1%,  and  r e s p e c t i v e l y and  12.8%  r e s p e c t i v e l y when they were added to a b a r l e y - l y s i n e d i e t c o n t a i n i n g  0.75%  total lysine.  0.10% the  to  (17.6% crude p r o t e i n )  45 Kg  12.9%  and  D i f f e r e n c e s i n the r a t e o f growth on the b a r l e y -  or more added t h r e o n i n e 20  15.5%,  13.0%  14.7%  soybean d i e t  f e e d c o n v e r s i o n e f f i c i e n c y by  0.15%  feed  and b a r l e y amino a c i d d i e t s c o n t a i n i n g  (about  body w e i g h t p e r i o d .  11% crude p r o t e i n )  occured  The e s s e n t i a l amino a c i d  of the h i g h e r b a r l e y - l y s i n e d i e t s c o n t a i n i n g  0.10%  only at content  o r more t h r e o n i n e  s u f f i c i e n t t o meet the r e q u i r e m e n t s o f the g r o w i n g p i g a c c o r d i n g to N.A.S,-N,R,C, (1968)  feeding standards.  of the amino a c i d supplemented d i e t s may  are  the  However the t o t a l n i t r o g e n  content  have been i n s u f f i c i e n t d u r i n g  the  -  growing  (prior to  69  45 Kg body weight)  -  period of growth.  I t i s possible  that growth rate could have been improved by increasing the nitrogen l e v e l of d i e t during this period. The barley-soybean addition of graded levels of  meal diet gave the best carcass q u a l i t y . L-threonine  The  to the b a r l e y - l y s i n e diet  improved carcass q u a l i t y . G i l t s grew more slowly and produced leaner carcasses than barrows.  -  IV.  A.  a.  70  -  PIG EXPERIMENT I I  EXPERIMENTAL PROCEDURE  General In feeding experiments,  r a t e and  growth, p e r f o r m a n c e as a s s e s s e d  Although  a r e f e d ad  libitum.  c a r c a s s measurements a r e r e a s o n a b l y w e l l c o r r e l a t e d w i t h l e a n and  t o t a l c a r c a s s n i t r o g e n t h e s e g i v e no i n d i c a t i o n o f the causes  o f v a r i a t i o n s between t r e a t m e n t s accepted  that nitrogen balance  ing protein quality. designed  i n nitrogen storage.  techniques  Therefore,  I t i s generally  a r e much more v a l u a b l e i n a s s e s s -  the n i t r o g e n m e t a b o l i s m e x p e r i m e n t  was  t o d e t e r m i n e the causes o f v a r i a t i o n s i n n i t r o g e n r e t e n t i o n i n  t i s s u e s of p i g s r e c e i v i n g  b.  growth  feed e f f i c i e n c y g i v e s no i n d i c a t i o n s of the v a r i a t i o n i n n i t r o g e n  r e t e n t i o n i n the t i s s u e s , p a r t i c u l a r l y when the animals  content  by  the d i e t s used i n E x p e r i m e n t I .  Animals A t o t a l of  w e i g h i n g between  18 male c a s t r a t e Y o r k s h i r e - L a n d r a c e  39 and 51 Kg were a s s i g n e d  crossbred  to t h r e e groups.  pigs  Each group  c o n s i s t e d o f s i x a n i m a l s w h i c h were p l a c e d i n s i x m e t a b o l i s m c r a t e s f o r a three-week p e r i o d . randomly.  The  W i t h i n groups s i x e x p e r i m e n t a l  f i r s t week was  d i e t s were a s s i g n e d  an a c c l i m a t i z a t i o n p e r i o d .  The second  t h i r d weeks were d i v i d e d i n t o two one-week c o l l e c t i o n p e r i o d s .  and  - 71 -  c.  Diets D i e t s were t h e same as those used i n P i g E x p e r i m e n t I .  was p r e p a r e d by p a s s i n g t h e b a r l e y through o f a hammer m i l l .  Each d i e t  t h e f i n e s c r e e n (7 mm d i a m e t e r )  Feed samples were t a k e n f o r m o i s t u r e and n i t r o g e n  determination a t the s t a r t of the t r i a l .  d.  Management (i)  Housing The m e t a b o l i s m room was m a i n t a i n e d  a t a temperature o f  21° C  w i t h t h e r m o s t a t i c a l l y - c o n t r o l l e d space h e a t e r s . The m e t a b o l i s m c r a t e s were a m o d i f i c a t i o n o f the S h i n f i e l d (Frape e_t a l . , 1968) .  design  The f i b r e g l a s s u r i n e t r a y was i n c l i n e d from f r o n t  to r e a r a t an a n g l e o f a p p r o x i m a t e l y  30°  from t h e h o r i z o n t a l .  A fine wire  s c r e e n was p l a c e d on the u r i n e t r a y i n o r d e r t o r e t a i n t h e s m a l l amount o f f e c e s f a l l i n g beyond t h e f e c e s t r a y w h i c h was l o c a t e d a t t h e r e a r o f t h e f l o o r as shown i n F i g u r e 1 .  Each p i g had a t t a c h e d a canvas b e l t t o w h i c h was a t t a c h e d a p i e c e o f rubber  tubing.  The canvas b e l t was s t u c k w i t h cement around t h e abdomen  o f t h e p i g w i t h t h e rubber  tube h a n g i n g j u s t i n f r o n t o f t h e p e n i s .  The  purpose o f t h i s d e s i g n was t o l e a d the u r i n e down t o t h e u r i n e t r a y and t o minimize  (ii)  p o s s i b l e u r i n e l o s s from s p r a y i n g d u r i n g u r i n a t i o n ( F i g u r e 2 ) .  Feeding  method  P i g s were f e d t w i c e d a i l y ad l i b i t u m a t  9:00 a.m.  and  1:00  p.m.  - 72 -  F i g u r e 2. P i g i n the m o d i f i e d a d j u s t a b l e cage, h e l d w i t h b e l t and r u b b e r t u b i n g to m i n i m i z e u r i n e l o s s  canvas  - 73 -  for  40 m i n u t e s p e r f e e d .  The  d i e t was  by w e i g h t j u s t b e f o r e f e e d i n g . minute  mixed w i t h e q u a l amounts of w a t e r  Water was  p e r i o d a f t e r each f e e d i n g .  provided  ad l i b i t u m f o r a  P r i o r to the p r o v i s i o n of w a t e r ,  r e s i d u e s were removed, p l a c e d i n p l a s t i c bags and s t o r e d a t end of each one-week c o l l e c t i o n p e r i o d , the r e s i d u e s and  dried  at  60°  C  e.  Feces and U r i n e C o l l e c t i o n  3° C.  20 feed At  f o r each p i g were  to constant weight (approximately  72  the pooled  hours).  A l l f e c e s were c o l l e c t e d d a i l y i n p l a s t i c bags and s t o r e d a t u n t i l completion p i g was ximately 1971) .  of the seven-day t r i a l .  then pooled 500  g  and weighed and  was  U r i n e was  d r i e d at  (50%  collection period.  f.  V/V)  an a c c u r a t e l y weighed a l i q u o t of a p p r o C  for  72 h o u r s  each day  measured each day  p l a s t i c j a r and s t o r e d a t  nitrogen  t o t a l f e c a l o u t p u t of each  (Saben and  c o l l e c t e d i n a p l a s t i c j a r t o w h i c h was .added  diluted sulphuric acid U r i n e volume was  60°  The  The  3° C  3°  and a  10%  Bowland, 50 ml  of...  t o a v o i d l o s s of n i t r o g e n . aliquot collected into a  f o r p o o l i n g a t the end o f each one-week  sample of p o o l e d u r i n e was  used s u b s e q u e n t l y f o r  determination.  S t a t i s t i c a l A n a l y s i s of Data The  of v a r i a n c e  a n a l y s e s were done as f o r a one-way c l a s s i f i c a t i o n a n a l y s i s  ( d i e t as t r e a t m e n t )  for nitrogen balance,  w i t h or without  a covariable.  The  data  apparent n i t r o g e n d i g e s t i b i l i t y , n i t r o g e n absorbed  as a p e r c e n t a g e of n i t r o g e n i n t a k e , n i t r o g e n r e t a i n e d as a p e r c e n t a g e o f n i t r o g e n absorbed and d r y m a t t e r d i g e s t i b i l i t y were s u b j e c t e d  to  an  C  - 74 -  a n a l y s i s of variance  (UBC-MFAV, Halm and L e , 1974) and t h e means from  comparison s h o w i n g s i g n i f i c a n t Test (1953). analysis  F  v a l u e s were t e s t e d a c c o r d i n g t o Tukey's  N i t r o g e n b a l a n c e d a t a were a l s o a n a l y z e d by c o v a r i a n c e  UBC-MFAV  (Halm and L e , 1974) w i t h f e e d i n t a k e and n i t r o g e n  i n t a k e as c o v a r i a b l e s .  - 75 -  B.  RESULTS .  The summarized r e s u l t s o f the p i g m e t a b o l i s m s t u d i e s a r e shown i n Table 7  .  With equal l e v e l s of l y s i n e  (0.75%)  i n the d i e t , the s u p p l e -  m e n t a t i o n o f L - t h r e o n i n e t o the b a r l e y - a m i n o a c i d d i e t improved balance  significantly.  The n i t r o g e n b a l a n c e improved p r o g r e s s i v e l y b u t  n o t s i g n i f i c a n t l y from response was nine d i e t .  the n i t r o g e n  0.05  to  0.15%  threonine addition.  No  further  o b t a i n e d from m e t h i o n i n e s u p p l e m e n t a t i o n o f the h i g h e s t t h r e o The n i t r o g e n b a l a n c e f i g u r e s o f the b a r l e y - a m i n o a c i d d i e t s were  s i g n i f i c a n t l y i n f e r i o r t o t h o s e of t h e b a r l e y - s o y b e a n c o n t r o l d i e t e x c e p t for  the  0.15%  t h r e o n i n e supplemented  c a n t l y from the c o n t r o l .  d i e t which d i d not d i f f e r  When n i t r o g e n b a l a n c e was  signifi-  adjusted f o r feed  i n t a k e , c o m p a r a t i v e r e s u l t s were s i m i l a r to those w i t h o u t f e e d i n t a k e a d j u s t e d e x c e p t t h a t the n o n - t h r e o n i n e supplemented c a n t l y d i f f e r e n t from Treatments b a l a n c e was  t h r e o n i n e supplemented the  and  6.  a d j u s t e d f o r n i t r o g e n i n t a k e the  became t h e b e s t a l t h o u g h i t was  than  3, 4  d i e t became i n s i g n i f i -  However, when n i t r o g e n 0.15%  t h r e o n i n e added d i e t  i n s i g n i f i c a n t l y d i f f e r e n t from a l l o t h e r  and c o n t r o l d i e t .  n o n - t h r e o n i n e supplemented  However, i t was  diet.  Moreover,  significantly  better  the d i e t w i t h o u t  t h r e o n i n e added d i d n o t d i f f e r s i g n i f i c a n t l y from Treatments  1, 3, 4  and  6.  N i t r o g e n absorbed as a p e r c e n t a g e o f n i t r o g e n i n t a k e showed no s i g n i f i c a n t d i f f e r e n c e s between amino a c i d supplemented o n l y and l y s i n e p l u s lower  0.05%  t h r e o n i n e supplemented  v a l u e s than t h a t o f c o n t r o l .  d i e t s b u t the l y s i n e  d i e t s gave s i g n i f i c a n t l y  Hie c o n t r o l d i e t gave a s i g n i f i c a n t l y  l o w e r n i t r o g e n r e t e n t i o n as a p e r c e n t a g e of n i t r o g e n i n t a k e than a l l b a r l e y -  - 76 -  amino acid d i e t s .  The diets with added threonine did not d i f f e r  signifi-  cantly from each other but tended to improve from the low to the higher levels of threonine addition.  The p i c t u r e f o r nitrogen retained as a per-  centage of nitrogen absorbed was s i m i l a r to that obtained when nitrogen retention was expressed  as a percentage of nitrogen intake.  Dry matter d i g e s t i b i l i t y showed no s i g n i f i c a n t differences between diets.  However, nitrogen intake and nitrogen d i g e s t i b i l i t y were s i g n i f i -  cantly higher i n the barley-soybean  control treatment but there were no  s i g n i f i c a n t differences among the barley-amino acid supplemented d i e t s . In summary, the results showed that the barley diet with lysine-HCl  0.444%  addition only was s t i l l l i m i t i n g i n threonine values f o r n i t r o -  gen balance. Nitrogen absorbed as percentage of nitrogen intake, nitrogen retained as percentage of nitrogen intake and nitrogen retained as percentage of nitrogen absorbed were generally improved by threonine supplementation.  - 77 -  Table 7 .  Summary o f t h e e f f e c t s o f s u p p l e m e n t a t i o n  of  b a r l e y w i t h amino a c i d s on apparent d r y m a t t e r d i g e s t i b i l i t y , n i t r o g e n balance, apparent n i t r o g e n d i g e s t i b i l i t y and on v a r i o u s n i t r o g e n r e t e n t i o n indices  Treatment  1 2 3 4 5 6 _ 0.75%lys B a s a l + B a s a l + B a s a l + B a s a l + (control) ( B a s a l ) 0.05%thr 0.10%thr 0.15%thr 0.15%thr+ 0.10%met.  S o y  T o t a l feed intake(g) Total N intake(g)  Result of s i g n i ficant test**  b a r l e y  13424  11833  12701  12538  12567  12244  ±595  337.60  208.36  230.72  227.88  227.66  78.43  77.76  76.26  77.95  77.61  77.14  ±1.11  142563  N digested  289.80  143.66  152.40  159.37  158.09  154.73  ±7.39  145632  N  balance(g)  133.27  87.78  103.65  107.63  114.48  102.12  ±6.23  154362  N balance^ a d j u s t e d by feed i n t a k e ( g )  128.53  91.67  102.84  107.70  114.40  103.78  ±5.42  154632  N balance § a d j u s t e d by N intake(g)  104.14  97.07  107.83  112.50  119.40  107.98  ±5.72  546312  76.78  69.11  66.15  69.91  69.54  69.77  ±2.41  146523  N retained (%) N intake  35.44  42.07  44.84  47.32  50.52  45.99  ±2.12  546321  N retained N absorbed  46.24  61.18  67.91  67.70  72.26  66.16  ±3.37  534621  D.M. D i g e s t i bility(%)  N absorbed N intake  W o )  Standard e r r o r of treatment  **  223.49 ±11.78  135462  means.  Treatment numbers n o t u n d e r s c o r e d by t h e same l i n e a r e s i g n i f i c a n t l y d i f f e r e n t a t t h e 5% l e v e l o f p r o b a b i l i t y (Tukey, 1953). C o v a r i a b l e f e e d i n t a k e i s s i g n i f i c a n t (P < 0.05). C o v a r i a b l e N i n t a k e i s h i g h l y s i g n i f i c a n t (P < 0.01).  134562  - 78  C.  The to the  -  DISCUSSION  r e s u l t s of the e x p e r i m e n t showed t h a t the a d d i t i o n of  threonine  b a r l e y - l y s i n e d i e t p r o g r e s s i v e l y improved the d i e t a r y p r o t e i n  quality.  There were s l i g h t v a r i a t i o n s f o r n i t r o g e n b a l a n c e ,  absorbed/nitrogen intake, nitrogen retained/nitrogen retained/nitrogen  The  absorbed  0.15%  f o r a l l the t h r e o n i n e  threonine  intake  nitrogen and  nitrogen  supplemented d i e t s .  supplemented d i e t gave the b e s t r e s u l t s b u t  not s i g n i f i c a n t l y so e x c e p t f o r n i t r o g e n a b s o r b e d / n i t r o g e n i n t a k e . 0.15%  threonine  supplemented d i e t a l s o appeared t o be as good as  The (p <  0.05)  the b a r l e y - s o y b e a n c o n t r o l d i e t i n terms of n i t r o g e n b a l a n c e .  An L-lysine-HCl  improvement i n n i t r o g e n b a l a n c e of a n i m a l s by to g r a i n has been r e p o r t e d  E r i c s o n e_t a l . , 1962;  by many i n v e s t i g a t o r s  S o l d e v i l a and Meade, 1964;  P i c k and Meade,1971; Braude e t a l . , 1 9 7 2 ) .  supplemented d i e t (1974)  (0.45% l y s i n e )  Bowland and  (e.g.  Grimson,  Braude e t a l . (1972) r e p o r t e d  n i t r o g e n r e t a i n e d as p e r c e n t a g e of i n t a k e was l y s i n e supplemented h i g h b a r l e y d i e t  the a d d i t i o n of  s i g n i f i c a n t l y higher  (0.57% l y s i n e )  than  f o r t h e growing p i g .  1969; that  i n the  non-lysine  Chung and Beames  showed no r e s p o n s e to a d d i n g f u r t h e r l y s i n e t o a b a r l e y p l u s l y s i n e  diet containing  0.75%  l i m i t i n g at this  level.  l y s i n e , i n d i c a t i n g some o t h e r amino a c i d to  P i c k and Meade (1971) r e p o r t e d l y s i n e has  significantly  more n i t r o g e n  (p < 0.01)  t h a n those f e d  0.54%  be  that r a t s fed d i e t s containing  greater  gain/feed  lysine diets.  r a t i o and  0.73%  retained  However, i n c r e a s i n g  the  - 79 -  d i e t a r y l y s i n e to  0.92%  d i d not e f f e c t f u r t h e r improvements i n any o f  the  response c r i t e r i a .  Improvement o f n i t r o g e n b a l a n c e by s y n t h e t i c t h r e o n i n e  supplemen-  t a t i o n to a low p r o t e i n d i e t has been s t u d i e d by some r e s e a r c h e r s 1963;  M l i l l e r and Rozman, 1968;  Evans (1963) when  the  diet  nine content 0.58%  was  up to  B r e s s a n i , 1971;  (Evans,  Chung and Beames, 1974) .  r e p o r t e d t h a t maximum n i t r o g e n r e t e n t i o n was  obtained  s u p p l i e d w i t h c r y s t a l l i n e amino a c i d s w i t h the  threo-  0.43%  of the d i e t .  F u r t h e r a d d i t i o n o f t h r e o n i n e up  to  o f the d i e t d i d not improve n i t r o g e n r e t e n t i o n , r a t e o f growth or  feed c o n v e r s i o n e f f i c i e n c y under the m e t a b o l i s m cage c o n d i t i o n s .  Both d i e t s  contained approximately  The  0.70%  lysine  p r e s e n t e x p e r i m e n t showed t h a t w i t h  and  0.75%  0.64%  t o t a l l y s i n e i n the b a s a l d i e t ,  n i t r o g e n r e t e n t i o n improved p r o g r e s s i v e l y up to (0.47%  o f the d i e t ) .  (0.52%  o f the d i e t )  This c l o s e l y supported  improved by  threonine  Evan  (1963).  t h r e o n i n e supplements  improvement was  Chung and Beames (1974)  obtained  obtained  the s i m i l a r  with  by results  They demonstrated t h a t n i t r o g e n r e t e n -  threonine supplementation  of a b a r l e y - l y s i n e d i e t .  The marked r e s p o n s e f o r improvement i n n i t r o g e n r e t e n t i o n by a d d i t i o n confirmed  respect  i n c h i l d r e n above t h a t o b t a i n e d  f u r t h e r nitrogen balance  w i t h b a r l e y d i e t s f o r growing p i g s . t i o n was  0.15%  the r e s u l t s o f  r e p o r t e d t h a t l y s i n e and  to r o l l e d o a t s improved n i t r o g e n b a l a n c e  methionine a d d i t i o n .  threonine a d d i t i o n  d i d not show a s i g n i f i c a n t improvement w i t h  B r e s s a n i (1971)  No  0.10%  The h i g h e r l e v e l a d d i t i o n o f  to n i t r o g e n r e t e n t i o n .  l y s i n e alone.  methionine.  Chung and Beames's r e s u l t .  threonine  - 80 -  M i i l l e r and Rozman (1968) tryptophan,  showed t h a t e i t h e r l y s i n e , t h r e o n i n e  or  and m e t h i o n i n e s u p p l e m e n t a t i o n o f b a r l e y f o r g r o w i n g - f i n i s h i n g  p i g s improved the n i t r o g e n r e t a i n e d / n i t r o g e n d i g e s t e d r a t i o as w e l l as d a i l y g a i n and  feed e f f i c i e n c y .  that l y s i n e , threonine  Chung and Beames (1974)  also indicated  and m e t h i o n i n e s u p p l e m e n t a t i o n of b a r l e y gave an  improvement i n n i t r o g e n b a l a n c e and n i t r o g e n r e t a i n e d / n i t r o g e n i n t a k e . present  The  e x p e r i m e n t gave r e s u l t s w h i c h were i n agreement w i t h those o f  M i i l l e r and Rozman (1968)  and  Chung and Beames (1974) .  However, the  addi-  t i o n of m e t h i o n i n e t o the b a r l e y - l y s i n e - t h r e o n i n e d i e t d i d n o t improve the nitrogen retention, nitrogen retained/nitrogen intake n i t r o g e n absorbed  and  nitrogen retained/  b u t r a t h e r s l i g h t l y d e p r e s s e d the maximum v a l u e s  above c r i t e r i a o b t a i n e d  f o r l y s i n e and  threonine  additions only.  f o r the  This  was  i n agreement w i t h the r e s u l t s r e p o r t e d by some o t h e r i n v e s t i g a t o r s ( S o l d e v i l a and Meade, 1964;  Bowland and Grimson, 1969).  addition depressing i n d i e t may  The  nitrogen balance i s probably  reason f o r methionine t h a t the m e t h i o n i n e  have been adequate f o r the g r o w i n g - p i g and  m e t h i o n i n e may  content  t h a t the a d d i t i o n o f  have c r e a t e d a s l i g h t i m b a l a n c e .  Bowland and Grimson (1969) r e t a i n e d / n i t r o g e n absorbed  v a l u e was  supplemented low p r o t e i n d i e t  i n d i c a t e d that a b e t t e r nitrogen obtained w i t h a  (14% crude p r o t e i n )  lysine-methionine  than w i t h a h i g h e r  pro-  t e i n o r an amino a c i d unsupplemented low p r o t e i n d i e t f o r e a r l y weaned p i g s . D a i l y n i t r o g e n r e t e n t i o n was  i n c r e a s e d when o n l y  of b o t h L - l y s i n e and D L — m e t h i o n i n e , was percent  urea.  The  L-lysine ,  instead  added t o d i e t s c o n t a i n i n g  o b s e r v a t i o n s u g g e s t e d t h a t the m e t h i o n i n e was  second l i m i t i n g amino a c i d a f t e r l y s i n e .  T h i s was  three not  the  a l s o i n agreement w i t h  -  the p r e s e n t  81  -  e x p e r i m e n t w h i c h showed no improvement i n p i g performance w i t h  m e t h i o n i n e a d d i t i o n to the b a r l e y amino a c i d d i e t . g r e a t r e s p o n s e to t h r e o n i n e  On  the o t h e r hand,  i n the a l l b a r l e y d i e t s t r o n g l y s u g g e s t e d t h a t  t h r e o n i n e i s the second l i m i t i n g amino a c i d a f t e r l y s i n e f o r the finishing pig.  the  M o r e o v e r , Chung and Beames (1974)  growing-  demonstrated t h a t  c i n e added to a b a r l e y + l y s i n e . + t h r e o n i n e + m e t h i o n i n e  isoleu-  d i e t d i d not  give  f u r t h e r improvement i n n i t r o g e n - r e t e n t i o n i n d i c a t i n g t h a t i s o l e u c i n e was not l i m i t i n g a t t h i s l e v e l s of i n c l u s i o n  of the o t h e r amino a c i d s i n t h e s e  d i e t s f o r growing p i g s .  The  dry m a t t e r d i g e s t i b i l i t y of b a r l e y - s o y b e a n and  a c i d d i e t s were not s i g n i f i c a n t l y d i f f e r e n t . d i e t gave the l o w e s t  The b a r l e y - s o y b e a n c o n t r o l  figure for nitrogen retained/nitrogen intake  n i t r o g e n r e t a i n e d / n i t r o g e n absorbed, d i e t contained  barley-amino  and  w h i c h would be u n d e r s t a n d a b l e as  a h i g h l e v e l of n o n - e s s e n t i a l amino a c i d s and  thus a h i g h e r  t o t a l n i t r o g e n l e v e l than t h a t r e q u i r e d f o r maximum performance. r e s u l t s of Chung and Beames (1974)  this  The  w i t h p i g s and Bowland and Grimson (1969)  with r a t s support t h i s f i n d i n g .  According  to M e t t a and M i t c h e l l (1956)  and R i p p o n (1959),  the  b i o l o g i c a l v a l u e of d i f f e r e n t p r o t e i n s d e c r e a s e d l i n e a r l y as the p r o t e i n c o n c e n t r a t i o n or i n t a k e i s i n c r e a s e d , 1967) .  B e c k e r e t a l . , 1963,  A.R.C.,  I t i s s u g g e s t e d t h a t the l o w e r a p p a r e n t b i o l o g i c a l v a l u e o f  s o y b e a n - b a r l e y c o n t r o l d i e t was intake.  (e.g.  due  to h i g h e r p r o t e i n  T h i s i s above the need of the growing p i g .  b a r l e y - s o y b e a n and b a r l e y - a m i n o a c i d d i e t  was  about  (17.6%  the  o f the d i e t )  The p r o t e i n r a t i o 1.5  to  1  of  i n the  - 82 -  present  experiment.  I t was  shown  i n t h i s experiment  to the b a r l e y - l y s i n e d i e t gave  that  0.15%  threonine  added  a n i t r o g e n r e t e n t i o n not  significantly  l e s s than t h a t o b t a i n e d w i t h the b a r l e y - s o y b e a n c o n t r o l b u t  significantly  higher  i n nitrogen retained/nitrogen intake  absorbed.  The  data suggested that a  l y s i n e d i e t may  0.15%  and n i t r o g e n threonine  retained/nitrogen  supplemented b a r l e y -  be a b l e to r e p l a c e p r o t e i n c o n c e n t r a t i o n i n o r d e r  to  s u p p o r t the e q u a l n i t r o g e n r e t e n t i o n . I n n i t r o g e n m e t a b o l i s m e x p e r i m e n t s , t h e r e i s the p o s s i b i l i t y n i t r o g e n l o s s i n f e c e s and u r i n e i f one Martin  (1966)  i n d i c a t e d that  NH^  does n o t t a k e adequate p r e c a u t i o n s .  l o s s from f e c e s was  l o s s e s from u r i n e depended on the. t e m p e r a t u r e and collected.  The  v a l u e below and  28°  C  2.0 and  of  pH  n e g l i g i b l e and a t w h i c h i t was  average l o s s o f n i t r o g e n on c o l l e c t i o n of u r i n e a t a was  . 1.33%  0.97%  when the ambient t e m p e r a t u r e was  a t the l o w e r temperature of  15  to  pH  between  18°  C.  25  The  l o s s e s o f n i t r o g e n from f e c e s and u r i n e s h o u l d have been n e g l i g i b l e i n t h i s e x p e r i m e n t as the u r i n e was below period.  2  "and The  s t o r e d at  c o l l e c t e d i n strong sulphuric acid with a  3° C  u n t i l the end  samples were a n a l y s e d  week c o l l e c t i o n p e r i o d .  pH  o f the one-week c o l l e c t i o n  i m m e d i a t e l y a f t e r the end o f each  one-  -  D.  I t may  -  83  CONCLUSION  be c o n c l u d e d , from the m e t a b o l i s m e x p e r i m e n t t h a t  i s the second l i m i t i n g amino a c i d i n b a r l e y f o r growing p i g s , supporting  threonine  thereby  the r e s u l t s of the growth e x p e r i m e n t .  The  a d d i t i o n of graded l e v e l s of L - t h r e o n i n e  d i e t p r o g r e s s i v e l y improved the n i t r o g e n b a l a n c e ,  of the b a r l e y - l y s i n e  nitrogen balance  adjusted  f o r f e e d i n t a k e and n i t r o g e n i n t a k e , n i t r o g e n r e t a i n e d / n i t r o g e n i n t a k e n i t r o g e n r e t a i n e d / n i t r o g e n absorbed.  A l t h o u g h not a l l r e s u l t s from the  graded .L-threonine  a d d i t i o n s d i f f e r e d s i g n i f i c a n t l y from each o t h e r ,  highest  (0.15%)  threonine  supplemented l e v e l was  the b a s a l b a r l e y - l y s i n e d i e t . of the d i e t ) ,  and  the  s i g n i f i c a n t l y b e t t e r than  A t t h i s l e v e l of t h r e o n i n e  addition  the n i t r o g e n b a l a n c e and n i t r o g e n b a l a n c e a d j u s t e d  (0.52% f o r feed  i n t a k e were s t a t i s t i c a l l y n o n - s i g n i f i c a n t l y d i f f e r e n t from the b a r l e y soybean c o n t r o l d i e t .  A l l threonine  supplemented d i e t s were s i g n i f i c a n t l y  b e t t e r than b a r l e y - s o y b e a n c o n t r o l d i e t i n terms of n i t r o g e n r e t a i n e d / nitrogen intake  and  n i t r o g e n r e t a i n e d / n i t r o g e n absorbed.  o c c u r r e d b e c a u s e the b a r l e y - s o y b e a n d i e t c o n t a i n e d  17.5%  and i n e x c e s s of the r e q u i r e m e n t s of growing p i g s .  The  i n t a k e was  e x c r e t e d i n the u r i n e . T h e r e f o r e  The  T h i s phenomenon crude p r o t e i n ,  excess n i t r o g e n  i t s b i o l o g i c a l v a l u e was  reduced.  m e t h i o n i n e supplement d i d not f u r t h e r improve n i t r o g e n r e t e n -  t i o n i n d i c a t i n g t h a t m e t h i o n i n e was  mot  l i m i t i n g i n the d i e t .  There was  s i g n i f i c a n t d i f f e r e n c e i n dry m a t t e r d i g e s t i b i l i t y between d i e t s .  no  - 84 -  V.  A.  a.  RAT EXPERIMENT I .  EXPERIMENTAL PROCEDURE  General The r e s u l t s o b t a i n e d from P i g E x p e r i m e n t I i n d i c a t e d t h a t t h e  performance of t h e p i g s r e c e i v i n g d i e t s w i t h graded l e v e l s o f t h r e o n i n e added t o t h e b a r l e y - l y s i n e b a s a l d i e t , was s t i l l i n f e r i o r t o t h a t o b t a i n e d w i t h t h e b a r l e y - s o y b e a n c o n t r o l d i e t , a l t h o u g h performance on one o f t h e graded t h r e o n i n e supplemented d i e t was n o t s t a t i s t i c a l l y i n f e r i o r t o t h e performance on t h e c o n t r o l d i e t on t h e b a s i s of Tukey's t e s t ( 1 9 5 3 ) . Conseq u e n t l y i t was c o n s i d e r e d d e s i r a b l e t o i n v e s t i g a t e the e f f e c t o f m o d i f y i n g the l e v e l s o f  amino a c i d s u p p l e m e n t a t i o n on t h e complete removal o f t h i s  gap-  Owing t o the time and expense i n v o l v e d w i t h c a r r y i n g o u t t h i s i n v e s t i g a t i o n w i t h any degree o f thoroughness w i t h p i g s , i t was d e c i d e d t o use r a t s i n t h i s  investigation.  . I t i s g e n e r a l l y known t h a t t h e l a b o r a t o r y r a t has been a c c e p t e d as a s a t i s f a c t o r y p i l o t a n i m a l i n swine n u t r i t i o n r e s e a r c h  as t h e p a t t e r n  o f amino a c i d r e q u i r e m e n t s f o r b o t h s p e c i e s a r e q u i t e s i m i l a r 1968, 1972).  T h i s e x p e r i m e n t was d e s i g n e d as a p r e l i m i n a r y  (N.A.S.-N.R.C.  investigation  to compare t h e r e s p o n s e i n r a t s g i v e n d i e t s s i m i l a r to t h o s e r e c e i v e d by the p i g s i n P i g E x p e r i m e n t I .  I f s i m i l a r growth p a t t e r n s were o b t a i n e d , i t  was i n t e n d e d t o do f u r t h e r e x p e r i m e n t s as f i r s t e x p e r i m e n t s f o r p o s s i b l e  - 85 -  subsequent work w i t h p i g s i n an attempt t o f o r m u l a t e the " i d e a l " b a r l e y amino a c i d  diet.  T h i s e x p e r i m e n t c o n s i s t e d of s i x t r e a t m e n t s w i t h v i d u a l l y housed p e r t r e a t m e n t . for  6  rats  indi-  Three e x t r a r a t s were needed as the c o n t r o l  i n i t i a l body c o m p o s i t i o n a n a l y s i s .  The e x p e r i m e n t was  conducted f o r  26 days.  b.  Animals A t o t a l of  39  a l b i n o male r a t s (Woodlyn/Wistar s t r a i n ) aged  days w i t h average body w e i g h t a p p r o x i m a t e l y  80 g  were employed.  30±1  Thirty-  s i x of t h e s e were, randomly a l l o c a t e d t o i n d i v i d u a l w i r e cages (25.4 x  17.8  2, cm ) .  D i e t s were a s s i g n e d randomly t o the r a t s .  diethylether  Three r a t s were k i l l e d  by  o v e r - a n e s t h e t i z a t i o n and used as c o n t r o l s f o r body c o m p o s i t i o n  analysis. c.  Diets The s i x t e s t d i e t s were o f a s i m i l a r f o r m u l a t i o n t o t h o s e used i n  Pig  E x p e r i m e n t s I and I I  as shown i n T a b l e 2  d i e n t s f o r r a t d i e t s were f i n e l y ground through laboratory m i l l *  d.  .  However, a l l the i n g r e 30 mesh s c r e e n by  C & N  b e f o r e m i x i n g i n a Hobart p l a n e t a r y f e e d m i x e r .  Management  (i)  Housing  Size 8 inches laboratory m i l l ,  C h r i s t y & N o r r i s L t d . , Chelmsford, England.  - 86 -  The e x p e r i m e n t was conducted i n t h e r a t l a b o r a t o r y o f t h e D e p a r t ment o f A n i m a l S c i e n c e , U.B.C. between (ii)  24  to  25° C  The t e m p e r a t u r e o f t h e room was m a i n t a i n e d  throughout the experiment.  F e e d i n g methods  Rats were f e d ad_ l i b i t u m .  Feed was added d a i l y .  F r e s h w a t e r was  p r o v i d e d d a i l y and was a v a i l a b l e c o n t i n u o u s l y from a u t o m a t i c d r i n k e r s ; e.  Records A l l r a t s were w e i g h t e d i n i t i a l l y and t h e r e a f t e r a t  i n t e r v a l s throughout the experiment.  24  hours  D a i l y f e e d consumption was r e c o r d e d .  S p i l l a g e o f f e e d , when i t o c c u r e d , was c o l l e c t e d d a i l y and s u b t r a c t e d from gross i n t a k e .  f.  Chemical a n a l y s i s (i)  Feed  A l l d i e t s were sampled and a n a l y s e d s i m i l a r t o P i g Experiment I . (ii)  Carcass  C o n t r o l r a t s were k i l l e d by d i e t h y l e t h e r o v e r - a n a e s t h e t i z a t i o n at  the b e g i n n i n g o f the experiment.  The g u t o f each r a t was c l e a n e d by  f l u s h i n g w i t h tap water b e f o r e s t o r i n g  at  -10° C  forlater  analysis.  S i m i l a r l y a l l t h e e x p e r i m e n t e d r a t s were k i l l e d a t the end o f t h e f e e d i n g p e r i o d by the same method, c l e a n e d and s t o r e d a t  -10° C .  - 87 -  F o r a n a l y s i s , a l l r a t s were d r i e d a t weighed.  Each d r i e d r a t c a r c a s s was e x t r a c t e d  using s i z e and  43 x 123 mm  ground i n a  C & N  m i l l e d f o r 24 h o u r s .  thimbles.  95° C  i n a soxhlet  72  hours and  apparatus  The c a r c a s s was then d r i e d and weighed  Laboratory m i l l  (30 mesh s c r e e n ) and t h e n b a l l  The powder from the c a r c a s s  d e t e r m i n e p r o t e i n and ash c o n t e n t .  for  sample was then used to  A n a l y s e s were done a c c o r d i n g  to  A.O.A.C. ( 1 9 6 5 ) .  g.  Calculations Average d a i l y gain, feed c o n v e r s i o n  e f f i c i e n c y and average d a i l y  feed i n t a k e o f each r a t was c a l c u l a t e d f o r each week* and t h e o v e r a l l period.  P r o t e i n u l t i l i z a t i o n r a t i o f o r each r a t was a l s o c a l c u l a t e d .  overall  average d a i l y g a i n was used as a c o v a r i a b l e f o r a n a l y s i s o f a l l t h e  carcass  data.  Means o f f a c t o r s w i t h s i g n i f i c a n t  F  The  v a l u e s were t e s t e d by  Tukey's t e s t ( 1 9 5 3 ) . S t a n d a r d e r r o r s o f t r e a t m e n t means were c a l c u l a t e d from a n a l y s i s o f v a r i a n c e t o t a l carcass  tables.  p r o t e i n , protein retention during  protein retained/protein intake i n f a t free carcass, carcass  ash,  The f o u r t h  C a r c a s s a n a l y s e s were used t o c a l c u l a t e  ash %  (%), p r o t e i n %  t h e whole e x p e r i m e n t p e r i o d , i n dry  carcass, protein %  t o t a l carcass  fat,  fat %  i n dry carcass,  i n dry carcass  and  ash %  i n f a t free  "week" was o n l y o f f o u r days  duration.  total  carcass.  - 88 -  h.  Statistical  All computer  Analysis  the  program,  d a t a were UBC-MFAV  A v e r a g e d a i l y g a i n and the  feed  o v e r a l l p e r i o d were  matter  feed  experiment  intake as  a n a l y s e d by a n a l y s i s (Halm and L e , 1974)  covariance  using  a one way c l a s s i f i c a t i o n . for  e a c h week a n d  a n a l y s e d w i t h w e e k l y and o v e r a l l a v e r a g e  covariables. a  for  conversion efficiency  respectively  a v e r a g e d a i l y g a i n as  of  and w e i g h t  at  the b e g i n n i n g o f  C a r c a s s measurement d a t a were  covariable.  for  dry  the  analysed  with  - 89  B.  The weekly and  RESULTS AND  -  DISCUSSION  r e s u l t s o b t a i n e d w i t h r a t s i n average d a i l y g a i n  overall  b a s i s , feed c o n v e r s i o n e f f i c i e n c y  (FCE)  (ADG) and  on  a  overall  p r o t e i n e f f i c i e n c y r a t i o a r e summarized i n T a b l e 8 .  The  a d d i t i o n of  0.444%  d i e t ( b a s a l d i e t ) gave the l o w e s t and  overall  figures while  progressively to  0.15%  The  ADG  a l o n e to the a l l b a r l e y  and p o o r e s t  FCE  on b o t h w e e k l y  the a d d i t i o n of graded l e v e l s o f  ADG  and  FCE.  L - t h r e o n i n e a d d i t i o n than to  ment was added  improved  L-lysine-HCl  n o t s i g n i f i c a n t . The  The  r a t s appeared to respond b e t t e r  0.10%  a d d i t i o n of  a d d i t i o n , but  0.10%  t h r e o n i n e and  0.15%  t h r e o n i n e + 0.10%  were s i g n i f i c a n t b e t t e r then the b a s a l d i e t . FCE  of  rats receiving  0,  0.05,  0.10,  m e t h i o n i n e were 3.09,  the  0.15%  t h r e o n i n e and  3.98,  respectively.  barley-lysine  3.71; The  the p i g s w h i c h r e c e i v e d  4.18,  The  3.51;  t r e n d o b t a i n e d was  0.15%  significantly.  ADG  3.34;  plus 4.55,  with 0.10%  3.21;  the same d i e t s i n P i g Experiment I .  The  (1955).  No  T h i s i s i n agreement w i t h  the r e s u l t s r e p o r t e d  f u r t h e r s i g n i f i c a n t r e s p o n s e to the a d d i t i o n  s u g g e s t s t h a t m e t h i o n i n e i s adequate i n b a r l e y turn  i n d i c a t e d that threonine,  0.10%  DL4.73,  s i m i l a r to t h a t o b t a i n e d  with  rat  growth r e s u l t s i n d i c a t e d t h a t t h r e o n i n e i s a l s o l i m i t i n g i n b a r l e y growing r a t s .  diets and  supplemented  threonine  4.38,  improve-  m e t h i o n i n e added overall  diets  0.15%  the  methionine to  L - t h r e o n i n e improved the r e s p o n s e s l i g h t l y b u t not 0.15%  L-threonine  by  for  the  Sure methionine  f o r the growing r a t .  b u t not m e t h i o n i n e , i s the second  This i n  limiting  Table 8 .  E f f e c t o f amino a c i d supplementation o f low p r o t e i n b a r l e y on average d a i l y gain, feed conversion  1  Barley-soy Week  control  1  lys  e f f i c i e n c y and p r o t e i n e f f i c i e n c y r a t i o o f r a t s  3  4  5  6  3+  B+  B+  B+  Result of SE*  ( B a s a l ) 0.05%Thr 0.10%Thr 0.15%Thr 0.15%Thr+ O.lOZMet.  1  Average Daily  S ~ cance test**  s i  n i f i  5.35  3.36  3.78  4.02  4.27  4.72  ±0.15  16  5 4 3 2  I n i t i a l weight(-) Average feed i n t a k e  5.58  3.68  4.07  4.45  4.47  4.58  tO.20  1 6 5 4 3 2  I n i t i a l weight(-) Average feed i n t a k e  5.25  4.22  4.26  4.50  4.71  4.83  ±0.21  Gain(g)  overall period Feed Conversion Efficiency g feed 8 gain  3  Significant covariables  5.47  4.24  4.42  4.60  4.81  5.11  ±0.26  5.28  3.98  4.18  4.38  4.55  4.73  ±0.10  2.30  3.77  3.30  3.08  3.02  2.67  2.49  3.96  3.49  3.23  3.20  .  N.S.  Average feed  N.S.  I n i t i a l weight(-) Average feed i n t a k e  1 6 5 4 3 2  I n i t i a l weight(-) Average feed i n t a k e  ±0.13  2 3 4 5 6 1  I n i t i a l weight Average feed i n t a k e  3.11  ±0.16  2 3 4 5 6 1  I n i t i a l weight  3.15  3.74  3.95  3.65  3.43  3.31  ±0.23  N.S.  N.S.  3.07  3.90  3.90  3.61  3.41  3.27  ±0.22  N.S.  N.S.  2.79  3.71  3.51  3.34  3.21  3.09  ±0.07 0.07  Initial weight  84  78  78  86  77  79  ±2.81  Protein Efficiency Ratio  2.03  2.36  2.48  2.63  2.69  2.80  ±0.06  ^  overall period  intake  2_3 4 5 6 1  I n i t i a l weight  N.S.  6 5 4 3 2 1  N.S.  Computed from 5 days d a t a . Standard e r r o r o f treatment means.  ** Treatment means not u n d e r s c o r e d by the same l i n e are s i g n i f i c a n t l y d i f f e r e n t a t the 5% l e v e l o f probaoility (Tukey, 1953).  - 91 -  amino a c i d i n b a r l e y .  The o v e r a l l  ADG  on t h e b a r l e y - s o y b e a n  control diet  was s i g n i f i c a n t l y b e t t e r than t h e g a i n on any amino a c i d - s u p p l e m e n t e d b a r l e y d i e t w h i c h tends t o show t h a t a t these l e v e l s o f amino a c i d a d d i t i o n to b a r l e y , p r o t e i n r e q u i r e m e n t s s t i l l were n o t a d e q u a t e l y the  0.15%  produced a diet.  threonine plus FCE  0.10%  met.  However,  m e t h i o n i n e a d d i t i o n t o the b a s a l d i e t  t  w h i c h d i d n o t d i f f e r s i g n i f i c a n t l y from t h a t o f the c o n t r o l  I n t h i s c a s e , m e t h i o n i n e d i d show an e f f e c t by i m p r o v i n g  "FCE  of  the growing r a t s .  The w e e k l y  ADG  showed t h a t t h e p r o t e i n and amino a c i d r e q u i r e -  ments d e c r e a s e d as t h e age o f r a t i n c r e a s e d . higher l e v e l s of threonine supplementation trial.  There was no s i g n i f i c a n t respond  two weeks. confirms  The r a t s had responded t o t h e  d u r i n g the f i r s t two weeks on t o the h i g h e r l e v e l s i n t h e l a t t e r  T h i s r e d u c t i o n i n p r o t e i n s and amino a c i d r e q u i r e m e n t s w i t h age  t h e work  o f Forbes and Rao  (1959)  and  H a r t s o o k and M i t c h e l l  (1956).  The w e e k l y required  per  unit  a l l the t r e a t m e n t s .  FCE of The  r e s u l t s i n d i c a t e d t h a t more u n i t s o f feed were g a i n as age i n c r e a s e d . 0.15%  T h i s g e n e r a l l y appeared i n  threonine plus  0.10%  mented d i e t and t h e c o n t r o l d i e t showed the b e s t s i g n i f i c a n t l y from each o t h e r . the  0.10%  and  0.15%  FCE,  methionine  and d i d n o t d i f f e r  The former d i e t a l s o d i d n o t d i f f e r  threonine a d d i t i o n d i e t s .  more f e e d p e r u n i t g a i n than a l l o t h e r t r e a t m e n t s .  supple-  from  The b a s a l d i e t r e q u i r e d The f a c t t h a t  threonine  and m e t h i o n i n e added t o t h e b a s a l d i e t produced a FCE s i m i l a r t o the c o n t r o l i n d i c a t e d t h a t a low p r o t e i n d i e t  (about  11%  crude p r o t e i n )  with a  - 92 -  p r o p e r amino a c i d b a l a n c e can p e r f o r m as w e l l as a h i g h e r p r o t e i n d i e t (about  17.5%  crude p r o t e i n )  containing a conventional protein  supplement. The p r o t e i n e f f i c i e n c y r a t i o  (PER)  was  improved p r o g r e s s i v e l y  w i t h an i n c r e a s e i n the l e v e l o f t h r e o n i n e s u p p l e m e n t a t i o n .  Diets with  0.10%  PER  o r over t h r e o n i n e a d d i t i o n gave s i g n i f i c a n t l y b e t t e r  than the b a s a l d i e t  i n d i c a t i n g t h r e o n i n e t o be l i m i t i n g i n the b a s a l d i e t .  T h i s agrees w i t h the  ADG  and  FCE  r e s u l t s and i n d i c a t e s t h a t t h r e o n i n e  i s the second l i m i t i n g amino a c i d i n b a r l e y f o r growing  The b a r l e y - s o y b e a n a l t h o u g h the  ADG  values  and  FCE  rats.  c o n t r o l d i e t produced the p o o r e s t were the b e s t based on t h i s d i e t .  PER This i s  p r o b a b l y b e c a u s e t h e c o n t r o l d i e t c o n t a i n e d a h i g h e r crude p r o t e i n l e v e l than r e q u i r e d p e r s e . (1956)  who  decreased  The r e s u l t s agree w i t h those o f  M e t t a and  Mitchell  i n d i c a t e d t h a t the b i o l o g i c a l v a l u e of d i f f e r e n t p r o t e i n  l i n e a r l y as the p r o t e i n c o n c e n t r a t i o n i n the d i e t i n c r e a s e d .  Covariance r e l a t i o n s h i p between  a n a l y s i s showed t h a t t h e r e was ADG  a significant  and i n i t i a l w e i g h t and between  FCE  negative  and  feed  Intake.  The  r a t c a r c a s s a n a l y s i s d a t a a r e summarized i n T a b l e 9 .  No  s i g n i f i c a n t d i f f e r e n c e s i n t o t a l p r o t e i n r e t e n t i o n were o b t a i n e d among the control,  0.10%  added d i e t s .  t h r e o n i n e and  L e v e l s of  0.10%  0.15%  threonine plus  0.10%  methionine  t h r e o n i n e o r h i g h e r produced s i g n i f i c a n t l y  b e t t e r p r o t e i n r e t e n t i o n than the b a s a l d i e t .  No s i g n i f i c a n t d i f f e r e n c e s  Table 9 . Effect of amino acid supplementation  of low protein barley on carcass  characteristics of rats.  Barley-soy lys B+ B + B+ B+ control (Basal) 0.05%thr 0.10%thr 0.15%thr 0.15%thr+ 0.10%met  Total carcass protein(g)  Result of signifiSE* ^"r**  Significant covariable  1  38.31  29.96  31.82  35.07  33.26  34.25  +1.17  14 5 6 3 2  N.S.  28.07  19.72  21.58  24.82  23.03  24.01  ± 1.17  14 6 5 3 2  N.S.  Protein retained Protein intake  45.29  44.51  47.73  54.47  52.07  55.93  + 2.21  6 4 5 3 12  N.S.  Protein % i n dry carcass  63.02  48.62  53.18  53.60  53.21  60.42+1.51  16 4 5 3 2  Protein % i n f a t free carcass  81.46  80.26  80.21  81.66  80.54  81.00  + 0.53  N.S.  N.S.  Total carcass fat (g)  13.21  23.07  20.63  22.79  21.55  14.29  ± 1.47  2 4 5 3 6 1  Average daily gain  Fat % i n dry carcass  22.37  38.37  33.85  34.30  33.81  25.32  + 1.60  2 4 3 5 6 1  Average daily gain  Total carcass ash (g)  6.48  5.42  5.72  6.06  6.03  5.99  + 0.17  Ash % i n dry carcass  10.78  8.94  9.57  9.30  9.68  10.61  + 0.26  Ash % i n fat free carcass  13.88  14.51  14.47  14.13  14.62  14.21  ± 0.16  N.S.  N.S.  Protein+fat+ash % Dry carcass wt  96.39  96.75  96.46  97;12  96.77  96.43  + 0.39  N.S.  N.S.  Protein retention during 26 days on t r i a l (g)  N.S. 1 6 5 3-4 2  Average dally gain(-)  N.S. Average daily gain(-)  Standard error of treatment means. Treatment means not underscored by the same line are s i g n i f i c a n t l y different at the 5% l e v e l of probability (Tukey, 1953)  - 94  were o b t a i n e d  among the t h r e o n i n e  t h a t the b a r l e y - l y s i n e d i e t was  -  supplemented d i e t s .  l i m i t i n g i n threonine.  as p e r c e n t a g e o f p r o t e i n i n t a k e was  Hie r e s u l t s i n d i c a t e The p r o t e i n r e t a i n e d  p r o g r e s s i v e l y improved by  a d d i t i o n , s i m i l a r i n manner t o improvements i n PER.  threonine  The m e t h i o n i n e supplemen-  t e d d i e t appeared to produce a h i g h e r p r o t e i n r e t a i n e d / p r o t e i n i n t a k e but  the d i f f e r e n c e was  (1953)  test.  n o t s i g n i f i c a n t l y d i f f e r e n t as measured by  value  Tukey's  The b a r l e y - s o y b e a n c o n t r o l d i e t r e s u l t e d the p o o r e s t  value  i n d i c a t i n g an e x c e s s p r o t e i n i n t a k e .  C a r c a s s f a t was supplemented group. carcass  The  l o w e s t i n b o t h the c o n t r o l group and a d d i t i o n of t h r e o n i n e had  f a t content obtained  no v a r i a t i o n w i t h  The  no i n f l u e n c e on the  on the b a r l e y - l y s i n e d i e t .  high  T o t a l ash showed  treatment.  threonine  p l u s m e t h i o n i n e supplemented d i e t r e s u l t e d i n  s i g n i f i c a n t l y lower carcass  fat.  e f f e c t i v e l y reduced t o t a l carcass backfat  the m e t h i o n i n e  t h i c k n e s s was  This i n d i c a t e d that methionine a d d i t i o n f a t i n growing r a t s .  not reduced i n the p r e v i o u s  w i t h the same l e v e l of m e t h i o n i n e s u p p l e m e n t a t i o n .  However, t o t a l  pig nutritional  trial  This evidence suggests  t h a t the g r o w i n g r a t can p r o b a b l y u l t i l i z e t h i s l e v e l o f m e t h i o n i n e e f f e c t i v e l y t h e n the g r o w i n g - f i n i s h i n g p i g by resulting i n less fat deposition.  enhancing n i t r o g e n  Thus, the growing r a t s do not  w e l l w i t h the g r o w i n g - f i n i s h i n g p i g s i n t h i s  respect.  more  retention correlate  C.  The r e s u l t s of the  CONCLUSION  rat  experiments  i n d i c a t e a r a t response  s i m i l a r t o t h a t g i v e n by p i g s i n P i g Experiment  I.  The a d d i t i o n to the  b a r l e y - l y s i n e d i e t o f graded t h r e o n i n e l e v e l s improved PER  o f the r a t .  The  the  ADG,  FCE  f u r t h e r a d d i t i o n o f m e t h i o n i n e d i d n o t improve  above c r i t e r i a s i g n i f i c a n t l y .  The c a r c a s s p r o t e i n r e t e n t i o n ,  and the  expressed  e i t h e r i n a b s o l u t e terms o r as a p e r c e n t a g e of p r o t e i n i n t a k e a l s o gave results i n strong  f a v o r of t h r e o n i n e s u p p l e m e n t a t i o n .  evidence  that  The d a t a measured gave  t h r e o n i n e i s the second l i m i t i n g amino a c i d i n  b a r l e y f o r growing r a t s .  The r e s u l t i s i n agreement w i t h the p i g  experiments.  C a r c a s s f a t was  l o w e s t i n the c o n t r o l group and t h e m e t h i o n i n e  supplemented  group.  However, t h e r e s u l t s o b t a i n e d from the m e t h i o n i n e  supplemented  group of r a t s , of low c a r c a s s f a t and h i g h p r o t e i n r e t e n t i o n ,  d i d n o t o c c u r i n the p i g s .  F a t c o n t e n t i n the r a t was t i o n o f the b a r l e y - l y s i n e d i e t .  n o t reduced by t h r e o n i n e  supplementa-  T o t a l ash d i d n o t v a r y w i t h t r e a t m e n t .  - 96 -  VI.  A.  a.  RAT EXPERIMENT I I  EXPERIMENTAL PROCEDURE  General Results  of Rat Experiment I  i n d i c a t e d that the response i n r a t s  to amino a c i d s u p p l e m e n t a t i o n o f b a r l e y was somewhat pigs.  However t h e r e were q u a n t i t a t i v e d i f f e r e n c e s  s i m i l a r to that i n  i n t h a t t h e r a t s appeared  t o be r e s p o n d i n g to the h i g h e r l e v e l o f t h r e o n i n e and, a t l e a s t i n t h e f i r s t week,  growth and  a d d i t i o n of methionine. plus  0.10%  c a r c a s s c o m p o s i t i o n were r e s p o n d i n g t o t h e However, i t was o b v i o u s t h a t even  0.15%  threonine  m e t h i o n i n e a d d i t i o n d i d n o t g i v e o p t i m a l performance.  T h i s e x p e r i m e n t was d e s i g n e d to i n v e s t i g a t e the e f f e c t o f an improved c o n t r o l d i e t ( h i g h e r p r o t e i n ) A d d i t i o n a l t h r e o n i n e and the b a r l e y  (4)  (2)  Additional lysine  (1) (3)  The p r o v i s i o n o f an amino a c i d s m i x t u r e t o  d i e t on r a t growth and c a r c a s s c o m p o s i t i o n .  The e x p e r i m e n t a l d e s i g n c o n s i s t e d were f e d f o r 4  weeks.  of  48  a l b i n o male r a t s w h i c h  Four e x t r a r a t s were s l a u g h t e d a t the b e g i n n i n g  of t h e e x p e r i m e n t as an i n i t i a l c o n t r o l group f o r t h e assessment o f body nutrient  b.  storage.  Animals A t o t a l of  52  a l b i n o male r a t s  (Woodlyn/Wistar s t r a i n )  -  average weight  86 g  97  -  and age 30 ± 1 days were used.  Method of a l l o c a t i o n  of rats was s i m i l a r to that used i n Rat Experiment I. c.  Diets The d i e t formulation i s  shown i n Table 10.  The amino acid  mixture was formulated to provide a s l i g h t margin of each of the e s s e n t i a l amino acids over requirement .levels lis.ted i n "Nutrient Requirements of Laboratory Animals."  N.A.S.-N.R.C (1972).  The l i s t e d requirements f o r  non-essential amino acids were not adhered to as these had been merely calculated  from l e v e l s included i n "successful" d i e t s , and thus were not  shown to be e s s e n t i a l . was  1.75%.  Total l e v e l of added amino acid mixture ( a i r dry basis)  The composition of the added amino acid mixture and treatments  were given below.  The amino acid content of each d i e t i s shown i n Table 11.  Amino acid mixture L-arginine  0.20%  L-tryptophan L-histidine L-leucine  0.05% 0.20%  0.20%  L-isoleucine  0.20%  L-phenylalanine DL-methionine L-valine  0.30%  0.20%  0.10%  L-Glutamic acid  0.30%  - 98 -  Treatments  d.  1.  Barley only to supply  2.  B a r l e y + soybean meal t o s u p p l y  0.75%  total  lysine.  3.  B a r l e y + soybean meal t o s u p p l y  0.90%  total  lysine.  4.  B a r l e y + 0.637% L - l y s i n e - H C l t o s u p p l y  0.90%  total  5.  B a r l e y + 0.444% + 0.10%  L-threonine. L-threonine  6.  Diet  5+0.10%  7.  Diet  4 + 0.10%  L-threonine.  8.  Diet  4 + 0.20%  L-threonine.  9.  Diet  5 + amino a c i d  mixture.  10.  Diet  6 + amino a c i d  mixture.  11.  Diet  7 + amino a c i d  mixture.  12.  Diet  8 + amino a c i d  mixture.  Management  Records Same as Rat E x p e r i m e n t 1.  f.  total  lysine.  L - l y s i n e - H C l to supply  Same as Rat E x p e r i m e n t I .  e.  0.41%  Chemical A n a l y s i s Same as Rat Experiment I .  0.75% t o t a l  ( i . e . 0.20% added  lysine. lysine  L-threonine)  _ 99  g.  Calculations Same as R a t E x p e r i m e n t I .  h.  Statistical  Analysis  Same as R a t Experiment I .  -  Table 10.  P e r c e n t a g e c o m p o s i t i o n o f d i e t s used i n Rat Experiment I I  ( A i r dry b a s i s )  D i e t No.  Ingredients 1  2  3  4  5  6  7  8  9  10  11  12  96.82 81.34 75.16 96.19 96.23 96.18 96.04 95.99 94.63 94.43 94.34 94.24  Barley Soybean meal L - l y s i n e HC1*  -  L-threonine*  -  L-Arginine*  L-histidine*  -  L-leucine*  -  L-tryptophan*  DL-me t h i o n i n e *  -  L-valine*  -  L-isoleucine* L-phenylalanine*  L-glutamic  acid*  -  15.60 21.80  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  0.637 0.444 0.444 0.637 0.637 0.444 0.444 0.637 0.637  -  0.10  0.20  0.10  0.20  6.10  0.20  0.10  0.20  -  -  -  0.20  0.20  0.20  0.20  0.05  0.05  0.05  0.05  0.20  0.20  0.20  0.20  6.20  0.20  0.20  0.20  -  0.20  0.20  0.20  0.20  -  0.30  0.30  0.30  0.30  0.20  0.20  0.20  0.20  6.10  0.10  0.10  0.10  -  -  -  -  -  0.30  0.30  0.30  0.30  -  -  -  -  -  T r a c e m i n e r a l and v i t a m i n promix  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  D e f l u o r i n a t e d rock phosphate  1.64  1.49  1.42  1.64  1.64  1.64  1.64  1.64  1.64  1.64  1.64  1.64  Limes tone  0.54  0.57  0.62  0.54  0.54  0.54  0.54  0.54  0.54  0.54  0.54  0.54  Iodized  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  salt  The c o m p o s i t i o n o f t r a c e m i n e r a l and v i t a m i n premix i s same as t h a t used i n P i g E x p e r i m e n t s I , I I and R a t E x p e r i m e n t I . The L - l y s i n e HC1 was fyed grade and was was p u r e and DL-methionine was 98% p u r e .  98% p u r e , c o n t a i n i n g 78% L - l y s i n e . The t h r e o n i n e A l l were produced by the Ajinomoto Co., Japan.  Table 11.  Content o f e s s e n t i a l amino a c i d s o f each d i e t f o r Rat Experiment I I (g amino a c i d / l O O g mixed feed) on a i r d r y b a s i s .  D i e t No Amino  Acid  11  12  0 .64  0 .64  0,.64  0. 40  0 .40  0 .40  0.,40  0 .40  0. 59  0 .59  0 .59  0,.59  0 .73  0 .73  0. 91  0 .91  0 .91  0,.91  0 .75  0 .90  0 .90  0. 75  0 .75  0 .90  0,.90  0 .17  0 .17  0 .17  0 .17  0. 36  0 .36  0 .36  0,.36  0 .20  0 .20  0 .20  0 .20  0 .20  0. 20  0 .20  0 .20  0,.20  0,.90  0 .53  0 .53  0 .53  0 .53  0 .53  0. 82  0 .82  0 .82  0,.82  0..48  0..55  0 .28  0 .28  0 .28  0 .28  0 .28  0. 28  0 .28  0 .28  0,.28  0 .37  0..56  0,.63  0 .37  0 .47  0 .57  0 .47  0 .57  0. 47  0 .57  0 .47  0,.57  Tryptophan  0 .11  0..19  0,.23  0 .11  0 .11  0 .11  0 .11  0 .11  0. 16  0 .16  0 .16  0,.16  Valine  0 .68  0..86  0,.93  0 .68  0 .68  0 .68  0 .68  0 .68  0. 76  0 .76  0 .76  0,.76  2 .36  2.,97  3,.21  2 .36  2 .36  2 .36  2 .36  2 .36  2. 60  2 .60  2 .60  2,.60  Dry m a t t e r content %  89 .93 90.,26 90,.34 89 .76 89 .75 90 .22 90 .22 89 .74 90. 47 89 .91 90 .21  90,.13  Crude p r o t e n t % (N x 6.25)  10 .93 17..91 19,.35 11 .54 11 .81 11 .38 11 .39 11 .66 12. 58 12 .58 12 .99  12,.93  1  2  3  4  5  6  7  8  9i  10  Arginine  0 .45  0..82  0..96  0 .45  0 .45  0 .45  0 .45  0 .45  0. 64  Histidine  0 .21  0..40  0..48  0 .21  0 .21  0 .21  0 .21  0 .21  Isoleucine  0 .40  0,.58  0,.66  0 .40  0 .40  0 .40  0 .40  Leucine  0 .73  1..18  1,.36  0 .73  0 .73  0 .73  Lysine  0 .41  0 .75  0,.90  0 .90  0 .75  Methionine  0 .17  0..24  0,.27  0 .17  0 .20  0,.27  0,.29  0 .53  0.,80  0 .28  Threonine  (Cystine)* Phenylalanine (Tyrosine)*  Glutamic  acid**  S e m i - e s s e n t i a l amino a c i d N o n - e s s e n t i a l amino a c i d  - 102  B.  The  FCE  and  PER  R a t s f e d a s o l e b a r l e y d i e t gave the p o o r e s t  ADG,  FCE  above c r i t e r i a were improved by  and  ADG,  are  addition  of l y s i n e a l o n e .  and  PER.  Further  v a r i o u s l e v e l s of graded l y s i n e , t h r e o n i n e  o t h e r amino a c i d m i x t u r e s .  0.10%  and  W i t h the  0.444%  0.20%  threonine  t i o n gave s i m i l a r increasing  improvement was increasing  the  ADG  and  lysine-HCl (diets 5 FCE,  and  i.e.  t h r e o n i n e l e v e l from  o b t a i n e d based on  0.75%  l y s i n e was  d i e t when the  l y s i n e l e v e l was  0.10%  higher requirement  diets 9  to  0.20%.  0.75%  g r e a t e r on  0.90%  to  11  no  by The  the  0.20%  results  of  P i c k and  of the  and  added t h r e o n i n e 0.75%.  These  Meade (1970) 0.70%  of  who the  N.A.S.-N.R.C. (1972) i n d i c a t e  diet).  s u p p l e m e n t a t i o n of amino a c i d m i x t u r e s to d i e t s 5 and  obtained  In addition,  0.90%.  than when i t was  findings  e t a l . (1959)  (0.90%  supplementa-  l e v e l s of threonine  l y s i n e r e q u i r e m e n t o f growing r a t s was  d i e t a l t h o u g h Rama Rao  The  respectively)  diet),  adequate f o r growing r a t s , a l t h o u g h i n  r e s u l t s are i n agreement w i t h the r e p o r t e d t h a t the  6  (0.75% o f the  no b e n e f i c i a l e f f e c t was  t h e s e two  f i r s t week d a i l y growth r a t e was  (i.e.  added d i e t  l y s i n e l e v e l s of the d i e t s from  suggests that the  for  12  improvements were o b t a i n e d by  by  DISCUSSION  r e s u l t s of the e x p e r i m e n t  summarized i n T a b l e  The  RESULTS AND  -  respectively)  d i d not  improve  ADG  and  and  6 FCE  a  Table 12.  1 Week  E f f e c t of amino acid ftupplcMntaelon of low p r o t e i n barley on average d o l l y g a i n , feed  2  Barley Barley-soy (0.75Jlya> only (Basal)  2.83  3.76  3  4  Barley-aoy (0.90Uya)  B + lye(0.90Z)  5.90  3.21  i  » +  6  lye(0.75J)+ 0.10Z t h r .  B + lys(0.73Z)+ 0.20X t h r .  4.06  J.59  7 B + lys(0.901)+ 0.10Z t h r .  conversion e f f i c i e n c y end protein e f f i c i e n c y r a t i o ot r a r a .  8 B + lys(0.90I) 0.20X t h r .  B + lys(0.75I)+ 0.10X thr + amino acid mixture  10  11  12  B + lys(0.75X)+ 0.201 thr + amino acid mixture  B + lya(0.90Z)+ 0.10X thr + amioo a d d mixture  B + lys(0.90Z)+ 0.20X thr + aalDo acid mixture  5.38  3.7*  SE*  10.15  Result of Blgnlfleance t e a t * *  3 2 12 10 8 11 9 5 7 6 4 1  I n i t i a l velght(-) Average feed intake  Average  Daily  Cain  Significant covariable.  1.40  5.85  3.37  3.60  2.70  6.03  5.62  3.48  6.12  10.22  12 2 10 3 5 8 11 6 7 9 4 1  5.51  10.22  2 10 3 12 9 11 8 6 7 5 4 1  Avareg. feed Intake  (g) 4.78  I n i t i a l velght(-) Average feed intake  Overall period  2.67  3.38  4.94  10.25  3 2 10 12 9 11 3 6 8 4 7 1  I n i t i a l velght(-) Average feed intake  3.32  5.41  3.15  10.09  2 3 10 12 9 11 8 3 6 7 4 1  I n i t i a l velght(-) Average feed Intake  4.36  2.23  2.40  10.23  4 1 6 7 3 9 11 8 10 12 2 3 '  Average feed intake(-)  4.40  2.55  2.46  10.17  1 4 9 7 6  5.39  2.43  3.79  2.81  4.31  2.73  2.17  4.61  2.93  2.88  reed Conversion  2  11 8 3 3  10 2 12  U.S.  Efficiency 2.69  4.30  4.01  3.48  2.81  10.19  1_4 5 7 6 11 9 8 12 10 3 2 I n i t i a l velght — A v e r a g e feed lntake(-)  4.91  4.17  4.37  3.14  D0.31  1 8 4 7 6 5 11 9 12 10 2 3 — H Z Z Z m ^ Z ^ » ^ „ .  I n i t i a l velght Average feed lntake(-)  2.92  10.06  1, 4 7 6 5 6 11 9 12 10 3 2 —  I n l t l e l velght Averege feed lnteke(-)  87  12.20  2.66  10.03  10 12 8 6 9 5 7 11 4 1 2 3 — — A v e r e  I n i t i a l velght g e feed lotake(-)  g gain  Ore r a i l period  3.45  2.92  Initial weight Protein Efficiency Ratio  2.23  2.03  Standard e r r o r of tr.atment  2.43  2.32  means.  Treatment means not underscored by the same l i n e a n s l g n l f i c a n t l y d i f f e r e n t at the 31 l e v e l of p r o b e b i l i t y (Tukey 1953). ;  - 104 -  significantly. 8  However, the a d d i t i o n o f amino a c i d m i x t u r e s t o d i e t s 6 and  ( i . e . d i e t s 10 and  cantly better  12  respectively)  gave r e s u l t s w h i c h were s i g n i f i -  than t h o s e o b t a i n e d w i t h a l l o t h e r b a r l e y - a m i n o a c i d  diets.  M o r e o v e r , the r e s u l t s o b t a i n e d w i t h t h e s e two d i e t s were e q u i v a l e n t t o those r e s u l t i n g from the b a r l e y - s o y b e a n d i e t s  (diets 2  When comparing a l l the d i e t s c o n t a i n i n g d i e t s 5, 6, 9 and  10),  threonine respectively improvement o f d i e t 6  d i e t s 5 and has s i m i l a r  0.75%  containing  ADG  and  FCE.  0.10% 0.20%  t h e r e b y i m p r o v i n g the  FCE  ADG  and  added  and  D i e t 12  brought the d i e t i n t o proper balance, dramatically.  contained  I n c r e a s i n g the  0.90%  Higher l y s i n e  addition  ADG  as i n  and  l y s i n e and  The e v i d e n c e f u r t h e r comfirmed t h a t  i n this barley barley  d i e t f o r the growing r a t s .  diet containing  0.90%  addition of (or  0.57%  Again  0.20%  with  threonine 0.75%  l y s i n e was s u f f i c i e n t  0.10%  t h r e o n i n e added t o the  l y s i n e p l u s amino a c i d m i x t u r e  gave i n f e r i o r r e s u l t t o those w i t h acid mixture.  0.75%  FCE  0.20%  p l u s amino a c i d m i x t u r e s gave the r e s u l t s i m i l a r t o d i e t 10 lysine.  0.20%  However, the marked  threonine.  w i t h amino a c i d m i x t u r e d i d n o t f u r t h e r improve t h e 12.  0.10%  t h r e o n i n e became l i m i t i n g when the amino a c i d m i x t u r e  supplemented t h r e o n i n e l e v e l t o  and  lysine ( i . e .  w i t h s i m i l a r amino a c i d m i x t u r e a d d i t i o n .  was added t o the d i e t c o n t a i n i n g  d i e t s 11  3).  a f t e r a d d i t i o n o f t h e amino a c i d m i x t u r e and r e l a -  t i v e l y no improvement i n d i e t 5 tend t o s u g g e s t t h a t  6  and  ( d i e t 11)  added t h r e o n i n e p l u s t h e amino  The o b s e r v a t i o n s u g g e s t e d t h a t w i t h the amino a c i d m i x t u r e , 0.20%  t h r e o n i n e must be r e q u i r e d  t o t a l threonine)  i n this barley  diet  i n order to a t t a i n the proper balance.  However, t h i s b a l a n c e c o u l d n o t be a t t a i n e d w i t h o u t the amino a c i d mixture.  - 105 -  supplementation.  The r e s u l t s o b t a i n e d w i t h d i e t s 10  and  12  were s i m i l a r t o t h e  r e s u l t s o b t a i n e d w i t h t h e b a r l e y - s o y b e a n d i e t , i n d i c a t i n g t h a t optimum and  FCE  diet.  c a n b e a c h i e v e d by amino a c i d s s u p p l e m e n t a t i o n o f t h e b a r l e y  The adequacy o f t h e 0.52%  t h r e o n i n e i n t h e d i e t f o r o p t i m a l growth  was i n agreement w i t h t h e r e p o r t s by (1959)  ADG  N.A.S.-N.R.C. (1972) and Rama Rao e t a l .  b u t lower than l e v e l s suggested by  Rosenberg j2t a l .  (1959)  P i c k and Meade ( 1 9 7 1 ) .  studied the e f f e c t of supplementation  o f r i c e d i e t w i t h l y s i n e and t h r e o n i n e and i n d i c a t e d t h a t t h e r a t i o o f t o t a l l y s i n e t o t o t a l t h r e o n i n e i n t h e d i e t f o r optimum response was by w e i g h t . and of  10  i n the present experiment. or  2.01 : 1  f o r the growing  to  diet 2  0.90%, 0.63%  and  Rose e t a l .  rats.  t h e maximum growth.  and t h r e o n i n e o f  (2) c o n t a i n i n g  17.9% crude p r o t e i n  F u r t h e r i n c r e a s i n g t h e p r o t e i n l e v e l ( d i e t 3)  were  0.75%, 0.56%  and  FCE.  The l y s i n e  r e s p e c t i v e l y and o f d i e t 3  respectively.  The- o v e r a l l r e s u l t s f o r ADG 12  Rose (1937)  19.4% crude p r o t e i n d i d n o t improve t h e ADG  were  1  However, t h i s d i f f e r e d from t h e r a t i o s  s u g g e s t e d by  The b a r l e y - s o y b e a n d i e t produced  to  T h i s r a t i o was c o i n c i d e n t l y i n agreement w i t h d i e t s 2, 3, 6  1.66 : 1  (1949)  1.4  and  FCE  o f d i e t s 2, 3, 10 and  were s i g n i f i c a n t l y b e t t e r than those o f any o t h e r b a r l e y - a m i n o  acid  diets.  D i e t s 10  and  12  gave t h e b e s t  PER  b u t v a l u e s were n o t  - 106  -  s i g n i f i c a n t l y b e t t e r than those of d i e t s 6 and s i g n i f i c a n t l y b e t t e r than the o t h e r t h r e o n i n e  8. The and  l y s i n e supplemented d i e t s  b u t were s i g n i f i c a n t l y b e t t e r t h a n v a l u e s o b t a i n e d supplemented d i e t and  the s o l e b a r l e y d i e t .  produced the p o o r e s t  PER's  of n o n - e s s e n t i a l d i e t s 10  and  The  nitrogen.  12  was  w i t h the  due  carcass  the h i g h e s t  6.  13  protein retention  ( e x c e p t f o r the s o l e b a r l e y d i e t )  but  i n terms o f  As w i t h the  PER  h i g h i n t a k e of p r o t e i n produced s m a l l e r  f o r p r o t e i n r e t a i n e d as p e r c e n t a g e of p r o t e i n i n t a k e . had  and  of  a n a l y s i s r e s u l t s are presented i n Table  p r o t e i n r e t a i n e d as a p e r c e n t a g e of p r o t e i n i n t a k e . f i g u r e s , the u n n e c e s s a r i l y  intakes  r e s u l t s i n d i c a t e d t h a t the p r o t e i n  B a r l e y - s o y b e a n meal d i e t s gave the h i g h e s t gave the l o w e s t f i g u r e s  lysine  t o the h i g h  b e s t u t i l i z e d f o l l o w e d by d i e t s 8  r a t s carcass  0.90%  The b a r l e y - s o y b e a n d i e t s  as i n Rat Experiment I The  l a t t e r d i e t s were n o t  D i e t s 10  values  and  12  p r o t e i n r e t e n t i o n and p r o t e i n r e t a i n e d as p e r c e n t a g e o f  p r o t e i n i n t a k e when compared w i t h a l l o t h e r b a r l e y - a m i n o a c i d d i e t s . s o l e b a r l e y d i e t gave l o w e s t p r o t e i n r e t e n t i o n and p r o t e i n intake.  S i m i l a r t o the p i c t u r e p r o d u c e d by  obtained  with  PER  figures, results  t o b a r l e y improved the above  A d d i t i o n of graded l e v e l s of t h r e o n i n e  performance.  retained/protein  the b a r l e y amino a c i d d i e t s tended t o i n d i c a t e t h a t a d d i t i o n  of the f i r s t l i m i t i n g amino a c i d l y s i n e criteria.  the  The  Increasing  not f u r t h e r improve  d i e t a r y l y s i n e l e v e l from  performance.  f u r t h e r improved 0.75%  to  This again suggested t h a t  the  0.90% 0.75%  i s s u f f i c i e n t f o r the growing r a t .  C a r c a s s f a t c o n t e n t was  negatively  correlated with  protein  did lysine  Table 1). E f f e c t of n t n o acta" e u p p l c M n t a t l o n o f low protein barley on carcase c h a r a c t e r U t l c s  2  1 Barley only (Basal)  T o t a l carcaaa proteln(g)  32.25  Barley-aoy (0.752lya)  . 41.31  Protein retention during 28 days oo t r i a l (g) Protein retained j Protein intake  4  5  6  7  8  Barlcy-aoy (0.90Ztyo)  B + lys(0.901)  B + l y s (0.751) •tO.lOXthr  B • lys(0.751) +0.20Zthr  B + lyo(0.90Z) +0.10Zthr  B + lys(0.90Z) 4O.20Zthr  40.44  34.29  35.66  37.63  28.64  22.49  38.81  41.49  63.79  48.37  31.57  57.14  3  48.96  of r a t e  9  51.14  B + lyo(0.73Z) +0.10Zthr+ amino acid mixture  51.63  10  11  12  B + lya(0.752) 4O.20Zthr+ emlno acid mixture  B + lys(0.90Z) +0.10Zthr+ amino acid mixture  8 + lra(0.90Z) +0.202 th r+ offline acid mixture  38.83  SE*  Result of significance  Significant covariable  test**  39.92  z 0.89  2 10 3 12 9 6 8 11 7 3 4 1 •  Average d a i l y gain  28.15  t 0.89  2 10 3 12 9 11 8 3 6 7 4 1 —  Averege d a i l y gain  55.90  1 1.34  10 12 9 6 8 7 11 5 2 4 3 1  Average d a i l y gain  61.78  i 1.72  2 3 10 9 12 8 11 6 7 5 4 1  Averege d a i l y 8aln(-)  Protein Z i n dry carcase  41.81  P r o t e i n Z In fat free carcaaa  77.90  83.19  83.09  79.93  80.37  80.73  80.37  80.82  80.18  82.98.  81.82  81.61  ± 0.66  T o t a l carcass fat(g)  31.73  9.65  12.04  26.18  24.87  19.52  21.26  16.41  13.05  13.56  19.22  15.53  x 1.63  1 4 3 7 6 11 B 12 9 10 3 2 —  Averege d a l l y gain  Pat Z In dry carcase  46.09  17.81  20.81  39.12  38.63  29.21  31.73  26.06  24.03  22.26  29.34  24.33  * 1.78  1 4 5 7 11 6 8 12 9 10 3 2  Average d e l l y gain  T o t a l carcass ash(g)  6.22  6.55  6.72  6.08.  6.20  6.69  6.30  6.69  6.44  6.49  6.13  6.47  ± 0.13  3 6 8 2 7 10 12 9 1 3 11 4  Average d a i l y gain  Aah Z In dry carcass  8.36  10.98  .11.02  8.68  8.99  10.19  9.67  10.71  10.36  10.41  9.50  10.10  ± 0.30  3 2 8 10 9 6 12 7 11 5 4 1 —-  Average d a l l y gain(-)  15.52  13.98  13.93  14.30  14.00  14.37  14.18  14.48  13.65  13.38  13.44  13.32  ±0.14  1 8 6 4 7 3 3 9  Average d a l l y galn(-).  O  Ash Z i n f a t free cercasa Proteln+fat+ash , Dry carcaaa wt.  11 10 2 12 F  97.61  96.39  96.83  Standard e r r o r o f treatment meens. Treatment means not uodaraeored by the  U.S.  l i n e are s i g n i f i c a n t l y d i f f e r e n t a t the 52 l e v e l of p r o b a b i l i t y  (Tukey,1953).  97.16  96.67  96.19  ±0.43  U.S.  M.S.  108 -  retention. 10  and  I t appeared t h a t the b e t t e r b a l a n c e d d i e t such as d i e t s 2, 3,  12  produce minimum f a t and maximum p r o t e i n r e t e n t i o n .  b a r l e y d i e t w h i c h was l i m i t i n g i n b o t h l y s i n e and t h r e o n i n e  The s o l e  produced  maximum f a t and minimum p r o t e i n r e t e n t i o n i n t h e c a r c a s s .  D i e t had a r a t h e r s m a l l s i g n i f i c a n t e f f e c t on c a r c a s s content.  However, t h e s e d i f f e r e n c e s c o u l d n o t be  Tukey s Test f  The  by  (1953).  r e s p o n s e o f r a t s t o l y s i n e and t h r e o n i n e  to be s i m i l a r t o t h a t o b t a i n e d w i t h t h e p i g . nine over  detected  t o t a l ash  0.10%  t o the 0.75%  the growth o f r a t s .  a d d i t i o n appeared  The i n c r e a s e o f added  threo-  l y s i n e b a r l e y d i e t d i d n o t f u r t h e r improve  Rats were o b s e r v e d t o improve growth by a d d i t i o n o f a  complete amino a c i d m i x t u r e .  However, i t i s d i f f i c u l t t o p r e d i c t whether  the a d d i t i o n o f some amino a c i d s t o t h e p i g d i e t w o u l d f u r t h e r improve t h e growth as shown by t h e r a t s , a s t h e b a r l e y d i e t has a c t u a l l y s a t i s f i e d t h e o t h e r e s s e n t i a l amino a c i d l y s i n e and t h r e o n i n e N.A.S.-N.R.C. (1972)  f o r the g r o w i n g - f i n i s h i n g p i g s  except f o r  as i n d i c a t e d by comparing a n a l y s i s f i g u r e s w i t h t h e feeding  standards.  - 109 -  C.  CONCLUSION  I t may be c o n c l u d e d t h a t d i e t s based on b a r l e y a l o n e w i t h adequate mineral  and v i t a m i n s u p p l e m e n t a t i o n do n o t s u p p o r t o p t i m a l growth and f e e d  conversion  efficiency i n rats.  The  PER,  p r o t e i n r e t e n t i o n and p r o t e i n  r e t a i n e d as p e r c e n t a g e o f p r o t e i n i n t a k e i n d i c a t e d t h a t such a d i e t i s o f poor p r o t e i n q u a l i t y .  U s i n g the above c r i t e r i a , p e r f o r m a n c e was improved  by l y s i n e s u p p l e m e n t a t i o n w i t h a f u r t h e r improvement produced l e v e l s o f t h r e o n i n e were added t o the d i e t .  Threonine  when graded  was  p r o b a b l y t h e second l i m i t i n g amino a c i d i n b a r l e y f o r t h e growing r a t .  A  0.75%  d i e t a r y l y s i n e was observed t o be adequate f o r normal  growth i n c o n j u n c t i o n w i t h nine i n the d i e t ) ,  as  0.10%  threonine  supplementation of  f u r t h e r improve p e r f o r m a n c e o f the r a t s . 0.20%  threonine  (either  0.75  addition 0.90%  (0.47%  total  threo-  dietary l y s i n e d i d not  The r e s u l t s a l s o i n d i c a t e d t h a t  s u p p l e m e n t a t i o n was r e q u i r e d i n t h i s b a r l e y - l y s i n e d i e t  or  0.90%  dietary lysine)  when an amino a c i d s m i x t u r e  t o maximize n i t r o g e n b a l a n c e  was added t o t h e d i e t .  The e v i d e n c e  obviously  showed t h a t a low q u a l i t y b a r l e y d i e t w i t h p r o p e r s u p p l e m e n t a t i o n o f l i m i t i n g amino  a c i d s can r e s u l t  barley-soybean d i e t . PER  i n performance e q u a l t o t h a t o b t a i n e d w i t h a  The b a r l e y - s o y b e a n d i e t s produced poor v a l u e s f o r  and p r o t e i n r e t a i n e d as p e r c e n t a g e o f p r o t e i n i n t a k e because o f e x c e s s  protein intake.  - 110  VII.  A.  a.  RAT  -  EXPERIMENT I I I  EXPERIMENTAL PROCEDURE  General The  e v i d e n c e of Rat E x p e r i m e n t I I  lysine barley diet)  and  diet with  0.20%  (0.57%  0.75%  t o t a l threonine i n  an amino a c i d m i x t u r e p r o v i d e d o p t i m a l growth e q u i v a l e n t  obtained with  a barley-soybean c o n t r o l d i e t .  o p t i m a l growth appeared to be mixture.  threonine  i n d i c a t e d that a  the  to  that  A requirement f o r a t t a i n i n g  the a d d i t i o n of the e s s e n t i a l amino a c i d  However, i t i s s t i l l p o s s i b l e t h a t the improvement may  have been  a t t a i n e d by a d d i t i o n o f o t h e r n i t r o g e n s o u r c e s i n s t e a d o f e s s e n t i a l amino acids.  Such an a d d i t i o n of n o n - s p e c i f i c  more d e s i r a b l e proteins  n i t r o g e n would be  economically  than the a d d i t i o n of amino a c i d s e i t h e r i n p u r e form o r  i n p r a c t i c a l pig feeding.  T h e r e f o r e the f o l l o w i n g e x p e r i m e n t  d e s i g n e d t o i n v e s t i g a t e the e f f e c t of s u p p l e m e n t a t i o n o f g l y c i n e as nitrogen  as was  a  s o u r c e on growth p e r f o r m a n c e , f e e d c o n v e r s i o n e f f i c i e n c y , p r o t e i n  u t i l i z a t i o n and  r e t e n t i o n of r a t s and  to compare g l y c i n e a d d i t i o n  with  a d d i t i o n of an amino a c i d m i x t u r e .  The treatment.  b.  experiment c o n s i s t e d  D u r a t i o n was  4  of  10  treatments w i t h  4  rats  per  weeks.  Animals A t o t a l of  average w e i g h t o f  44  88 g  a l b i n o male r a t s (Woodlyn/Wistar s t r a i n ) and  30 ± 1  days o f age  were employed.  with Four o f  - Ill  these were k i l l e d i n i t i a l l y  -  to o b t a i n a c o n t r o l measure of body  A l l o t h e r p r o c e d u r e s were e x a c t l y the same as i n the p r e v i o u s c.  experiment.  Diets Hie c o m p o s i t i o n  these d i e t were of  composition.  10  o f the d i e t i s shown i n T a b l e 1 4 . T h  t h e same as f o r Rat Experiment I .  e  preparation of  The e x p e r i m e n t c o n s i s t e d  t r e a t m e n t s as f o l l o w s : 1.  Barley only to supply  0.41%  total  lysine.  2.  Barley +  0.444%  L-lysine-HCl  to supply  0.75%  total  lysine.  3.  Barley +  0.637%  L-lysine-HCl  to supply  0.90%  total  lysine.  0.10%  threonine.  f 4.  Diet 2 +  5.  D i e t 4 + amino a c i d m i x t u r e .  6.  Diet 4 + glycine.  7.  Diet 2 +  8.  D i e t 7 + amino a c i d  9.  Diet 7 + glycine.  10.  0.20%  threonine. mixture.  Barley-soybean to supply  The c o m p o s i t i o n i n Rat E x p e r i m e n t I I .  0.75%  lysine.  of., the amino a c i d m i x t u r e was the same as t h a t  Management  Same as R a t E x p e r i m e n t I Records  Same as R a t Experiment I Chemical A n a l y s i s  Same as R a t E x p e r i m e n t I Calculations Same as Rat E x p e r i m e n t I  Statistical  Analysis  Same as R a t E x p e r i m e n t I  - 113 -  T a b l e 14.  P e r c e n t a g e c o m p o s i t i o n o f d i e t s used i n Rat Experiment I I I ( a i r d r y b a s i s )  D i e t No. Ingredients 1 Barley  2  4  3  5  6  7  8  9  10  96.82 96.38 96.19 96.28 94.53 94.93 96.18 94.43 94.83 81.34  Soybean meal  -  L - l y s i n e HC1*  -  L-threonine*  -  -  -  L-Arginine*  -  -  L-tryptophan*  -  L-histidine*  -  -  -  -  -  -  -  -  0.444 0.637 0.444 0.444 0.444 0.444 0.444 0.444  15.60  -  0.10  0.10  0.10  0.20  0.20  0.20  -  •-  -  0.20  -  -  0.20  -  -  -  -  -  0.05  -  -  0.05  -  -  -  -  -  0.20  -  L-leucine*  -  -  -  -  0.20  -  0.20  L-isoleucine*  -  -  -  -  0.20  -  -  -  0.20  -  -  L-phenylalanine*  -  -  -  -  0.30  -  -  0.30  -  -  DL-methionine*  -  -  -  -  0.20  -  -  0.20  -  -  L-valine*  -  -  -  -  0.10  -  -  0.10  -  -  L-Glutamic a c i d *  -  -  -  0.30  -  -  0.30  -  -  L-Glycine*  -  -  -  -  -  1.355  -  -  1.355  -  Trace m i n e r a l and v i t a m i n premix  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  Defluorinated rock phosphate  1.64  1.64  1.64  1.64  1.64  1.64  1.64  1.64  1.64  1.49  Limestone  0.54  0.54  0.54  0.54  0.54  0.54  0.54  0.54  0.54  0.57  Iodized  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  0.50  salt  0.20  -  The c o m p o s i t i o n o f t r a c e m i n e r a l and v i t a m i n premix was t h e same as t h a t o f used i n P i g E x p e r i m e n t s I  and  II.  * The L - l y s i n e HC1 was f e e d grade and was 98% p u r e , c o n t a i n i n g 78% L-lysine. H i e L - t h r e o n i n e was pure and DL-methionine was 98% p u r e . A l l were produced by the A j i n o m o t o Co., Japan.  - 114 T a b l e 15.  Content o f e s s e n t i a l amino a c i d s o f each d i e t f o r Rat Experiment I I I (g  amino a c i d / l O O g  mixed  feed)  on a i r d r y b a s i s .  D i e t No. Amino A c i d  1  2  3  4  5  6  7  Arginine  0 .45  0,.45  0,.45  0..45  0 .64  0.,45  0 .45  0 .64. 0 .45  0 .82  Histidine  0 .21  0..21  0,.21  0,.21  0 .40  0.,21  0 .21  0 .40  0 .21  0 .40  Isoleucine  0 .40  0,.40  0,.40  0..40  0 .59  0,.40  0 .40  0 .59  0 .40  0 .58  Leucine  0 .73  0..73  0,.73  0,.73  0 .91  0,.73  0 .73  0 .91  0 .73  1 .18  Lysine  0 .41  0,.75  0,.90  0..75  0 .75  0..75  0 .75  0 .75  0 .75  0 .75  Methionine  0 .17  0..17  0,.17  0,.17  0 .36  0,.17  0 .17  0 .36  0 .17  0 .24  0 .20  0..20  0,.20  0,.20  0 .20  0..20  0 .20  0 .20  0 .20  0 .27  Phenylalanine  0 .53  0,.53  0..53  0,.53  0 .82  0,.53  0 .53  0 .82  0 .53  0 .80  (Tyrosine)*  0 .28  0,.28  0,.28  0,.28  0 .28  0..28  0 .28  0 .28  0 .28  0 .48  Threonine  0 .37  0,.37  0,.37  0,.47  0 .47  0..47  0 .57  0 .'57  0 .57  0 .57  Tryptophan  0 .11  0 .11  0 .11  0,.11  0 .16  0 .11  0 .11  0 .16  0 .11  0 .19  Valine  0 .68  0..68  0..68  0.,68  0 .76  0..68  0 .68  0 .76  0 .68  0 .86  G l u t a m i c a c i d * * 2 .36  2.,36  2..36  2..36  2 .60  2,,36  2 .36  2 .60  2 .36  2 .97  Glycine**  0,,42  0..42  0.,42  0 .41  1..77  0 .42  0 .41  1 .77  0 .56  (Cystine)*  Dry m a t t e r content %  0 .42  8  9  10  90 .14 89..13 89..69 90..12 90 .00 89.,93 89 .94 89 .57 89 .85 90 .45  Crude p r o t e i n % (N x 6.25) 10 .58 11.,17 11..39 11..15 12 .74 12..86 11 .24 12 .89 12 .91 17 .40  * Semi-essential  amino a c i d  ** N o n - e s s e n t i a l amino a c i d  - 115 -  B.  The while  r e s u l t s of  the carcass  The obtained  RESULTS AND DISCUSSION  ADG,  FCE  and  PER  a r e p r e s e n t e d i n T a b l e 16  a n a l y s i s d a t a a r e summarized i n T a b l e 17  r a t s f e d w i t h d i e t s the same as t h o s e i n R a t E x p e r i m e n t I I  b a s i c a l l y s i m i l a r r e s u l t s i n terms o f  protein analysis values.  This  ADG,  FCE,  threonine  The e v i d e n c e  as t h e second l i m i t i n g amino a c i d i n b a r l e y .  r a t s ' p e r f o r m a n c e on t h e 0.75% s i g n i f i c a n t l y , further confirming 0.75%  and c a r c a s s  f u r t h e r confirmed the importance of  a d d i t i o n t o b a r l e y - l y s i n e t o improve the p r o t e i n q u a l i t y . also confirmed threonine  PER  and  0.90%  The  l y s i n e diets d i d not d i f f e r  the previous experimental r e s u l t s that  l y s i n e i s adequate f o r t h e growing r a t . W i t h t h e same l e v e l o f  l y s i n e i n the d i e t s , a d d i t i o n of s i g n i f i c a n t l y b e t t e r than were r e v e r s e d  0.20 %  0.10%  threonine  threonine  was s l i g h t l y b u t non-  addition.  and s i g n i f i c a n t l y i n f a v o r of t h e 0.20%  d i e t when f u r t h e r amino a c i d m i x t u r e s were added. T h i s  However, t h e r e s u l t s threonine observation  added was i n  agreement w i t h R a t E x p e r i m e n t I I .  Replacement o f t h e amino a c i d m i x t u r e w i t h g l y c i n e on an i s o n i t r o g e nous b a s i s f a i l e d t o show t h e same performance i n a l l measured c r i t e r i a c a t i n g t h a t the improved p e r f o r m a n c e i n d i e t 8 was n o t due t o n i t r o g e n  indilevel  p e r s e b u t r a t h e r due t o t h e p r o p e r b a l a n c e o f e s s e n t i a l amino a c i d s i n t h e diet.  As a m a t t e r o f f a c t , g l y c i n e a d d i t i o n d e p r e s s e d t h e r a t p e r f o r m a n c e .  T h i s s u g g e s t s t h a t t h e a d d i t i o n o f g l y c i n e a t t h e s e l e v e l s c r e a t s an imbalance.  Rama Rao e t a l .  (1960) r e p o r t e d  that g l y c i n e might depress  Table 16.  1 Veek  Barley • only (Basal)  E f f e c t of emlno a c i d aupplenentatton  2 B + ly.(0.75W  2.77  3.21  3.28  3.93  3.04  3.68  2.59  3.49  3 B + lys(0.90I)  3.54  4 B +' lys(0.75J> +0.10*thr  4.35  of low p r o t e i n b a r l e y on ayerat* d a l l y gain, feed  5 B + lye (0.732) +O.10Zthr+ amino acid mixture .  6 B + lya (0.751) +0.10Ithr+ glycine  7 B + lys(0.751) +0.201thr  ' eonveralon e f f i c i e n c y and protein e f f i c i e n c y r a t i o of r a t a .  e B + lys(0.752) +0.202thr+ 'amino acid mixture  9 B + lys(0.751)+ 0.20Ithr + glycine  10 Barley-soy (control)  SE*  Result o.t significance test**  • Significant eovsrlablea  4.82  4.66  3.93  i 0.17  10 8 5 6 9 7 4 3 2 1 "  I n i t i a l velght(-) Average feed intake  5.22  4.11  3.73  ± 0.23  10 8 5 9 4 7 6 5 2 1  Average feed  5.68  t 0.21  8 10 9 5 4 6 7 3 2 1 •  I n i t i a l velght(-) Average feed Intake  Intake  Daily  Caln(g)  Overall period  Converalon Efficiency  (  3  gale Overall period  3.28  4.47  4.06  4.62  3.89  5.01  4.40  4.69  4.70  3.47  4.30  4.93  4.23  4.71  t 0.30  8 3 10 9 4 6 7 2 3 1 •—^Z^^ZZI^I™1__  I n i t i a l velght(-) Average feed intake  3.93  4.42  4.81  4.41  3.19  * 0.11  10 8 5 9 4 6 7 3 2 1 —  I n i t i a l uelght(-) Average feed lnteke  2.23  x 0.16  1_2 3 4 7 5 9 6 8 ——  I n i t i a l velght Average feed lntakef,-)  2.78  t 0.18  12  1_2376439 ZZZ^^L  3.47  2.47  4.05  3.48  3.43  3.32  3.68  2.68  2.97  2.79  t 0.17  3.74  4.61  4.63  3.73  J.18  3.77  4.41  2.63  3.56  3.60  i 0.36  4.58  3.97  3.78  3.37  3.12  3.33  3.47  2.88  3.22  2.94  1 0.08  Initial velght Protein Efficiency Ratio  92  2.04  2.22  2.37  Standard e r r o r of treatment means. Treatment means not underscored by the seme l i n e are s i g n i f i c a n t l y d i f f e r e n t at the 5X l e v e l of p r o b a b i l i t y (Tukey, 1953).  2.02  x  10  6 3 4 7 9 3 10 8  10 8  . N.S. 1 2 J 7 * ( ! ! 10 8 ~—  2.33  10.06  8 4 7 5 9 3 6 2 1 10  8.S.  I n i t i a l weight Average feed intake(-) I n i t i a l weight Averege feed intake(-) I n i t i a l velght Averege feed lotake(-)  ON  Table 17.  Effect of amino and uuppU'tauntntlon of low protein bnrley on carcaaa char net 4 r l a t l c e of rata  • 1  2  3  4  36.39  42.81  24.60  25.00  23.12  24.03  26.58  23.61  42.29  32.90  49.01  44.23  50.76  55.45  47.58  49.65  60.34  59.04  53.27  38.53  78.13  79.88  79.48  80.09  80.63  80.88  34.33  28.83  26.42  13.28  16.68  49.86  41.63  38.23  24.43  5.84  6.02  8.23  6.81  7.49  8.JO  8.95  11.03  10.31  9.99  10.18  10.87  14.95  14.28  14.49  14.60  13.84  14.31  14.12  96.18  96.42  96.19  96.01  93.96  97.20  96.80  33.91  34.33  37.38  P r o t e i n retention during 29 daye on t r i a l (g)-  18.39  21.12  21.55  Protein r e t a l n e d j Protelo Intake  33.84  41.63  P r o t e i n Z l o dry carcase  40.39  P r o t e i n Z In f a t free carcase T o t a l carcaas  Aeh Z In f a t free carcaaa Proteln+fat+Ash Dry carcass wt.  10  39.33  31.19  Ash Z In dry carcaaa  9  36.80  Toc.1 c l r e u i p r o t e i n (*,)  ash (g)  8  35.90  0 + lye(0.75Z) +0.10Zthr  T o t a l carcaaa  7  37.76  B 4lys(0.90Z)  Fat Z l a dry carcess  6  8 + ly.i(0.75Z> +0.20Ztlir  B + lys(0.75Z)  f a t (g)  5  B + lys(0.75Z) +0.102thr+ glycine  Barley only (Basal)  B + lys(0.75Z) +0.10Zthr+ anlno s c l d mixture  B + lys(0.75Z) *O.20Zthr+ amino acid mixture  B T lys(0.75Z) •K).20Zthr+ glycine  Barley-soy (control)  SE«  Result o f s i g n i f i c a n c e test  Slcntftcant covariable  • t 0.68  10 8  5 4 7 9 6 3 2 1  Average d a l l y gain  30.06  t 0.68  10 8  5 4 7 9 6 3 2 1  Average d a i l y gain  45.97  42.71  t 1.23  8 4 7 5 9 6 3 10 2 1  Average d e l l y gain  63.06  59.47  71.88  t 1.67  10 8 4 9 5 7 6 3 2 1  Averege d a l l y galn(-)  81.45  81.78  81.08  82.39  t 0.78  20.41  17.62  13.46  16.58  3.40  t 1.38  1 2 3 6 7 5 9 4 8 10  Average d a l l y gain  25.76  31.26  27.94  21.93  26.81  10.77  i 1.69  1 1 3 6 7 9 3 4 8 10  Average d a l l y gain  6.45  6.39  6.37  6.63  6.34  7.18  0.15  10  4 8 5 6 7 9 3 2 1  Average d e l l y gein  10.33  12.31  + 0.28  8 9 5 7 6 3 2 1  Average d a i l y gain  15.89  14.12  14.07  0.23  R.S.  N.S.  96.66  96.47  96.73  + 0.33  N.S.  N.S.  Standard error of treatment aean. »t underacored by the same l i n e are a l g n l f l c a n t l y different at the 51 l e v e l of probability  (Tukey, 1933).  N.S.  10 4  N.S.  - 118 -  growth when g i v e n i n l a r g e amounts.  S i n c e g l y c i n e has been r e p o r t e d t o be l e s s e f f e c t i v e when used as a n i t r o g e n s o u r c e 1949),  than ammonium s a l t s and L - g l u t a m i c a c i d (Rose e_t a l . ,  i t i s s t i l l p o s s i b l e t h a t r a t growth coulb be improved by u s i n g  e i t h e r ammonium s a l t s o r g l u t a m i c a c i d t o i n c r e a s e t h e d i e t a r y n i t r o g e n level.  C a r c a s s p r o t e i n r e t e n t i o n showed t h e 0.75% with  lysine barley diet  0.20% added t h r e o n i n e , and an amino a c i d m i x t u r e n o t t o be s i g n i f i -  c a n t l y d i f f e r e n t from t h e b a r l e y - s o y b e a n r e s u l t s o b t a i n e d i n R a t Experiment I I . f o r p r o t e i n r e t a i n e d as a p e r c e n t a g e  control.  T h i s was s i m i l a r t o the  The former d i e t had t h e b e s t v a l u e  of p r o t e i n i n t a k e .  The a d d i t i o n o f g l y c i n e d i d n o t improved t h e c a r c a s s p r o t e i n r e t e n t i o n and t h e v a l u e f o r p r o t e i n r e t a i n e d as a p e r c e n t a g e intake.  I t a l s o appeared t o depress  the v a l u e s o f t h e above c r i t e r i a when  compared w i t h v a l u e s o b t a i n e d w i t h s i m i l a r d i e t s w i t h o u t  The  of p r o t e i n  carcass data f u r t h e r confirmed  glycine.  t h a t g l y c i n e n i t r o g e n cannot  r e p l a c e t h e n i t r o g e n o f an amino a c i d m i x t u r e f o r o p t i m a l r a t growth.  The  t o t a l c a r c a s s f a t c o n t e n t produced on t h e g l y c i n e - a d d e d d i e t s was h i g h e r than t h a t produced on t h e c o r r e s p o n d i n g amino a c i d supplemented d i e t s , s u p p o r t i n g t h e f a c t t h a t imbalanced balanced  diets.  d i e t s tend t o d e p o s i t e more f a t than  - 119 -  C.  CONCLUSION  Experiment I I I f u r t h e r i n d i c a t e d that f o r t h e growing r a t .  0.75%  l y s i n e was adequate  The b a r l e y - l y s i n e d i e t c o n t a i n i n g  0.75%  showed an improvement i n average d a i l y g a i n , f e e d c o n v e r s i o n n i t r o g e n r e t e n t i o n and  nitrogen retained/nitrogen intake  l e v e l s o f t h r e o n i n e were added. mixtures  t o t h e 0.20%  lysine  e f f i c i e n c y and  when graded  "The s u p p l e m e n t a t i o n w i t h amino a c i d  t h r e o n i n e - a d d e d b a r l e y - l y s i n e d i e t s gave r a t  performance e q u i v a l e n t t o t h a t o b t a i n e d w i t h t h e b a r l e y - s o y b e a n c o n t r o l diet.  This confirmed  the r e s u l t  o f Rat E x p e r i m e n t I I .  When g l y c i n e was used as a n i t r o g e n s o u r c e , f a c t o r i l y r e p l a c e t h e amino a c i d m i x t u r e l y s i n e - threonine  diet.  The d e p r e s s i o n  i t f a i l e d to s a t i s -  as a supplement t o t h e b a r l e y -  o f r a t growth and n i t r o g e n r e t e n t i o n  i n d i c a t e d t h a t g l y c i n e a t t h i s l e v e l cannot b e u l t i l i z e d e f f e c t i v e l y as a n i t r o g e n s o u r c e f o r t h e growing r a t .  Amino  a c i d ' i m b a l a n c e ' might have  been c r e a t e d when t h i s l e v e l o f g l y c i n e was added.  I t i s possible that e i t h e r  s u p p l e m e n t a t i o n o f one o r more o t h e r e s s e n t i a l amino a c i d s i n s t e a d o f t h i s t o t a l amino a c i d s m i x t u r e  or r a i s i n g t h e t o t a l n i t r o g e n l e v e l w i t h  source o f n i t r o g e n could give b e t t e r performance. i n v e s t i g a t e d i n t h i s experiment.  another  T h i s , however, was n o t  - 120 -  VIII.  GENERAL CONCLUSIONS  These e x p e r i m e n t s i n t h e p i g s and t h e r a t s have shown t h r e o n i n e t o b e t h e second l i m i t i n g amino a c i d i n b a r l e y , w i t h The  l y s i n e being the f i r s t .  t r e n d showed t h a t t h e a d d i t i o n o f graded l e v e l s o f L - t h r e o n i n e t o t h e  b a r l e y - l y s i n e d i e t (0.75% t o t a l l y s i n e ) p r o g r e s s i v e l y  improved t h e r a t e o f  growth, f e e d c o n v e r s i o n . e f f i c i e n c y , c a r c a s s q u a l i t y and n i t r o g e n for  the growing-finsihing  addition at a l e v e l of  p i g s t o a l e v e l o f 0.10% t h r e o n i n e . 0.10%  retention  Threonine  t o t h e d i e t (0.47% t o t a l t h r e o n i n e ) produced  the b e s t mean d a l l y g a i n , f e e d c o n v e r s i o n e f f i c i e n c y , eye muscle i n d e x and eye m u s c l e a r e a .  F u r t h e r a d d i t i o n o f t h r e o n i n e and t h r e o n i n e p l u s m e t h i o n i n e  d i d not. improve t h e above c r i t e r i a .  However, a l l amino a c i d supplemented  d i e t s gave growth r a t e s w h i c h were i n f e r i o r t o t h a t o b t a i n e d w i t h  t h e soybean  c o n t r o l d i e t p r i o r 45 Kg l i v e w e i g h t b u t n o t s i g n i f i c a n t l y d i f f e r e n t o v e r 45 Kg  liveweight.  The n i t r o g e n b a l a n c e s t u d y showed t h a t  a d d i t i o n gave n i t r o g e n  0.15%  threonine  r e t e n t i o n i n s i g n i f i c a n t l y d i f f e r e n t from o t h e r  t h r e o n i n e added d i e t s and from t h e c o n t r o l d i e t a l t h o u g h t h e c o n t r o l gave g r e a t e r n i t r o g e n  retention.  still  The b a r l e y - l y s i n e d i e t w i t h no t h r e o n i n e  a d d i t i o n gave s i g n i f i c a n t l y p o o r e r p e r f o r m a n c e i n growht r a t e , f e e d c o n v e r s i o n e f f i c i e n c y , c a r c a s s q u a l i t y and n i t r o g e n  r e t e n t i o n than t h e t h r e o n i n e  supplemented d i e t s  The o v e r a l l  the p i g e x p e r i m e n t s  and t h e c o n t r o l  diet.  s u g g e s t e d t h a t 0.10%  t h r e o n i n e added t o an 0.75%  l y s i n e - b a r l e y d i e t was comparable t o the c o n t r o l d i e t a f t e r weight.  However, a s l i g h t i n c r e a s e  r e s u l t s of  45 Kg  live-  i n t h e t o t a l l y s i n e and t h r e o n i n e  l e v e l s beyond 0.75% and 0.47%, r e s p e c t i v e l y , o r p r o v i s i o n o f a d d i t i o n a l  - 121 -  n i t r o g e n may b e a b l e t o r e d u c e t h e d i f f e r e n c e between t h e b a r l e y - a m i n o and b a r l e y - s o y b e a n meal d i e t s .  The r a t e x p e r i m e n t s the growing  acid  More work i s needed t o c l a r i f y t h i s p o i n t .  showed t h a t  0.75%  l y s i n e was adequate f o r  r a t s i n c e no s i g n i f i c a n t improvement was o b t a i n e d by f u r t h e r  addition of lysine  ( t o 0.90%  total lysine).  S i m i l a r to the r e s u l t s of  the p i g e x p e r i m e n t ,  the mean d a i l y g a i n , f e e d c o n v e r s i o n e f f i c i e n c y , p r o t e i n  e f f i c i e n c y r a t i o and n i t r o g e n r e t e n t i o n improved p r o g r e s s i v e l y w i t h t h e a d d i t i o n o f graded t h r e o n i n e l e v e l s . t o t a l threonine) growth.  The  0.10%  added t h r e o n i n e  (0.47%  a p p a r e n t l y p r o v i d e d an a d e q u a t e l y b a l a n c e d d i e t f o r r a t  However, 0.20% t h r e o n i n e had t o be added t o t h e d i e t  (0.57%  t h r e o n i n e ) when t h e d i e t was f u r t h e r supplemented w i t h a p u r i f i e d  total  essential  amino a c i d m i x t u r e i n o r d e r t o o b t a i n optimum r a t performance e q u i v a l e n t t o t h a t o b t a i n e d on t h e b a r l e y - s o y b e a n  diet.  G l y c i n e c o u l d n o t be used as t h e  n i t r o g e n s o u r c e t o r e p l a c e t h e amino a c i d m i x t u r e .  The e v i d e n c e o f t h e p r e s e n t s t u d y s t r o n g l y i n d i c a t e s t h a t p u r i f i e d amino a c i d s a r e as e f f e c t i v e as n a t u r a l p r o t e i n c o n c e n t r a t e s when added t o b a r l e y f o r t h e f i n i s h i n g p i g and t h e growing r a t .  F i n e adjustment o f t h e  b a l a n c e among amino a c i d s , e s p e c i a l l y between t h e f i r s t and s e c o n d l i m i t i n g amino a c i d s i s needed t o a c h i e v e o p t i m a l growth.  - 122  IX.  -  LITERATURE CITED  A b e r n a t h y , R.P., S e w e l l , R.F. and T a r p l e y , R.L. 1958. Interrelationships of p r o t e i n , l y s i n e and energy i n d i e t s f o r growing swine. J . Anim. S c i . 17: 635. A d i b i , S.A., Seymour, G.J. and Menden, E. 1967. The k i n e t i c s of amino a c i d a b s o r p t i o n and a l t e r a t i o n o f plasma c o m p o s i t i o n of f r e e amino a c i d s a f t e r i n t e s t i n a l p e r f u s i o n of amino a c i d m i x t u r e s . Am. J . C l i n . N u t r . 20: 24. A.R.C.  1967. The N u t r i e n t Requirements of Farm L i v e s t o c k No. 3. Pigs. T e c h n i c a l Review and Summaries. A g r i c u l t u r a l R e s e a r c h C o u n c i l , London.  A l m q u i s t , N.J. 1972. P r o t e i n s and Amino A c i d s i n A n i m a l N u t r i t i o n . S.B. P e n i c k & Co., A g r i b i s t i c s - N u t r i t i o n a u n i t of CPC Internat i o n a l Inc. New York. 5 t h E d i t i o n . A.O.A.C.  1965. O f f i c i a l Methods o f A n a l y s i s (10th E d . ) . Association O f f i c i a l A g r i c u l t u r a l C h e m i s t s . Washington, D.C.  of  A n d e r s o n , G.H. and Bowland, J.P. 1967. L y s i n e and f a t s u p p l e m e n t a t i o n of w e a n l i n g p i g d i e t s . Can. J . of Anim. S c i . 47: 47 A s h t o n , G.C., K a s t e l i c , J . , A r c k e r , D.C, J e n s e n , A.H., Maddock, H.H., K l i n e , E.A. and C a r t r o n , D.V. 1955. Different protein levels w i t h and w i t h o u t a n t i b i o t i c s f o r g r o w i n g - f i n i s h i n g swine : e f f e c t on c a r c a s s l e a n e s s . J . Anim. S c i . 14: 82. B a l d i n i , J.T., M a r v e l , J.P. and Rosenberg, H.R. 1957. The e f f e c t of the p r o d u c t i v e energy l e v e l of the d i e t on the m e t h i o n i n e r e q u i r e m e n t of the p o u l t . P o u l t r y S c i . 36: 1037. B a l d i n i , J.T. and Rosenberg H.R. 1955. The e f f e c t o f p r o d u c t i v e energy l e v e l o f the d i e t on the m e t h i o n i n e r e q u i r e m e n t of the c h i c k . P o u l t r y S c i . 34: 1301. B a l d i n i , J.T. and Rosenberg, H.R. 1957. The e f f e c t o f c a l o r i e s o u r c e i n a c h i c k d i e t on growth, f e e d u t i l i z a t i o n , and body c o m p o s i t i o n . P o u l t r y S c i . 36: 432. B a y l e y , H.S. and Summers, J.D. 1968. E f f e c t of p r o t e i n l e v e l and l y s i n e and m e t h i o n i n e s u p p l e m e n t a t i o n on the performance of g r o w i n g p i g s : Response of d i f f e r e n t sexs and s t r a i n s o f p i g s . Can. J . Anim. S c i . 48: 181.  - 123 -  Beames, R.M., D a n i e l s , L . J . and S e w e l l , J.O. 1968. The t o t a l r e p l a c e m e n t of p r o t e i n supplements by s y n t h e t i c l y s i n e i n r a t i o n s based on sorghum g r a i n f o r p i g s over 45 Kg l i v e w e i g h t . P r o c . A u s t . Soc. Anim. P r o d . 7: 391. Beames, R.M. and Pepper, P.M. 1969. The p a r t i a l replacement of soybean meal amino a c i d i n p i g r a t i o n s based on wheat and sorghum. A u s t . J . Exp. A g r . Anim. Husb. 9: 400. B e c k e r , D.E. 1958. The Feed-bag Red Book Buyer's Guide. U.S.A., E d i t o r i a l S e r v i c e s Co. pp. 157. B e c k e r , D.E. 1959. B a l a n c i n g Swine R a t i o n s . C o l l . of A g r i . C i r c . 811.  Milwaukee, Wis.,  U n i v e r s i t y of I l l i n o i s .  B e c k e r , D.E., J e n s e n , A.H. and Harmon, B.G. 1963. B a l a n c i n g Swine R a t i o n s . U n i v e r s i t y of I l l i n o i s . C o l l . o f A g r . C i r . 866. B e c k e r , D.E., J e n s e n , A.H. and Harmon, B.G. 111. A g r . Exp. S t a . C i r . 866.  1966.  B a l a n c i n g Swine R a t i o n s .  B e c k e r , D.E., A.H. J e n s e n , S.W. T e r r i l l , l . D . Smith and H.W. N o r t o n . 1957. The i s o l e u c i n e r e q u i r e m e n t of w e a n l i n g swine f e d two p r o t e i n levels. J . Anim. S c i . 16: 26. B e c k e r , D.E., Adams, C R . , T e r r i l l , S.W. and Meade, K . J . 1955b. The m e t h i o n i n e - c y s t i n e need o f t h e young p i g . J . Anim. S c i . 14: 1086. B e c k e r , D.E., L a s s i t e i , J.W., T e r r i l l , S.W. and N o r t o n , H.W. 1954b. L e v e l s o f p r o t e i n i n p r a c t i c a l r a t i o n s f o r t h e p i g . J . Anim. S c i . 13: 611. B e c k e r , D.E., N o t z o l t , R.A., J e s e n , A.N., T e r r i l l , S.W. and N o r t o n , H.W. 1955a. The t r y p t o p h a n r e q u i r e m e n t o f the young p i g . J . Anim. Sci. 14: 664. B e c k e r , D.E., U l l r e y , D.E. and T e r r i l l , S.W. 1954a. P r o t e i n and amino a c i d i n t a k e s f o r optimum growth r a t e i n t h e young p i g . J . Anim. S c i . 13: 346. B e c k e r , M. and H a r n i s c h , S. 1958. Recent s t u d i e s on the s i g n i f i c a n c e and e x a c t n e s s o f n i t r o g e n b a l a n c e s i n m e t a b o l i s m t r i a l s on l i v i n g a n i m a l s . 1. S t u d i e s on the c o n t r o l o f a n a l y t i c a l p r o c e d u r e s , e s p e c i a l l y n i t r o g e n a n a l y s e s . A r c h . T i e r e r n a h r u n g 8: 309. Beeson, W.M., J a c k s o n , H.D. and M e r t z , E.T. 1953. Q u a n t i t a t i v e t h r e o n i n e r e q u i r e m e n t o f the w e a n l i n g p i g . J : Anim. S c i . 12: 870.  - 124 -  Beeson, W.M., M e r t z , E.T. ment o f swine.  and S h e l t o n , D.C. 1948. The amino a c i d 1. Tryptophan. S c i e n c e 107: 599.  require-  Beeson, W.M., M e r t z , E.T. and S h e l t o n , D.C. 1949. E f f e c t of t r y p t o p h a n d e f i c i e n c y i n the p i g . J . Anim. S c i . 8: 532. B e l l , J.M.  1965. N u t r i e n t r e q u i r e m e n t o f Canadian Y o r k s h i r e swine. V. A s t u d y of the l y s i n e and p r o t e i n r e q u i r e m e n t o f f i n i s h i n g p i g s w e i g h i n g from 100 to 200 pounds. Can. J . Anim. S c i . 45: 105.  B e l l , J.M.  and V o l d e n g , L.O. 1968. F u r t h e r o b s e r v a t i o n s on l y s i n e and p r o t e i n r e q u i r e m e n t s of 23 to 89 Kg p i g s . Can. J . Anim. S c i . 48: 251.  B e l l , J.M., W i l l i a m , H.H., L o o s l i , J.K. and Maynard, L.A. 1950. The e f f e c t o f m e t h i o n i n e s u p p l e m e n t a t i o n o f a soybean o i l meal p u r i f i e d r a t i o n f o r growing p i g s . J . N u t r i t i m . 40: 551. Benton, D.A., H a r p e r , A.E., S p i v e y , H.E. and E l v e h j e m , C.A. 1956. L e u c i n e , i s o l e u c i n e and v a l i n e r e l a t i o n s h i p i n the r a t . A r c h Biochem. B i o p h y s . 60: 147. Bergen, W.G. and P u r s e r , D.B. 1968. E f f e c t of f e e d i n g d i f f e r e n t p r o t e i n s o u r c e s on plasma and gut amino a c i d s i n the growing r a t . J . N u t r . 95: 333. B l a c k b u r n , S. 1968. Amino A c i d D e t e r m i n a t i o n . M a r c e l Dekker, I n c . , New York.  Methods and  Techniques.  B l a i r , R.,  Dent, J.B., E n g l i s h , P.R. and Raeburn, J.R. 1969a. P r o t e i n , l y s i n e and f e e d i n t a k e l e v e l e f f e c t s on p i g growth. 1. Main effects. J . A g r . S c i . 72: 379.  B l a i r , R.,  Dent, J.B., E n g l i s h , P.R. and Raeburn, J.R. 1969b. P r o t e i n , l y s i n e and f e e d i n t a k e e f f e c t s on p i g growth. 2. E f f e c t s on c a r c a s s c o m p o s i t i o n and q u a l i t y . J . A r g . S c i . 73: 395.  B l o c h , R.O., F r o s e t h , J.A. and Kromann, P.R. 1972. Energy and f e e d i n g v a l u e o f wheat and b a r l e y . J . Anim. S c i . 35: 211 ( A b s t r . ) . Boomgaard, J . and B a k e r , D.H. 1970. The l y s i n e r e q u i r e m e n t o f the c h i c k a t f i v e p r o t e i n l e v e l s . P o u l t r y S c i . 49: 1369. Boomgaard, J . and B a k e r , D.H. 1971. Tryptophan r e q u i r e m e n t o f growing c h i c k s as a f f e c t e d by d i e t a r y p r o t e i n l e v e l . J . Anim. S c i . 33: 595. Boomgaard, J . and B a k e r , D.H. 1973. Tryptophan r e q u i r e m e n t of growing p i g s a t t h r e e l e v e l s of d i e t a r y p r o t e i n . J . Anim. S c i . 36: 303.  - 125 -  B o o t h , V.H. 1971. P r o b l e m i n the d e t e r m i n a t i o n of F D N B - a v a i l a b l e l y s i n e . J . S c i . Fd. A g r i c . 22: 658. Bowland, J.P. 1962. A d d i t i o n of l y s i n e and/or a t r a n q u i l i z e r t o low p r o t e i n , soybean meal supplemented r a t i o n f o r growing bacon p i g s . J . Anim. S c i . 21: 852. Bowland, J.P. 1964. The r e l a t i o n s h i p of energy and p r o t e i n i n the d i e t on the growth and energy e f f i c i e n c y of young p i g s . S e m i n a i r e I n t e r n a t i o n a l Organise" p a r L ' l n s t i t u t N a t i o n a l De L a Recherche Agronomique. Bowland, J.P. and B e r g , R.T. 1959. I n f l u e n c e of s t r a i n and sex on t h e r e l a t i o n s h i p o f p r o t e i n t o energy i n the r a t i o n s o f g r o w i n g and f i n i s h i n g bacon p i g s . Can. J . Anim. S c i . 39: 102. Bowland, J.P. and G r i m s o n , R.E. 1969. L y s i n e and m e t h i o n i n e supplementat i o n o f swine and r a t d i e t s c o n t a i n i n g up t o t h r e e p e r c e n t u r e a . W i s s e n S c h a f t l i c h e Z e i t s c h r i f t der U n i v e r s i t a t R o s t o c k T e i l I I . p. 213. Bragg,-D.B., I v y , C.A. and Stephenson E.L. 1969. Methods f o r d e t e r m i n i n g — a m i n o a c i d a v a i l a b i l i t y of f e e d s . P o u l t r y S c i . 48: 2135. Braude, R. and E s n a o l a , M.A. 1973. M e t h i o n i n e p l u s c y s t i n e r e q u i r e m e n t of g r o w i n g p i g s p e r f o r m a n c e , N r e t e n t i o n and c a r c a s s c o m p o s i t i o n of g r o w i n g p i g s g i v e n s e m i - p u r i f i e d d i e t s supplemented w i t h graded l e v e l s of D L - m e t h i o n i n e . B r . J . N u t r . 30: 437. B r a u d e , R. and Lerman, P. 1970. P r o t e i n and l y s i n e l e v e l s i n p r a c t i c a l rations. J . A g r . S c i . 74: 575. B r a u d e , R., M i t c h e l l , K.G., M y r e s , A.W. and Newport, M.J. 1972. The r e p l a c e m e n t o f p r o t e i n c o n c e n t r a t e s by s y n t h e t i c l y s i n e i n t h e d i e t of g r o w i n g p i g s . B r . J . N u t r . 27: 169. B r a v o , F.O., Meade, R . J . , S t o c k l a n d , W.L. and N o r d s t r o m , J.W. 1970. R e e v a l u a t i o n o f the i s o l e u c i n e r e q u i r e m e n t o f t h e g r o w i n g p i g plasma f r e e i s o l e u c i n e as a r e s p o n s e c r i t e r i o n . J . Anim. S c i . 31: 1137. B r e e s a n i , R. 1971. Amino a c i d s u p p l e m e n t a t i o n of c e r e a l g r a i n f l o u r s tested i n children. I n Amino A c i d F o r t i f i c a t i o n o f P r o t e i n Foods. E d i t e d by N.S. Scrimshaw and A.M. A l t s c h u l . The MIT P r e s s . B r i n e g a r , M.J., L o o s l i , J.K., W i l l i a m s , H.H. and Maynard, L.A. 1949. L y s i n e r e q u i r e m e n t f o r growing p i g s . Fed. P r o c . 8: 379.  - 126 -  B r i n e g a r , M.J., W i l l i a m s , H.H., F e r r i s , F.E., L o o s l i , J.K. and Maynard, L.A. 1950a. The l y s i n e r e q u i r e m e n t f o r t h e growth of s w i n e . J . N u t r . 42: 129. B r i n e g a r , M.J., W i l l i a m s , H.H., F e r r i s , F.H., L o o s l i , J.K. and Maynard, L.A. 1950b. L y s i n e r e q u i r e m e n t f o r growing s w i n e . F e d . Am. S o c . Expt. B i o l . 9: 353. B r o o k s , C.C. and Thomas, H.R. 1959. Supplements t o peanut o i l m e a l p r o t e i n f o r growing f a t t e n i n g swine. " J . Anim. S c i . 18: 1119. Brown, H.W., Harmon, B.G,. .and J e n s e n , A..H. 1973a. The l y s i n e r e q u i r e m e n t o f the f i n i s h i n g p i g f o r maximum r a t e o f g a i n and f e e d e f f i c i e n c y . J . Anim. S c i . 37: 708. Brown, H.W., Harmon, B.G. and J e n s e n , A.H. 1973b. L y s i n e r e q u i r e m e n t o f the f i n i s h i n g p i g f o r maximum c a r c a s s l e a n n e s s . J . Anim. S c i . 37: 1159. Brown, H.W., Harmon, B.G. and J e n s e n , A.H. 1974. T o t a l s u l f u r c o n t a i n i n g amino a c i d s i s o l e u c i n e and t r y p t o p h a n r e q u i r e m e n t s o f t h e f i n i s h i n g p i g f o r maximum n i t r o g e n r e t e n t i o n . J . Anim. S c i . 38: 59. Broxra, J.A. and C l i n e , T.R. 1974. U r e a e x c r e t i o n i n the p i g : an i n d i c a t o r o f p r o t e i n q u a l i t y and amino a c i d r e q u i r e m e n t s . J . N u t r . 104: 542. Buck, S.F., H a r r i n g t o n , G. and Johnson, R.F. 1962. The p r e d i c t i o n o f l e a n p e r c e n t a g e o f p i g s o f b a c o n w e i g h t from c a r c a s s measurements. Anim. P r o d . 4: 25. B u j a r d , E., Handwerik, V. and Mauron, J . t i o n of l y s i n e i n heated milk. A g r i c . 18: 52.  1967. The d i f f e r e n t i a l d e t e r m i n a 1. I n v i t r o methods. J . S c i . F d .  C a h i l l y , Jr.,G.M., M i l l e r , R.F., K e l l y , R.F. and B r o o k s , C.C. 1963. E f f e c t o f v a r i o u s l e v e l s o f d i e t a r y l y s i n e on c e r t a i n b l o o d phenomena, muscle development, and m u s c l e - p r o t e i n b i o l o g i c a l v a l u e o f growing s w i n e . J . Anim. S c i . 22: 726. Canada Depqrtment o f A g r i c u l t u r e . 1968. Canada's new hog c a r c a s s v a l u a t i o n system. L i v e s t o c k D i v i s i o n , P r o d u c t i o n and M a k e t i n g B r a n c h , Ottawa, O n t a r i o . Cannon, P.R., S t e f f e e , C H . , F r a z i e r , L.E., Rawley, D.A. and S t e p t o , R.C 1947. The i n f l u e n c e o f time o f i n g e s t i o n o f e s s e n t i a l amino a c i d s upon u t i l i z a t i o n i n t i s s u e s y n t h e s i s . F e d e r a t i o n P r o c . 6: 390. Calhoun, W.K., Hepburn, F.N. and B r a d l e y , W.D. 1960. The a v a i l a b i l i t y o f l y s i n e i n wheat, f l o u r , b r e a d and g l u t e n . J . N u t r . 70: 337.  - 127  -  C a r l s o n , K.H. and B a y l e y , H.S. 1970. N i t r o g e n and amino a c i d s i n the f e c e s o f young p i g s r e c e i v i n g a p r o t e i n - f r e e d i e t and d i e t s c o n t a i n i n g graded l e v e l s o f soybean o i l meal o r c a s e i n . J . Nutr. 100: 1353. Carpenter, K.J. food.  1960. The e s t i m a t i o n o f a v a i l a b l e l y s i n e i n a n i m a l p r o t e i n Biochem. J . 77: 604.  C a r p e n t e r , K.J., McDonald, I . and M i l l e r , W.S. 1972. Protein quality of f e e d i n g - s t u f f s . 5. C o l l a b o r a t i v e s t u d i e s on the b i o l o g i c a l assay of a v a i l a b l e methionine using chicks. Br. J . Nutr. 27: 7. Change, R.E., Germann, A.F.O., Beeson, W.M. and M e r t z , E.T. 1958. Effect o f p r o t e i n l e v e l on the l y s i n e requirement o f w e a n l i n g p i g s . J . Anim. S c i . 17: 1161. Chung, A.S. 1973. Amino a c i d s u p p l e m e n t a t i o n o f Peace R i v e r b a r l e y f o r g r o w i n g - f i n i s h i n g p i g s . M.Sc. T h e s i s . University of B r i t i s h Columbia. Chung, A.S. and Beames, R.M. 19 72. Amino a c i d s u p p l e m e n t a t i o n o f rations. J . Anim. S c i . 35: 1103 ( A b s t r . ) .  swine  Chung, A.S. and Beames, R.M. 1974. L y s i n e , t h r e o n i n e , m e t h i o n i n e and i s o l e u c i n e s u p p l e m e n t a t i o n o f Peace R i v e r b a r l e y f o r growing p i g s . Can. J . Anim. S c i . ( i n p r e s s ) . C l a r k , A . J . , Hays, V.W., M c C a l l , J.T. and Speer, V.C. 1963. F r e e amino a c i d s i n the plasma and i n t e s t i n a l c o n t e n t s of baby p i g s d u r i n g digestion. J . Anim. S c i . 22: 1118 ( A b s t r . ) . C l a u s e n , H. e t . a l . 1959, 1960, 1961 and 1962. Experiments w i t h p i g s . Reports a t the annual meetings o f the N a t i o n a l P^esearch I n s t i t u t e o f A n i m a l Hunbandry, Copenhagen. Clawson,  A.J.  1967.  Influence  o f p r o t e i n l e v e l , , a m i n o a c i d r a t i o n and  c a l o r i c d e n s i t y o f the d i e t on feed i n t a k e J . Anim. S c i . 26: 328.  and performance  of p i g s .  Combs, G.E., Conness, R.G., B e r r y , T.H. and W a l l a c e , H.D. 1967. E f f e c t of raw and h e a t e d soybeans on g a i n , n u t r i e n t d i g e s t i b i l i t y , plasma amino a c i d s and o t h e r c o n s t i t u e n t s o f growing p i g s . J . Anim. S c i . 26: 1067. Cooke, R.,  Lodge, G.A. and Lewis, D. 1972a. I n f l u e n c e o f energy and p r o t e i n c o n c e n t r a t i o n i n the d i e t on the performance o f growing pigs. 1. Response to p r o t e i n i n t a k e on h i g h - e n e r g y d i e t . Anim. P r o d . 14: 35.  Cooke, R.,  Lodge, G.A. and L e w i s , D. 1972b. I n f l u e n c e o f energy and p r o t e i n c o n c e n t r a t i o n i n the d i e t on the performance of growing pigs. 3. Response to d i f f e r e n c e s i n l e v e l s o f b o t h energy and protein. Anim P r o d . 14: 219.  - 128 -  C o u l s o n , R.A. and Hernandez, T. 1970. P r o t e i n d i g e s t i o n and amino a c i d a b s o r p t i o n i n the cayman. J . N u t r . 100: 810. C u r t i n , L.V., Abraham, J.., W i l l i a m s , H.H. , L o o s l i , J.R. and Maynard, L.A. 1952b. The m e t h i o n i n e r e q u i r e m e n t f o r the growth o f swine. J . N u t r . 48: 499. C u r t i n , L.V., L o o s l i , J.K., W i l l i a m , J.P. and W i l l i a m s , H.H. 1952a. M e t h i o n i n e as a supplement t o soybean o i l meal f o r w e a n l i n g J . Anim. S c i . 11: 459.  pigs.  D a v i d s o n , R.M., Young, L.G. and Thomas, 0.0. 1962. E f f e c t of l y s i n e a d d i t i o n s to a b a r l e y , b a r l e y soybean meal r a t i o n f o r growing f a t t e n i n g swine. J . Anim. S c i . 21: 670 ( A b s t r . ) .  and  D e v i l a t , J . , Pond, W.G. and W a l k e r , E.F., J r . 1970. D i e t a r y amino a c i d b a l a n c e i n g r o w i n g - f i n i s h i n g p i g s : e f f e c t on plasma amino a c i d concentration. Nutr. Report I n t e r n a t i o n a l 2: 257. Delhumeau, G., V e l e z P r a t t , G. and G i t l e r , C. 1962. The a b s o r p t i o n o f amino a c i d m i x t u r e s from s m a l l i n t e s t i n e o f the r a t . I . E q u i m o l a r m i x t u r e s and those s i m u l a t i n g egg a l b u m i n , c a s e i n and z e i n . J . N u t r . 77: 52. D'Mello, J.P.F. 1973. Amino a c i d i n t e r a c t i o n s i n p o u l t r y 4 t h Europ. P o u l t . Conf., London, p.331.  nutrition.  D'Mello, J.P.F. 1974. Plasma c o n c e n t r a t i o n s and d i e t a r y r e q u i r e m e n t s o f l e u c i n e , i s o l e u c i n e and v a l i n e : S t u d i e s w i t h the young c h i c k . J . S c i . Fd. A g r i c . 25: 187. D ' M e l l o , J.P.F. and L e w i s , D. 1970a. Amino a c i d i n t e r a c t i o n i n c h i c k nutrition. 1. The i n t e r r e l a t i o n s h i p between l y s i n e and a r g i n i n e . B r . P o u l t . S c i . 11: 299. D ' M e l l o , J.P.F. and L e w i s , D. 1970b. Amino a c i d i n t e r a c t i o n i n c h i c k nutrition. 2. The i n t e r r e l a t i o n s h i p between l e u c i n e , i s o l e u c i n e and v a l i n e . B r . P o u l t . S c i . 11: 313. D ' M e l l o , J.P.F. and L e w i s , D. 1970c. Amino a c i d i n t e r a c t i o n i n c h i c k nutrition. 3. The i n t e r d e p e n d e n c e i n amino a c i d r e q u i r e m e n t s . • B r . P o u l t . S c i . 11: 367. E r i c s o n , L.E. 1961. A c r i t i c i s m o f the c a r c a s s a n a l y s i s p r o c e d u r e f o r the d e t e r m i n a t i o n o f amino a c i d r e q u i r e m e n t s . A c t a . P h y s i o l . Scand. 52: 90. Ericson,  L.E. , L a r s s o n , S. and Ostholm, C O . 1962. P r e l i m i n a r y s t u d i e s on the p r o t e i n v a l u e o f c e r e a l s f o r swine by l y s i n e s u p p l e m e n t a t i o n . A c t a . A g r . Scand. 12: 157.  - 129 -  Evans, R.E. 1958. N u t r i t i o n o f bacon p i g . X I X . The r e q u i r e m e n t o f t h e bacon p i g f o r c e r t a i n e s s e n t i a l amino a c i d s . J . Agric. S c i . Camb. 50: 230. Evans, R.E. 1959. The minimum amount o f w h i t e - f i s h meal r e q u i r e d t o supplement t h e p r o t e i n s i n some v e g e t a b l e p r o t e i n c o n c e n t r a t e s . J . A g r i c . S c i . Camb. 53: 230. Evans, R.E. 1960. The e f f e c t o f a d d i n g l y s i n e and m e t h i o n i n e t o t h e d i e t of p i g s k e p t on l o w - p r o t e i n v e g e t a b l e f o o d s . J . A g r i c . S c i . Camb. 54: 266. Evans, R.E. 1962. The i s o l e u c i n e r e q u i r e m e n t o f t h e w e a n l i n g J . A g r i c . S c i . Camb. 58: 413.  pigs.  Evans, R.E. 1963. The t h r e o n i n e r e q u i r e m e n t o f t h e w e a n l i n g p i g s . J . A g r i c . S c i . Camb. 60: 259. F i s h e r , H.  1965. F u r t h e r s t u d i e s on t h e l i m i t i n g amino a c i d s i n d i f f e r e n t l y p r o c e s s e d groundnut meal. J . S c i . F d . A g r i c . 16: 390.  F i n o t , P.A. 1973. Non-Enzymic B r o w i n g . I n ' P r o t e i n s i n human n u t r i t i o n ' . E d i t e d by P o r t e r , J.W.G. and R o l l s , B.A. Academic P r e s s , London and New Y o r k . p. 501. Firnney,  D.H. 1964. S t a t i s t i c a l Method i n B i o l o g i c a l A s s a y . by C h a r l e s G r i f f i n and Co. L t d . London.  2nd e d i t i o n  F l o r e n t i n o , R.F. and Peason, W.N. 1962. E f f e c t o f t h r e o n i n e i n d u c e d amino a c i d i m b a l a n c e on t h e e x c r e t i o n o f t r y p t o p l a n m e t a b o l i t e s by t h e r a t . J . N u t r . 78: 101. F o r b e s , R.M. and Rao, T. 1959. The e f f e c t o f age on t h e n e t r e q u i r e m e n t s o f n i t r o g e n , l y s i n e and t r y p t o p h a n b y w e l l - f e d r a t . A r c h . Biochem. B i o p h y s . 82: 348. F o r d , J . E . 1962. A m i c r o b i o l o g i c a l method f o r a s s e s s i n g t h e n u t r i t i o n a l value of proteins. 2. The measurement o f ' a v a i l a b l e ' m e t h i o n i n e , l e u c i n e , i s o l e u c i n e , a r g i n i n e , h i s t i d i n e , t r y p t o p h a n and v a l i n e . B r . J . N u t r . 16: 409. :  F o r d , J . E . 1960. A m i c r o b i o l o g i c a l method f o r a s s e s s i n g value of proteins. B r . J . N u t r . 14: 485.  the n u t r i t i o n a l  F r a p e , D.L., W o l f , K.L., W i l k i n s o n , J . and Cubb, L.G. 1968. M o d i f i c a t i o n to s h i n f i e l d m e t a b o l i s m c r a t e . J . I n s t . Anim. Tech. 19: 6 1 . F u l l e r , M.F. and Boyne, A.W. 1971. The e f f e c t s o f e n v i r o n m e n t a l temperat u r e on growth and m e t a b o l i s m o f p i g s g i v e n d i f f e r e n t amounts o f f o o d . 1. N i t r o g e n m e t a b o l i s m , growth and body c o m p o s i t i o n . B r i t . J . N u t r . 25: 259.  - 130 -  G a l l o , J.T. and Pond, VI.G. diets for pigs.  1968. Amino a c i d s u p p l e m e n t a t i o n to a l l - c o r n J . Anim. S c i . 27: 73.  Germann, A.F.O., M e r t z , E.T. and Beeson, W.M. 1958. Reevaluation of the L - l y s i n e r e q u i r e m e n t o f w e a n l i n g p i g . J . Anim. S c i . 17: 52. G i o v a n e t t i , P.M., S t o t h e r s , S.C. and P a r k e r , R.J. 1970. Coprophagy p r e v e n t i o n and a v a i l a b i l i t y o f amino a c i d s i n wheat f o r the growing r a t . Can. J . Anim. S c i . 50: 269. Grau, C.R.  and C a r r o l l , R.W. 1958. E v a l u a t i o n of P r o t e i n Q u a l i t y i n P r o c e s s e d P l a n t P r o t e i n F o o d s t u f f s , p. 153-189. A.M. A l t s c h u l ( E d i t o r ) . Academic P r e s s , New Y o r k .  Halm, J . and Le. C D . 1974. UBC MFAV. A n a l y s i s o f v a r i a n c e / c o v a r i a n c e . Computing C e n t r e . The U n i v e r s i t y o f B r i t i s h C o l u m b i a , Canada. H a r p e r , A.E. 1959. Advances i n our knowledge o f p r o t e i n and amino a c i d r e q u i r e m e n t s . Feb. P r o c . Supplement. No. 3, P a r t I I . 104. H a r p e r , A.E. 1961. Amino a c i d i m b a l a n c e , c h e m i c a l s c o r e and e f f i c i e n c y o f p r o t e i n u t i l i z a t i o n . Nat. Acad. S c i . - N a t . Res. Counc. Washington, D.C. P u b l . No. 843. p. 443-450. H a r p e r , A.E. 1964. Amino A c i d T o x i c i t i e s and Imbalances. I n Mammalian P r o t e i n M e t a b o l i s m . Academic P r e s s , New Y o r k . N.Y. H a r p e r , A.E., B e a t o n , D.A., W i n e j e , M.E. and E l v e h j e m , C.A. 1954. Leucinei s o l e u c i n e antagonism i n the r a t . A r c h . Biochem. B i o p h y s . 51: 523. H a r t s o o k , E.W. and M i t c h e l l , H.H. 1956. The e f f e c t o f age on the p r o t e i n and m e t h i o n i n e r e q u i r e m e n t s o f t h e r a t . J . N u t r . 60: 173. Henry, Y. and R£rat, A. 1970. E s t i m a t i o n du b e s o i n en t h r e o n i n e chez l e p o r e f e m a l l e e n t r e 20 e t 50 k g de p o i d s v i f . Journees de l a Recherche P o r c i n e en F r a n c e . P a r i s . INRA, p. 73. Henry, Y., R£rat, A. and Tomassone, B. 1971. L y s i n e r e q u i r e m e n t o f the g r o w i n g - f i n i s h i n g p i g . A p p l i c a t i o n o f the m u l t i v a r i a t e s t a t i s t i c a l a n a l y s i s . A n n a l e s de Z o o t e c h n i e 20: 521. H e t z e r , H.O., Harvey, W.R. and P e t e r s , W.H. 1963. G e n e t i c s . P r o c e e d i n g s of the 11th I n t e r n a t i o n a l Congress, The H a g i r e , The N e t h e l a n d s . 1: 268. H i n t z , H.F.  and l l e i t m a n , H. J r . 1967. Amino a c i d and v i t a m i n supplementat i o n t o b a r l e y - c o t t o n s e e d meal d i e t s f o r g r o w i n g - f i n i s h i n g swine. J . Anim. S c i . 26: 474.  - 131 -  H u g l i , T.E. and Moore, S . 1972. D e t e r m i n a t i o n o f t h e t r y p t o p h a n c o n t e n t of p r o t e i n s by i o n exchange chromatography o f a l k a l i n e h y d r o l y sates. J . B i o l . Chem. 247: 2828. J e n s e n , A.H., B e c k e r , D.E. and Harmon, B.G. 1965. N u t r i t i o n a l adequacy o f m i l o f o r t h e f i n i s h i n g p i g . J . Anim. S c i . 24: 398. J o n e s , A.S., Cadenhead, A. and L i v i n g s t o n e , R.M. 1968. V a r i a t i o n i n t h e c o m p o s i t i o n o f b a r l e y and i t s e f f e c t on t h e p e r f o r m a n c e o f p i g s . J. S c i . Fd. Agric. 19: 446. J o n e s , A.S., Hepburn, W.R., Cadenhead, A. and Boyne, A.W. 1962. The e f f e c t of v a r i a t i o n o f p r o t e i n q u a l i t y and p r o t e i n l e v e l i n d i e t s on t h e p e r f o r m a n c e o f young p i g s . Anim. P r o d . 4: 185. J o n e s , J.D. 1964 313.  Lysine-arginine  antagonism i n t h e c h i c k .  J . Nutr.  84:  J u r g e n s , M.H., Hudman, D.B., Adams, C H . and Peo, E.R., J r . 1967. I n f l u e n c e o f d i e t a r y supplement o f l y s i n e f e d a t two l e v e l s o f p r o t e i n on growth, f e e d e f f i c i e n c y and c a r c a s s c h a r a c t e r i s t i c s o f s w i n e . J . Anim. S c i . 26: 323. K e i t h , M.O., C h r i s t e n s e n , D.A. and Owen, B.D. 1972. D e t e r m i n a t i o n o f t h e m e t h i o n i n e r e q u i r e m e n t o f growing p i g s u s i n g serum f r e e amino acids. Can. J . Anim. S c i . 52: 163. Kohler,  G.O. and P a l t e r , R. 1967. S t u d i e s on methods f o r amino a c i d a n a l y s i s o f wheat p r o d u c t s . C e r e a l Chem. 44: 512.  K r a t z e r , F.H. 1944. Amino a c i d a b s o r p t i o n J . B i o l . Chem. 153: 237.  and u t i l i z a t i o n i n t h e c h i c k .  K r o e n i n g , G.H., Pond, W.G. and L o o s l i , J.K. 1962. M e t h i o n i n e r e q u i r e m e n t o f t h e s u c k l i n g age p i g . Summary o f R e s e a r c h Swine D i v i s i o n . Department o f A n i m a l Husbandry, C o r n e l l U n i v e r s i t y . K r o e n i n g , G.H., Pond, W.G. and L o o s l i , J.K. 1965. D i e t a r y m e t h i o n i n e c y s t i n e r e q u i r e m e n t o f t h e baby p i g as a f f e c t e d by t h r e o n i n e and p r o t e i n l e v e l s . J . Anim. S c i . 24: 519. Laxv-rence, T . L . J . 1971. H i g h - l e v e l c e r e a l d i e t s f o r t h e g r o w i n g / f i n i s h i n g p i g . V. A c o m p a r i s o n o f f i n i s h e r d i e t s c o n t a i n i n g h i g h l e v e l o f maize on b a r l e y w i t h w i d e o r narrow c a l o r i e / p r o t e i n / l y s i n e r a t i o n s when f e d t o g i v e two d i f f e r e n t c a l o r i e i n t a k e s . J . Agr. S c i . Camb. 73: 433. Lee,  C , McBee, J . L . , J r . and H o r v a t h , D.T. 1967. D i e t a r y p r o t e i n and some c a r c a s s t r a i t s . J . Anim. S c i . 26: 490.  level  - 132 -  L e r n e r , J.T. 1968, C o n t r i b u t i o n a l ' e t u d e du b e s o i n en l y s i n e , en r e l a t i o n avec l e t a u x e n e r g e t i q u e chez l e r a t e t l e p o r e . T h e s i s . Univ. P a r i s . France. Lodge, G.A., Cundy, M.E., Cooke, R. and L e w i s , D. 1972a. I n f l u e n c e o f energy and p r o t e i n c o n c e n t r a t i o n i n t h e d i e t on t h e performance o f growing p i g s . 2. D i f f e r i n g n u t r i e n t d e n s i t y a t a c o n s t a n t energy: protein ratio. Anim. P r o d . 14: 47. Lodge, G.A., Hardy, B. and L e w i s , D. 1972b. I n f l u e n c e o f energy and p r o t e i n c o n c e n t r a t i o n i n t h e d i e t on t h e performance o f growing p i g s . 4. E f f e c t s o f s e x on response t o d i e t a r y p r o t e i n l e v e l . Anim. P r o d . 14: 229. Lougnon, J . and B r e t t e , A. 1971. C o n t r i b u t i o n t o t h e e s t i m a t i o n o f t h e t h r e o n i n e r e q u i r e m e n t o f growing p i g s . Ann. Zootech. 20: 398. Manner, M.J. and McCrea, M.R. 1963. Changes i n the c h e m i c a l c o m p o s i t i o n o f sow-reared p i g l e t s d u r i n g t h e 1 s t month o f l i f e . B r i t . J . Nutr. 17: 495. Mauron, J . 1961. The concept o f amino a c i d a v a i l a b i l i t y and i t s b e a r i n g on p r o t e i n e v a l u a t i o n . I n " P r o g r e s s i n M e e t i n g P r o t e i n Needs o f I n f a n t s and P r e s c h o o l C h i l d r e n " . P r o c . Symp. 1960. ( L . V o r i s , ed.) p. 425-442. P u b i s . Natn. Res. Coun., Wash. No. 843. Mauron, J . , M o t t u , F., B u j a r d , E. and E g l i , R.H. 1955. The a v a i l a b i l i t y of l y s i n e , m e t h i o n i n e and t r y p t o p h a n i n condensed m i l k and m i l k powder. I n v i t r o , d i g e s t i o n s t u d i e s . A r c h s . Biochem. B i o p h y s . 59: 433. McWard, G.W., B e c k e r , D.E., N o r t o n , H.W., T e r r i l l , S.W. and J e n s e n , A.H. 1959. The l y s i n e r e q u i r e m e n t o f w e a n l i n g swine a t two l e v e l s o f d i e t a r y p r o t e i n . J . Anim. S c i . 18: 1059. Meade, R . J . 1956a. The i n f l u e n c e o f m e t h i o n i n e s u p p l e m e n t a t i o n o f 12, 14 and 16 p e r c e n t p r o t e i n corn-soybean o i l meal d i e t s upon n i t r o g e n b a l a n c e o f growing s w i n e . J . N u t r . 60: 5 9 9 . . . Meade, R . J . 1956b. The i n f l u e n c e o f t r y p t o p h a n , m e t h i o n i n e and l y s i n e s u p p l e m e n t a t i o n of. a corn-soybean o i l meal d i e t on n i t r o g e n b a l a n c e o f growing swine. J . Anim. S c i . 15: 288. Meade, R . J . , Dukelow, W.R. and G r a n t , R.S. 1966a. I n f l u e n c e o f p e r c e n t o a t s i n the d i e t , l y s i n e and m e t h i o n i n e s u p p l e m e n t a t i o n , and of p e l l e t i n g on r a t e and e f f i c i e n c y o f g a i n o f growing p i g s and on carcass c h a r a c t e r i s t i c s . J . Anim. S c i . 25: 58.  - 133 -  Meade, R . J . , Dukelow, W.R. and Grand, R.S. 1966b. L y s i n e and m e t h i o n i n e a d d i t i o n t o c o r n - s o y b e a n meal d i e t s f o r growing s w i n e : E f f e c t s on r a t e and e f f i c i e n c y o f g a i n and c a r c a s s c h a r a c t e r i s t i c s . J . Anim. Soc. 25: 78. Meade, R . J . , Vermedahl, L.D., Rusk, J.W. a n d W a s s , D.F. 1969. E f f e c t s o f p r o t e i n c o n t e n t o f the d i e t o f the young p i g on r a t e and e f f i c i e n c y o f g a i n d u r i n g e a r l y development and subsequent t o 23.5 k g and c a r c a s s c o m p o s i t i o n o f l e a n t i s s u e . J . Anim. S c i . 28: 473. M e r t z , E.T., Beeson, W.M. and J a c k s o n , II.D. 1952. C l a s s i f i c a t i o n o f e s s e n t i a l amino a c i d s f o r the w e a n l i n g p i g . A r c h . Biochem. 38: 121. Mertz, E.T., Delong, D.C. and Beeson, W.M. 1955. H i s t i d i n e and leucine reauirements of the weanling p i g . J . Anim. S c i . 14: 1217. Mertz, E.T., Shelton, D.C. and Beeson, W.M. 1949. The amino acid requirement of swine : l y s i n e . J . Anim. S c i . 8: 524. Metta, V.C. and M i t c h e l l , H.H. 1956. A comparison of the b i o l o g i c a l values of dietary p r o t e i n incorporated i n high-fat and low-fat d i e t s . J . Nutr. 59: 501. M i n e r , J . J . , Clower, W.B. and N o l a n d , P.R. 1955. Amino a c i d s u p p l e m e n t a t i o n o f a c o r n - c o t t o n s e e d meal d i e t f o r g r o w i n g - f a t t e n i n g s w i n e . J . Anim. S c i . 14: 24. M i t c h e l l , J.R., J r . , Becker,. D.E., J e n s e n , A.H., N o r t o n , H.W. and Harmon, B.G. 1965a. L y s i n e need o f s w i n e a t two s t a g e s o f development. J . Anim. S c i . 24: 409. M i t c h e l l , J.R., J r . , B e c k e r , D.E., J e n s e n , A.H., N o r t o n , H.W. and Harmon, B.G. 1965b. C a l o r i c d e n s i t y o f the d i e t and the l y s i n e need o f growing s w i n e . J . Anim. S c i . 24: 977. M i t c h e l l , J.R., J r . , B e c k e r , D.E., N o r t o n , H.W., Harmon, B.G. and J e n s e n , A.H. 1968b. D e t e r m i n a t i o n o f amino a c i d needs o f t h e young p i g by n i t r o g e n b a l a n c e and plasma f r e e amino a c i d s . J . Anim. S c i . 27: 1327. M i t c h e l l , J.R., J r . , B e c k e r , D.E., Harmon, B.G., N o r t o n , H.W. and J e n s e n , A.H. 1968a. Some amino a c i d needs o f t h e young p i g f e d a s e m i s y n t h e t i c diet. J . Anim. S c i . 27: 1322. Moore, S.  1963. On the d e t e r m i n a t i o n o f c y s t i n e as c y s t e i c a c i d . Chem. 238: 235.  J. Biol.  - 134 -  M o r r i s o n , A.E., M i d d l e t o n , E . J . and McLaughlan, J.M. 1961. B l o o d amino a c i d s t u d i e s . I I . E f f e c t s of d i e t a r y l y s i n e concentration, sex and growth r a t e on plasma f r e e l y s i n e and t h r e o n i n e l e v e l s i n the r a t . Can. J . Biochem. P h y s i o l . 39: 1675. M o r r i s o n , M.A. and H a r p e r , A.E. 1960. Amino a c i d b a l a n c e and i m b a l a n c e . IV. S p e c i f i t y o f t h r e o n i n e i n p r o d u c i n g an i m b a l a n c e i n d i e t s d e f i c i e n t i n n i a c i n and t r y p t o p h a n . J . N u t r . 71: 296. M i i l l e r , Z., K o z e l , V., B a u e r , B., S t r u n c , M. and Moravec, J . 1967c. E n r i c h m e n t o f c e r e a l d i e t s f o r f a t t e n i n g p i g s from 35 Kg l i v e w e i g h t w i t h l y s i n e , t h r e o n i n e , t r y p t o p h a n and m e t h i o n i n e . B i o l . Chem. V y z i v y Z v i r a t . 3: 399. M i i l l e r , Z., K o z e l , V., H e j z l a r , Z., B a v e r , B. and Moravec, J . 1967a. L y s i n e i n c o m b i n a t i o n w i t h a n o t h e r l i m i t i n g amino a c i d i n t h e n u t r i t i o n o f weaned p i g l e t s . B i o l . Chem. V y z i v y Z v i r a t 3: 411. M i i l l e r , Z.and M a l e k , I . 1967a. Monodiet based on wheat f o r weaned p i g l e t s . B i o l . Chem. V y z i v y Z v i r a t 3: 535. M i i l l e r , Z. and M a l e k , I . 1967b. Monodiet based on b a r l e y f o r weaned piglets. B i o l . Chem. V y z i v y Z v i r a t 3: 543. M i i l l e r , Z. and M a l e k , I . 1967c. Monodiet b a s e d on maize f o r weaned p i g l e t s . B i o l . Chem. V y z i v y Z v i r a t 3: 551. M i i l l e r , Z., P a l k o s k a , J . , D r e v j a n y , L. and Moravec, J . 1967b. Cereal diets e n r i c h e d w i t h l y s i n e , t h r e o n i n e , t r y p t o p h a n and m e t h i o n i n e i n t h e n u t r i t i o n o f weaned p i g l e t s . B i o l . Chem. V y z i v y Z v i r a t 3: 423. M i i l l e r , Z. and Rozman, J . 1968. M o n o c e r e a l d i e t s f o r t i f i e d w i t h l y s i n e , t h r e o n i n e , t r y p t o p h a n and m e t h i o n i n e i n p i g f a t t e n i n g . Chem. V y z i v y Z v i r a t 4: 433.  Biol.  N.A.S.-N.R.C. 1968. N u t r i e n t Requirement o f Domestic A n i m a l s . 2. N u t r i e n t Requirement o f Swine. 6 t h e d . P u b l . 1599, Washington,.D.C. N.A.S.-N.R.C. 1972. N u t r i e n t Requirements o f Domestic A n i m a l s . 10. N u t r i e n t Requirements o f L a b o r a t o r y A n i m a l s . 2nd E d i t i o n . N a t i o n a l Academy o f S c i e n c e s , Washington, D.C. N e w e l l , J.A. and Bowland, J . P . 1972. P e r f o r m a n c e , c a r c a s s c o m p o s i t i o n , and f a t c o m p o s i t i o n o f b o a r s , g i l t s and barrows f e d two l e v e l s o f protein. Can. J . Anim. S c i . 52: 543. N i e l s e n , A . J . 1971. The d i g e s t i b i l i t y o f amino a c i d d i f f e r e n t b a l a n c e d feed r a t i o n s as r e l a t e d t o d i g e s t i b i l i t y o f n i t r o g e n i n growing pigs. A c t a . A g r . Scand. 21: 189.  - 135 -  N i e l s e n , H.E., Hays, V.W., Speer, V.C. and C a t r o n , D.V. 1963. L y s i n e s u p p l e m e n t a t i o n o f c o r n - and b a r l e y - b a s e d i e t s f o r growingf i n i s h i n g swine. J . Anim. S c i . 22: 454. N i x o n , S.E. and Mawer, G.E. 1970a. The d i g e s t i o n and a b s o r p t i o n o f p r o t e i n i n man. 1. The s i t e of a b s o r p t i o n . B r i t . J . N u t r . 24: 227. N i x o n , S.E. and Mawer, G.E. 1970b. The d i g e s t i o n and a b s o r p t i o n o f p r o t e i n i n man. 2. The form i n w h i c h d i g e s t e d p r o t e i n i s absorbed. B r i t . J . N u t r . 24: 241. O ' D e l l , B.L., L a e r d a l , O.A., J e f f a y , A.M. and Savage, J.E. 1958. A r g i n i n e m e t a b o l i s m i n t h e growing c h i c k . P o u l t r y S c i . 37: 817. Oestemer, G.A., Hanson, L.E. and Meade, R . J . 1973. L e u c i n e - i s o l e u c i n e i n t e r r e l a t i o n s h i p i n the young p i g . J . Anim. S c i . 36: 674. Oestemer, G.A., Meade, R . J . , S t o c k l a n d , W.L. and Hanson, L.E. 1970. M e t h i o n i n e s u p p l e m e n t a t i o n o f opaque-2 c o r n f o r growing s w i n e . J . Anim. S c i . 31: 1133. Oh, S., Summers, J.D. and Wood, A.S. 1972. A v a i l a b i l i t y o f m e t h i o n i n e i n v a r i o u s p r o t e i n supplements as d e t e r m i n e d b y c h i c k b i o a s s a y . Can. J . Anim. S c i . 52: 171. O l s e n , E.M., Summers, J.D. and S l i n g e r , S . J . 1968. B i o l o g i c a l a v a i l a b i l i t y o f amino a c i d s i n wheat b y - p r o d u c t s . Can. J . Anim. S c i . 48: 221. O r t e n , A.V. 1963. R e s e a r c h approaches to amino a c i d n u t r i t i o n . phase o f amino a c i d n u t r i t i o n . F e d . P r o c . 22: 1103.  Intestinal  O s t r o w s k i , H. 1969. The e f f e c t s o f d i e t a r y s u p p l e m e n t a t i o n w i t h l y s i n e and m e t h i o n i n e on body and t i s s u e c o m p o s i t i o n i n p i g . Anim. P r o d . 11: 521. O s l a g e , H.J. 1962. Body c o m p o s i t i o n and a c c r e t i o n o f m a t t e r b y growing f a t t e n i n g p i g s and the i n f l u e n c e o f n u t r i t i o n . 1. Statement o f the problem and methods o f s t u d y . Z e i t s c h r i f t f u r T i e r p h y s i o l o g i e , T i e r e r n a h r u n g und F u t t e r m i t t e l k u n d e 17: 350. O s l a g e , H.J., F l i e g e l , H., F a r r i e s , F.E. and R i c h t e r , K. 1966. A c c r e t i o n o f N, f a t and energy by growing f a t t e n i n g p i g s . Z e i t h s c h r i f t f u r T i e r p h y s i o l o g i e , T i e r e r n a h r u n g und F u t t e r m i t t e l k u n d e 21: 50. P e l l e t t , P.L. (Ed.) 1963. E v a l u a t i o n o f P r o t e i n Q u a l i t y . Res. Coun., Wash. No. 1100. .  P u b i s . Natn.  P i c k , R.T. and Meade, R . J . 1971. Amino a c i d s u p p l e m e n t a t i o n o f opaque-2 c o r n d i e t s f o r growing r a t s . J . N u t r . 101: 1241.  - 136 -  P i e r c e , A.B. and Bowland, J.P. 1972. P r o t e i n amino a c i d l e v e l s and sequence i n swine d i e t s : E f f e c t s on g a i n f e e d c o n v e r s i o n and c a r c a s s c h a r a c t e r i s t i c s . Can. J . Anim. S c i . 52: 531. Pond, W.G., H i l l i e r , J.C. and B e n t o n , D.A. 1958. The amino a c i d adequacy o f m i l o f o r t h e growth o f r a t s . J . N u t r . 65: 493. Pond, W.G.  and J o n e s , J.R. 1964. Amino a c i d s u p p l e m e n t a t i o n t o c o r n d i e t s f o r f i n i s h i n g p i g s . C o r n e l l Swine Mimeo. 64-1.  Rama Rao, P.B., M e t t a , V.C. and Johnson, B.C. 1959. The amino a c i d compos i t i o n and n u t r i t i v e v a l u e o f p r o t e i n s . I . E s s e n t i a l amino a c i d r e q u i r e m e n t s o f t h e growing r a t . J . N u t r . 69: 387. Rama Rao, P.B., M e t t a , V . C , N o r t o n , H.W. and Johnson, B.C. 1960. The amino a c i d c o m p o s i t i o n and n u t r i t i v e v a l u e o f p r o t e i n s . I I I . The t o t a l p r o t e i n and t h e n o n e s s e n t i a l amino a c i d r e q u i r e m e n t . J . N u t r . 71: 361. R 6 r a t , A.  1961. A l i m e n t a t i o n a z o t e e des animaux domestiques. Colloque S c i e n t i f i q u e , P a r i s , F r a n c e . A s s o c i a t i o n F r a n c a i s e de Z o o t e c h n i e .  R e r a t , A.  1972. P r o t e i n n u t r i t i o n and m e t a b o l i s m i n t h e growing p i g . N u t r . A b s t r . and Rev. 42: 13.  R£rat, A. and Henry, Y. 1963. B e s o i n en l y s i n e du r a t en c r q i s s a n c e : p r i n c i p e d'une m e t h o d o l o g i e e t r e s u l t a t s e x p e r i m e n t a u x . C.R.. Acad. S c i . , P a r i s . 257: 3045. R e r a t , A. and Henry, Y. 1964. The p r o t e i n r e q u i r e m e n t s o f t h e growing pig 1. The u t i l i z a t i o n o f t h e f i s h meal a t t h r e e d i f f e r e n t l e v e l s . Ann. Zootech. 13: 5. R£rat, A. and Henry, Y. 1969. S u p p l e m e n t a t i o n des c£r£ales p a r l e s a c i d e s amines chez l e p o r e pendant l a p e r i o d e de d e f i n i t i o n . J o u r n e e s de l a Recherche P o r c i n e en France. I.N.R.A., P a r i s , 143. R e r a t , A. and H e n r y , Y. 1970. S u l f u r - a m i n o a c i d s need o f t h e growing p i g . Annales Zootech. 19: 486. R£rat, A., H e n r y , Y. and Desmoulin, B. 1971 The i n f l u e n c e o f energy r e s t r i c t i o n on t h e p r o t e i n need o f t h e female growing p i g . Journees de Recherche P o r c i n e en F r a n c e , P a r i s . I.N.R.A. p. 65. R£rat, A. and Lougnon, J . 1968. Amino a c i d r e q u i r e m e n t s o f growing p i g s . W o r l d Review o f A n i m a l P r o d u c t i o n . . 4: 84. R£rat, A. and Lougnon, J . 1965. S u p p l e m e n t a t i o n p u r l a L - l y s i n e d'un regime v e g e t a l s i m p l i f i e chez l e p o r e en c r o i s s a n c e . Ann. Z o o t e c h . 14: 247.  - 137 -  R e r a t , A., Lougnon, J . and P i o n , R. 1962. S u p p l e m e n t a t i o n by DL-methionine o f a complex d i e t f o r growing f i n i s h i n g p i g . Ann. Z o o t e c h . 11: 159. R d r a t , A., L e r n e r , J . , Henry, Y. and Bourdon, D. 1970. Etude du b e s o i n de l y s i n e du pore en c r o i s s a n c e en r e l a t i o n avec l e t a u x e n e r g e t i q u e du regime. J o u r e e s de l a Recherche P o r c i n e en F r a n c e . P a r i s . I.N.R.A. p. 79. R i p p o n , W.P. 1959. Some e r r o r s i n t h e d e t e r m i n a t i o n o f n i t r o g e n r e t e n t i o n of sheep by n i t r o g e n b a l a n c e s t u d i e s . B r i t . J . N u t r . 13: 243. R o b i n s o n , D.W. 1964. The p l a n e o f n u t r i t i o n and compensatory p i g s . Anim. P r o d . 6: 229.  growth i n  R o b i n s o n , D.W. 1965 . The p r o t e i n and energy n u t r i t i o n o f t h e p i g . 1. The e f f e c t o f v a r y i n g t h e p r o t e i n and energy l e v e l s i n t h e ' f i n i s h i n g d i e t ' o f heavy p i g s . J . A g r i c . S c i . 6 5 : 405. R o b i n s o n , D.W. and L e w i s , D. 1963. Amino a c i d s u p p l e m e n t a t i o n o f a b a r l e y r a t i o n f o r t h e p i g . J . S c i . F d . A g r . 14: 806. R o b i n s o n , D.W. and L e w i s , D. 1964. P r o t e i n and energy n u t r i t i o n o f t h e b a c o n p i g . I I . The e f f e c t o f v a r y i n g t h e p r o t e i n and energy l e v e l s i n d i e t s o f ' f i n i s h i n g ' p i g s . J . A g r i c . S c i . 63: 185. R o b i n s o n , D.W., Morgan, J.T. and L e w i s , D. 1964. P r o t e i n and energy n u t r i t i o n o f t h e bacon p i g . 1. The e f f e c t o f v a r y i n g p r o t e i n and energy l e v e l s i n t h e d i e t s o f 'growing' p i g s . J . A g r i c . S c i . 62: 369. R o g e r s , Q.R., Tannous, R.T. and H a r p e r , A.E. 1967. E f f e c t s o f e x c e s s l e u c i n e on growth and f o o d s e l e c t i o n . J . N u t r . 91: 561. Rose, W.C.  1938. The n u t r i t i v e s i g n i f i c a n c e o f t h e amino a c i d s . Review. 18: 109.  Physiol.  Rose, W.C, S m i t h , L . C , Womack, M. and Shane, M. 1949. The u t i l i z a t i o n of t h e n i t r o g e n o f ammonium s a l t s , u r e a , and c e r t a i n o t h e r compounds i n t h e s y n t h e s i s o f n o n e s s e n t i a l amino a c i d s i n v i v o . J . B i o l . Chem. 181: 307. Rosenberg, H.R. 1959. Amino a c i d s u p p l e m e n t a t i o n o f foods and f e e d s . I n P r o t e i n and Amino A c i d N u t r i t i o n . E d i t . A.A. A l b a n e s e , Academic P r e s s , New Y o r k . p. 381. Rosenberg, H.R., B a l d i n i , J.T., Sunde, M.L., B i r d , H.R. and R u n n e l s , T.D. 1955. The c o n c o m i t a n t o f f a t and m e t h i o n i n e i n b r o i l e r d i e t s . P o u l t r y S c i . 34: 1308.  - 138 -  Rosenberg, H.R. and C u l i k , R. 1955. L y s i n e r e q u i r e m e n t o f t h e growing r a t as a f u n c t i o n o f the p r o d u c t i v e energy l e v e l o f t h e d i e t . J . Anim. S c i . 14: 1221. Rosenberg, H.R., C u l i k , R. and E c k e r t , R.E. 1959. L y s i n e and t h r e o n i n e supplementation of r i c e . J . N u t r . 69: 217. Rozman, I . , M u l l e r , Z., P l o c e k , F. and S i l e r , R. 1968. The i n f l u e n c e o f l y s i n e , t h r e o n i n e , t r y p t o p h a n and m e t h i o n i n e supplemented t o p i g s f e d c e r e a l d i e t w i t h o u t p r o t e i n f e e d s . B i o l . Chem. V y z i v y Z v i r a t . 4: 441. Saben, H.S. and Bowland, J.P. 1971. Comparative e v a l u a t i o n o f some t e c h n i q u e s used i n d e t e r m i n a t i o n o f n i t r o g e n and energy c o n t e n t o f f e c e s from p i g s . Can. J . Anim. S c i . 51: 793. Salmon, W.D. 1954. The t r y p t o p h a n r e q u i r e m e n t o f t h e r a t as a f f e c t e d by n i a c i n and l e v e l o f d i e t a r y n i t r o g e n . A r c h . Biochem. B i o p h y s . 51: 30. Sauer, W.C. 1972. A v a i l a b i l i t y o f amino a c i d s from b a r l e y , wheat, t r i t i c a l e and soybean meal f o r growing p i g s . M.Sc. T h e s i s , U n i v e r s i t y of Manitoba, Winnipeg, Manitoba. Scrimshaw, N.S. and A l t s c h u l , A.M. 1971. Amino A c i d F o r t i f i c a t i o n o f P r o t e i n Foods. Ed. by Scrimshaw and A l t s c h u l , MIT P r e s s . S e w e l l , R.F., A b e r n a t h y , R.P. and T a r p l e y , R.L. 1956. I n t e r r e l a t i o n s h i p o f p r o t e i n , l y s i n e and energy i n d i e t s f o r growing s w i n e . J . Anim. S c i . 15: 1233. S e w e l l , R.F., L o o s l i , J.K., Maynard, L.A., W i l l i a m s , H.H. and S h e f f y , B.E. 1952. The q u a n t i t a t i v e t h r e o n i n e r e q u i r e m e n t o f s u c k l i n g p i g . J . N u t r . 49: 435. S h e l t o n , D.C, Beeson, W.M. and M e r t z , E.T. 1950. Growth o f w e a n l i n g p i g s on a d i e t c o n t a i n i n g t e n p u r i f i e d amino a c i d s . A r c h . Biochem. Biophys. 29: 446. S h e l t o n , D.C, Beeson, W.M. and M e r t z , E.T. 1951a. The e f f e c t o f m e t h i o n i n e and c y s t i n e on the growth o f w e a n l i n g p i g s . J . Anim. S c i . 10: 57. S h e l t o n , D.C, Beeson, W.M. and M e r t z , E.T. 1951b. Q u a n t i t a t i v e D L - t r y p t o phan r e q u i r e m e n t o f t h e w e a n l i n g p i g . J . Anim. S c i . 10: 73. Shimada, A. and C l i n e , T.R. 1974. L i m i t i n g , a m i n o a c i d s o f t r i t i c a l e f o r t h e growing r a t and p i g . J . Anim. S c i . 38: 9 4 1 .  - 139 -  S m i t h , R.C. 1972. A c e t y l a t i o n o f m e t h i o n i n e s u l f o x i d e and m e t h i o n i n e s u l f o n e by t h e r a t . B i o c h i m . B i o p h y s . A c t a . 261: 304. S m i t h , J . , J r . , Clawson, A . J . and B a r r i c k , E.R. 1967. E f f e c t o f r a t i o o f p r o t e i n from c o r n and soybean meal i n d i e t s o f v a r y i n g t o t a l p r o t e i n on performance, c a r c a s s d e s i r a b i l i t y and d i e t d i g e s t i b i l i t y i n s w i n e . J . Anim. S c i . 26: 752. S m i t h , G.H. and L e w i s , D. 1966. A r g i n i n e i n p o u l t r y n u t r i t i o n . 3. Agent and t a r g e t i n amino a c i d i n t e r a c t i o n . B r i t . J . N u t r . 20: 621. Snedecor, G.W. and Cochran, W.G. 1967. S t a t i s t i c a l Methods. The Iowa S t a t e U n i v e r s i t y P r e s s , Ames Iowa, U.S.A.  6th Edition.  S o l d e v i l a , M. and Meade, R . J . 1964. B a r l e y r a t i o n s f o r s w i n e . I I . The i n f l u e n c e o f L - l y s i n e and DL-methionine s u p p l e m e n t a t i o n o f b a r l e y soybean meal d i e t s upon r a t e and e f f i c i e n c y o f g a i n and upon n i t r o g e n r e t e n t i o n o f growing s w i n e . J . Anim. S c i . 23: 394. Sowers, J.E. and Meade, R.J. 1972a. T h r e o n i n e r e q u i r e m e n t o f t h e growing p i g . J . Anim. S c i . 35: 224 ( A b s t r . ) . Sowers, J.E. and Meade, R . J . 1972b. E f f e c t o f p r o t e i n l e v e l on t h e t h r e o n i n e r e q u i r e m e n t o f t h e p i g . J . Anim. S c i . 35: 224 ( A b s t r . ) . S t a n d i s h , J . F . and Bowland, J.P. 1967. E f f e c t s o f v a r y i n g d i e t a r y energy, p r o t e i n and amino a c i d l e v e l s on growth, n u t r i e n t d i g e s t i b i l i t y , and serum p r o t e i n l e v e l s o f e a r l y weaned p i g s . Can. J . Anim. S c i . 47: 77. S t o c k l a n d , W.L., L a i , Y.F., Meade, R.J., Sowers, J . E . and Oestemer, G.A. 1971. L - p h e n y l a l a n i n e and L - t y r o s i n e r e q u i r e m e n t s o f t h e growing r a t . J . N u t r . 101: 177. S t o c k l a n d , W.L., Meade, R . J . and M e l l i e r e , A.L. 1970. L y s i n e r e q u i r e m e n t o f t h e growing r a t : plasma f r e e l y s i n e as a response c r i t e r i o n . J . N u t r . 100: 925. S t u c k i , W.P. and H a r p e r , A.E. 1962. E f f e c t s o f a l t e r i n g t h e r a t i o o f i n d i s p e n s a b l e t o d i s p e n s a b l e amino a c i d s i n d i e t s f o r r a t s . J . N u t r . 78: 278. Sure, B.  1954. P r o t e i n s u p p l e m e n t a t i o n r e l a t i v e n u t r i t i v e v a l u e s o f p r o t e i n i n whole wheat and whole r y e and e f f e c t o f amino a c i d supplements. J . A g r . Food Chem. 2: 1008.  Sure, B.  1955. R e l a t i v e n u t r i t i v e v a l u e o f p r o t e i n i n food and supplement a r y v a l u e o f amino a c i d s i n p e a r l e d b a r l e y and peanut f l o u r . J . A g r . Food. Chem. 3: 789.  - 140 -  Thorbek, G. 1969. N i t r o g e n m e t a b o l i s m i n g r o w i n g p i g s . Commission d'Etude de l a F e d e r a t i o n Europ£ene de Z o o t e c h n i e , H e l s i n k i , Finland. Tjong-A-Hung, Hans on, L.E., R u s t , J.W. and Meade, R.J. 1972. E f f e c t s o f p r o t e i n l e v e l sequence and sex on r a t e and e f f i c i e n c y o f g a i n o f growing s w i n e , and on c a r c a s s c h a r a c t e r i s t i c s , i n c l u d i n g c o m p o s i t i o n o f l e a n t i s s u e . J . Anim. S c i . 35: 760. Tukey, J.W. 1953. The P r o b l e m o f M u l t i p l e Comparisons. U n i v e r s i t y , P r i n c e t o n , N.J.  Ditto Princeton  Welch, J . , C o r d t s , R.H. and Vander Noot, G.W. 1966. E f f e c t o f l y s i n e , m e t h i o n i n e and t r y p t o p h a n s u p p l e m e n t a t i o n upon n i t r o g e n r e t e n t i o n o f b a r r o w s . J . Anim. S c i . 25: 806. W i l l i a m s , H.H., C u r t i n , L.V., Abraham, J . , L o o s l i , J.K. and Maynard, L.A. 1954. E s t i m a t i o n of growth r e q u i r e m e n t s f o r amino a c i d s by a s s a y o f the c a r c a s s . J . B i o l . Chem. 141: 375. W i l l i a m s , M.A. and Grau, C.R. 1956. Food i n t a k e and u t i l i z a t i o n of l y s i n e d e f i c i e n t p r o t e i n by c h i c k i n r e l a t i o n t o t h e d i g e s t i b l e energy c o n c e n t r a t i o n o f the d i e t . J . N u t r . 59: 243. Wong, W.C.,  B o y l a n , W.J. and S t o t h e r s , S.C. 1968. E f f e c t s o f d i e t a r y p r o t e i n l e v e l and s e x on swine performance and c a r c a s s t r a i t s . Can. J . Anim. S c i . 48: 383.  Wood, A . J . and G r o v e s , T.D.D. 1965. Body c o m p o s i t i o n s t u d i e s on t h e s u c k l i n g p i g . 1. M o i s t u r e , c h e m i c a l f a t , t o t a l p r o t e i n , and t o t a l ash i n r e l a t i o n t o age and body w e i g h t . Can. J . Anim. S c i . 45: 8. W r e t l i n d , K.A.J. 1949. The e f f e c t o f s y n t h e t i c amino a c i d s e s s e n t i a l f o r growth on t h e body w e i g h t o f growing r a t s , and the s y n t h e s i s o f the amino a c i d s used. A c t a p h y s i o l . Scand. m. S u p p l . 59. Young, L.G., Ashton,.G.C., Forshaw, R.P. and Ingram, R.H. 1968. Relations h i p o f d i e t a r y p r o t e i n l e v e l s t o performance and c a r c a s s m e r i t o f market s w i n e . Can. J . Anim. S c i . 48: 71. Van Soest,P.J.1963.Use o f d e t e r g e n t s i n the a n a l y s i s o f f i b r o u s f e e d . I I . A r a p i d method f o r the d e t e r m i n a t i o n o f f i b r e and l i g n i n . J.A.O.A.C. 46: 829. Veum, W.H.,  P f a n d e r , W.H. and B e l l a m y , C.G. 1973. Opaque-2 and n o r m a l c o r n supplemented w i t h soybean-meal and/or amino a c i d f o r g r o w i n g r a t s . J . Anim. S c i . 37: 63.  - 141 -  Zimmerman, R.A. and S c o t t , H.M. 1965. I n t e r r e l a t i o n s h i p s o f plasma amino a c i d l e v e l s and w e i g h t g a i n i n t h e c h i c k as i n f l u e n c e d by s u b o p t i m a l and s u p e r o p t i m a l d i e t a r y c o n c e n t r a t i o n s o f s i n g l e amino a c i d s . J . N u t r . 87: 13.  - 142 -  X.  APPENDIX  Table 1A IB  2A 2B  3A 3B  4A 4B  5A  5B 6A  6B  Page Average feed intake (Kg) per p i g per day f o r each diet on dry matter basi§ i n P i g Experiment I  145  Analysis of variance of average d a i l y feed intake i n Pig Experiment I  145  Mean daily gain (Kg) from s t a r t to 45 Kg body weight of 108 pigs i n Pig Experiment I  146  Analysis of variance of main daily gain from s t a r t to 45 Kg body weight of 108 pigs with s t a r t i n g weight as covariable i n P i g Experiment I  147  Mean daily gain (Kg) from 45 Kg body weight to f i n i s h of 108 pigs i n P i g Experiment I  148  Analysis of variance of main daily gain from 45 Kg body weight to f i n i s h of 108 pigs with no covariable i n P i g Experiment I  149  Mean daily gain (Kg) from s t a r t to f i n i s h of 108 pigs i n Pig Experiment I  150  Analysis of varaince of mean daily gain from s t a r t to f i n i s h of 108 pigs with starting weight as covariable i n P i g Experiment I  151  Average feed conversion e f f i c i e n c y r a t i o per p i g (D.M. feed intake (Kg)/weight gain (Kg)) i n Pig Experiment I  152  Analysis of variance of feed conversion e f f i c i e n c y r a t i o i n P i g Experiment I  152  Total back fat (mm) of 107 pigs i n Pig Experiment I  153  Analysis of variance of t o t a l back f a t thickness with f i n a l body weight, average body weight gain and body length as covariables i n Pig Experiment I  154  - 143 -  Table  7A 7B  Page  Back f a t 40 mm from m i d - l i n e (mm) i n P i g Experiment I  o f 107  pigs 155  A n a l y s i s o f v a r i a n c e o f b a c k f a t 40 mm from mid l i n e w i t h f i n a l body w e i g h t , average d a i l y g a i n and body l e n g t h as c o v a r i a b l e s i n P i g Experiment I  156  2 8A 8B  Eye muscle a r e a (mm Experiment I  ) o f 107 p i g s i n P i g 157  A n a l y s i s o f v a r i a n c e o f eye muscle a r e a w i t h f i n a l body w e i g h t , average d a i l y g a i n and body l e n g t h as c o v a r i a b l e s i n P i g E x p e r i m e n t I  158  2 9A 9B  Eye muscle i n d e x ( l e n g t h 'A' x w i d t h o f the 107 p i g s i n P i g E x p e r i m e n t I  'B')  (mm  ) 159  A n a l y s i s o f v a r i a n c e of eye muscle i n d e x ( l e n g t h x w i d t h ) w i t h f i n a l body w e i g h t , average d a i l y g a i n and body l e n g t h as c o v a r i a b l e s i n P i g Experiment I  160  10A  Days on t r i a l s o f 108 p i g s i n P i g E x p e r i m e n t I  161  10B  A n a l y s i s o f v a r i a n c e of days on t r i a l s w i t h  initial  body w e i g h t as c o v a r i a b l e i n P i g E x p e r i m e n t I  162  11A  D.M.  163  11B  A n a l y s i s of v a r i a n c e of D.M. feed i n t a k e (g)/wk. i n P i g Experiment I I A n a l y s i s o f v a r i a n c e o f N i n t a k e (g)/wk. i n  163  Pig  164  12  f e e d i n t a k e (g)/wk. i n P i g E x p e r i m e n t I I  Experiment I I  13A  P e r c e n t a g e D.M.  13B  A n a l y s i s o f v a r i a n c e of d r y m a t t e r d i g e s t i b i l i t y i n percent i n P i g Experiment I I N i t r o g e n r e t e n t i o n (g)/wk. i n P i g E x p e r i m e n t I I  165 166  A n a l y s i s of variance f o r n i t r o g e n r e t e n t i o n i n P i g Experiment I I  166  14A 14B  digestibility  i n P i g Experiment I I  165  - 144 -  Table  14C 14D  15A  15B 16A 16B  17A  17B  18  19  20  Page  A n a l y s i s of c o - v a r i a n c e o f n i t r o g e n r e t e n t i o n w i t h f e e d i n t a k e as c o v a r i a b l e i n P i g E x p e r i m e n t I I  167  A n a l y s i s of co-variance f o r n i t r o g e n r e t e n t i o n w i t h n i t r o g e n i n t a k e as c o v a r i a b l e i n P i g E x p e r i m e n t I I  167  N i t r o g e n absorbed as a p e r c e n t a g e of n i t r o g e n i n t a k e i n P i g Experiment I I  168  A n a l y s i s o f v a r i a n c e f o r n i t r o g e n absorbed as a p e r c e n t a g e of n i t r o g e n i n t a k e i n P i g E x p e r i m e n t I I  168  N i t r o g e n r e t a i n e d as a p e r c e n t a g e o f n i t r o g e n i n t a k e i n P i g Experiment I I  169  A n a l y s i s of v a r i a n c e f o r n i t r o g e n r e t a i n e d as a p e r c e n t a g e of n i t r o g e n i n t a k e i n P i g E x p e r i m e n t I I  169  N i t r o g e n r e t a i n e d as a p e r c e n t a g e o f n i t r o g e n absorbed i n P i g E x p e r i m e n t I I  170  A n a l y s i s o f v a r i a n c e o f n i t r o g e n r e t a i n e d as a p e r c e n t a g e of n i t r o g e n absorbed i n P i g E x p e r i m e n t I I  170  A n a l y s i s o f c o - v a r i a n c e f o r average d a i l y g a i n and f e e d c o n v e r s i o n e f f i c i e n c y w i t h i n i t i a l w e i g h t and d a i l y feed i n t a k e as c o v a r i a b l e s i n Rat E x p e r i m e n t s I , I I and I I I  171  A n a l y s i s o f c o - v a r i a n c e f o r PER w i t h i n i t i a l w e i g h t as a c o v a r i a b l e i n Rat E x p e r i m e n t s I , I I and I I I  172  A n a l y s i s of co-variance f o r carcass c h a r a c t e r i s t i c s of r a t s i n Rat E x p e r i m e n t s I , I I and I I I  173  -145  T a b l e 1A.  -  Average f e e d i n t a k e (kg) p e r p i g p e r day f o r each diet  on  d r y m a t t e r b a s i s i n P i g Experiment I .  Treatment  Rep 1  Rep 2  Rep 3  1  1.986  1.854  1.988  2  1.815  1.768  1.880  3  1.863  1.754  1.899  4  1.886  1.822  2.024  5  1.824  1.755  1.889  6  1.765  1.910  1.894  T a b l e I B . A n a l y s i s o f v a r i a n c e o f average d a i l y f e e d i n t a k e i n P i g Experiment I .  Source  Total  D.F.  S.S.  M.S.  F-value  Variance r a t i o F(nec.) P=0.05  P=0.01  17  0.1103  Treatment  5  0.0389  0.0078  1.8616  3.20  5.32  Covariable starting weight  1  0.0264  0.0264  6.3247*  4.82  9.65  11  0.0460  0.0042  Residual  *P < 0.05  - 146 -  T a b l e 2A.  Mean d a i l y g a i n (Kg) from s t a r t t o  45 Kg body  w e i g h t o f 108 p i g s i n P i g E x p e r i m e n t I .  Rep 1  Treatment  Rep 2  Rep 3  Male  Female  Male  Female  Male  Female  0.7500  0.6071  0.7194  0.7898  0.7143  0.6684  0.6760  0.6653  0.5833  0.6735  0.6449  0.5748  0.5561  0.6403  0.5893  0.6505  0.5310  0.6378  0.6122  0.4949  0.4216  0.4595  0.4738  0.4274  0.3036  0.4821  0.3857  0.4216  0.5281  0.4770  0.4658  0.4506  0.5867  0.5214  0.4390  0.4512  0.6714  0.4949  0.6551  0.5632  0.5714  0.4645  0.5136  0.4609  0.5274  0.5500  0.5485  0.5561  0.4680  0.4797  0.4913  0.3866  0.5095  0.5918  0.6755  0.5383  0.4879  0.5434  0.6148  0.5289  0.5561  0.5357  0.5643  0.5286  0.6490  0.5578  0.6071  0.5012  0.7296  0.5459  0.5655  0.5714  0.5060  0.5893  0.5833  0.5262  0.5017  0.5689  0.5536  0.5765  0.4727  0.5405  0.5689  0.4869  0.5442  0.5578  0.6276  0.3583  0.4524  0.5408  0.5782  0.5013  0.5867  0.5052  0.6857  0.5740  0.5405  0.5000  0.5167  0.5119  0.4900  0.5493  0.6490  0.6327  0.5910  0.6020  0.5281  0.5918  - 147 -  T a b l e 2B.  A n a l y s i s o f v a r i a n c e o f mean d a i l y g a i n from start  to  45 Kg  body w e i g h t o f 108 p i g s w i t h  s t a r t i n g w e i g h t as c o v a r i a b l e i n P i g E x p e r i m e n t I  Source  D.F.  Total  S.S.  M.S.  F-value  Variance r a t i o (F nec..) P=0.05  P=0.01  2.35  3.29  107  0.7442  Treatment (a)  5  0.3222  0.0644  Sex  (b)  1  0.0043  0.0043  1.32  3.98  7.01  Block  (c)  2  0.0117  0.0058  1.81  3.13  4.92  5  0.0136  0.0027  0.84  2.35  3.29  10  0.0334  0.0033  1.04  1.97  2.59  2  0.0020  0.0010  0.31  3.13  4.92  10  0.0257  0.0026  0.80  1.97  2.59  1  0.1023  0.1023  3.98  7.01  71  0.2292  0.0032  a x b a x e b x c a x b x c Starting  weight  Residue  **  P < 0.01  19.96**  31.60**  - 148 -  T a b l e 3A.  Mean d a i l y g a i n (Kg) from 45 Kg body v;eight t o finish  Treatment  of  Rep 1  108  pigs i n P i g Experiment I .  Rep 2  Rep 3  Male  Female  Male  Female  Male  Female  0.8002  0.7917  0.6976  0.6345  0.7310  0.7071  0.8257  0.7333  0.6186  0.6964  0.7071  0.6917  0.7619  0.7214  0.6173  0.7738  0.8648  0.7440  0.6372  0.6247  0.4645  0.5125  0.6952  0.6359  0.5434  0.6299  0.6344  0.4283  0.7262  0.5169  0.7083  0.5710  0.5071  0.6368  0.7310  0.6567  0.8129  0.5263  0.5939  0.5656  0.8206  0.5701  0.6797  0.7476  0.6881  0.5015  0.7345  0.5474  0.6750  0.6074  0.5100  0.4710  0.5020  0.5900  0.7993  0.7107  0.8112  0.8248  0.8078  0.6024  0.8112  0.7524  0.7058  0.6632  0.6976  0.7440  0.8197  0.6301  0.7296  0.6883  0.7942  0.8019  0.8112  0.6905  0.7857  0.6494  0.8291  0.7655  0.7631  0.5539  0.7279  0.6463  0.6909  0.6709  0.7369  0.5658  0.5558  0.4408  0.8172  0.6571  0.8070  0.5560  0.6881  0.6395  0.6502  0.7152  0.6048  0.7452  0.7107  0.6845  0.7645  0.6385  0.7039  0.6821  0.7131  0.7131  0.6455  0.6848  - 149 -  T a b l e 3B.  A n a l y s i s o f v a r i a n c e o f mean d a i l y g a i n from 45 Kg body w e i g h t t o f i n i s h  of  108  p i g s w i t h no  c o v a r i a b l e i n P i g Experiment I .  Source  Total  Variance r a t i o (F nec.)  D.F.  S.S.  107  1.0421  M.S.  F-value  P=0.05  P=0.i  Treatment  (a)  5  0.2904  0.0581  10.07**  2.35  3.29  Sex  (b)  1  0.1021  0.1021  17.69**  3.98  7.01  Block  (c)  2  0.0909  0.0455  7.88**  3.13  4.92  5  0.0381  0.0076  1.32  2.35  3.29  10  0.0701  0.0070  1.22  1.97  2.59  2  0.0117  0.0058  1.01  3.13  4.92  a x b x c  10  0.0235  0.0024  0.41  1.97  2.59  Residue  72  0.4153  0.0058  a x b a x e b x c  * P < 0.01  - 150 -  T a b l e 4A.  Mean d a i l y g a i n (Kg) from s t a r t t o f i n i s h o f 108 p i g s i n P i g E x p e r i m e n t I .  Treatment  Rep 1  Rep 2  Rep 3  Male  Female  Male  Female  Male  Female  0.7812  0.7333  0.7026  0.7028  0.7276  0.6957  0.7736  0.7173  0.6194  0.6702  0.6933  0.6411  0.6837  0.7079  0.6446  0.7536  0.6988  0.6995  0.6508  0.5882  0.4897  0.5337  0.5778  0.5548  0.3747  0.5830  0.5344  0.4587  0.6322  0.4993  0.5994  0.5185  0.5627  0.6318  0.5899  0.5774  0.7687  0.4942  0.5903  0.5791  0.7146  0.5521  0.6315  0.6162  0.6409  0.5226  0.6747  0.5739  0.5805  0.5774  0.5197  0.4116  0.5203  0.6088  0.7724  0.6577  0.6775  0.6928  0.7581  0.6077  0.7235  0.6679  0.6607  0.6267  0.7080  0.6850  0.7301  0.5518  0.5795  0.6210  0.7190  0.7203  0.6768  0.6528  0.7141  0.6177  0.6859  0.6852  0.6681  0.5860  0.6098  0.6098  0.6544  0.5603  0.6615  0.5797  0.6038  0.3983  0.6342  0.5995  0.6962  0.5505  0.6533  0.6122  0.6626  0.6412  0.5949  0.6134  0.6231  0.6465  0.6183  0.5973  0.6151  0.6781  0.6796  0.7036  0.5749  0.6381  Table  4B.  A n a l y s i s o f v a r i a n c e o f mean d a i l y g a i n from s t a r t 108 p i g s w i t h  Source  D.F.  to f i n i s h o f  s t a r t i n g weight as c o v a r i a b l e i n P i g Experiment I  S.S.  M.S.  F-value  Variance Ratio F(nec. ) P=0.05  P=0.01  107  0.6734  Treatment (a)  5  0.2772  00.0554  17.549**  2.35  3.29  Sex  (b)  1  0.0306  0.0306  9.688**  3.98  7.01  Block  (c)  2  0.0019  0.0010  0.315  3.13  4.92  5  0.0299  0.0597  1.891  2.35  3.29  10  0.0256  0.0026  0.811  1.97  2.59  2  0.0036  0.0018  0.577  3.13  4.92  10  0.0173  0.0017  0.548  1.97  2.59  1  0.0347  0.0347  3.98  7.01  71  0.2243  0.0032  Total  a x b a x e b x c a x b x c Covariable Residual  10.995**  - 152 -  T a b l e 5A.  Average f e e d c o n v e r s i o n  e f f i c i e n c y r a t i o per p i g  (D.M. f e e d i n t a k e ( k g ) / w e i g h t  g a i n (kg)) i n P i g  Experiment I .  Treatment  Rep 1  Rep 2  Rep 3  1  2.762  2.787  2.943  2  3.414  3.466  3.341  3  3.222  3.289  3.341  4  2.890  2.924  3.040  5  2.971  3.049  3.035  6  2.919  3.048  3.093  T a b l e 5B.  A n a l y s i s o f v a r i a n c e of f e e d c o n v e r s i o n  efficiency  r a t i o i n P i g Experiment I .  Source  Total  D.F.  S.S.  M.S.  17  0.7699  Treatment  5  0.7014  0.1403  Covariable starting weight  1  0.0007  0.0007  11  0.0657  0.0060  Residual  F-value  23.4865**  0.1128  Variance r a t i o F(nec. .) P=0.05  P=0.01  3.20  5.32  4.82  9.65  - 153 -  T a b l e 6A.  T o t a l back f a t  (mm) of 107 p i g s i n P i g E x p e r i m e n t I  Rep 1  Rep 2  Rep 3  Treatment . Male 1  2  3  4  5  Female  Male  Female  Male  Female  91  80  90  82  84  62  96  88  83  81  103  76  87  78  83  84  90  77  104  95  70  93  91*  79  82  100  78  100  95  103  96  104  97  120  108  85  81  97  89  100  109  106  86  120  95  104  87  92  84  109  75  105  92  98  91  104  82  106  95  94  96  99  102  79  85  66  90  95  99  102  81  82  101  64  100  86  87  88  103  75  85  79  97  100  115  55  97  91  86  89  92  86  103  98  81  100  86  95  91  68  94  87  105  83  84  96  101  .  79  •o  6  C a l c u l a t e d m i s s i n g v a l u e (Snedecor and C o c h r a n ,  1967).  .  T a b l e 6B.  A n a l y s i s o f v a r i a n c e o f t o t a l back f a t t h i c k n e s s w i t h f i n a l body w e i g h t , average body w e i g h t g a i n and body l e n g t h as c o v a r i a b l e s i n P i g Experiment I .  Source  D.F.  Total  106  Treatment (a)  5  Sex  (b)  1  Block  (c)  2  a x b a x e b x c a x b x c  S.S.  M.S.  1157.6  P=0.01  656.35 40.553  231.53  3.207**  2.35  3.29  656.35  9.090**  3.98  7.01  20.276  0.281  3.13  4.92  5  358.44  71.687  0.993  2.35  3.29  10  838.37  83.837  1.161  1.97  2.59  2  153.20  76.599  1.061  3.13  4.92  1.648  1.97  2.59  3.98  7.01  0.350  3.98  7.01  7.703**  3.98  7.01  10  1190.0  119.00  1  947.86  974.86  A.D.G.  1  25.24  25.24  Body l e n g t h  1  556.17  556.17  P < 0.01  P=0.05  10860.683  F i n a l body wt.  Residual  F-value  Variance Ratio F(nec. • )  68  4909.9  72.204  13.501**  - 155 -  T a b l e 7A.  Back f a t  40 mm  from mid l i n e (mm)  o f 107 p i g s i n  P i g Experiment I .  Treatment  1  2  3  4  5  6  Rep 2  Rep 1  Rep 3  Male  Female  Male  Female  Male  Female  21  14  16  15  19  12  22  17  16  9  17  12  17  14  20  12  20  9  20  22  12  16  17*  17  13  21  23  11  24  19  20  18  23  21  25  22  18  11  20  16  20  19  23  21  21  20  21  14  14  15  23  12  25  21  16  16  18  14  24  14  23  17  18  17  22  13  20  12  17  17  22  20  15  13  17  13  22  18  15  15  17  15  15  17  15  17  28  6  17  19  17  16  19  14  19  17  13  22  22  21  16  8  22  21  22  16  13  21  C a l c u l a t e d m i s s i n g v a l u e ( S c e d e c o r and C o c h r a n , 1967).  Table  7B.  Analysis of variance  o f back f a t  40 mm  from mid l i n e w i t h  f i n a l body  w e i g h t , average d a i l y weight g a i n and body l e n g t h as c o v a r i a b l e s i n Pig  Experiment I .  D.F.  Source  S.S.  Treatment (a)  5  Sex  (b)  1  48.793  Block  (c)  2  7.407  5  55.658  a x b  154.03  150.61  10  a x e  2.35  3.29  48.793  5.858**  3.98  7.01  0.445 .  3.13  4.92  11.132  1.336  2.35  3.29  15.061  1.808  1.97  2.59  15.075  1.810  3.13  4.92  0.589  1.97  2.59  3.98  7.01  3.98  7.01  3.98  7.01  3.7035  10  49.043  F i n a l body wt.  1  138.575  138.575  A.D.G.  1  21.131  21.131  Body  1  126.343  126.343  x b x c  length  Residual  68  **  * p < 0.05  P=0.01  3.698**  30.150  a  P=0.05  30.807  2  b x c  F-value  1348.190  106  Total  M.S.  Variance Ratio F(nec.)  566.45  P < 0.01  4.9043  8.330  16.636** 2.537 15.167**  - 157 -  T a b l e 8A.  Eye muscle a r e a (mm ) o f 107 p i g s i n P i g Experiment I .  Rep 1  Rep 2  Rep 3  Treatment  *  Male  Female  Male  Female  Male  Female  2430  2900  2700  2650  2750  3080  2510  2830  2960  3200  2750  3660  2550  3060  2690  3220  3080  3440  2190  2680  2560  2820  2333*  2540  2080  2600  2500  2910  2250  2800  2390  2580  2420  2580  2170  2670  2410  3030  2540  2780  2250  2890  2880  2810  2520  2400  2660  3290  2620  2740  2660  2910  2360  2540  2900  2910  2280  2390  2890  2770  2410  2880  2810  3320  2500  2750  2540  2450  2880  2690  2590  2680  2760  3010  2900  2880  2490  2740  3120  3000  2770  2750  2580  1980  2480  2520  2320  2560  2470  2420  2760  2690  2550  2880  2330  3330  2850  2470  2440  2600  2630  3010  2320  2440  2400  2710  2710  2730  C a l c u l a t e d m i s s i n g v a l u e (Snedecor and Cochran, 1967).  Table  8B.  A n a l y s i s of v a r i a n c e o f eye muscle a r e a w i t h d a i l y g a i n and body  106  0.78515  X  io  7  Treatment (a)  5  0.14274  X  10  7  Sex  (b)  1  0.76233  X  io  6  Block  (c)  2  36818.0  5  0.46021  X  io  10  0.93779  X  io  Total  a x b a x e  2  b x c  c  2.35  3.29  0.76233 x 1 0  6  14.842**  3.98  7.01  2.35  3.29  6  93779  1.826  1.97  2.59  35042  0.682  3.13  4.92  26036  0.507  1.97  2.59  1  0.11576  X  io  6  A.D.G.  1  0.22464  X  io  6  Body l e n g t h  1  63524  P < 0.01  5.558**  1.792  F i n a l body wt.  tick  6  92043  6  P < 0.05  0.28547 x i o  6  io  0.11576 x i o  6  2.254  3.98  7.01  0.22464 x i o  6  4.374*  3.98  7.01  1.237  3.98  7.01  63524 X  io  P=0.01  4.92  70083  0.34926  P=0.05  3.13  X  68  Variance Ratio F(nec.• )  0.358  0.26036  Residual  F-value  18409  10  a x b x  average  l e n g t h as c o v a r i a b l e s i n P i g Experiment I .  M.S.  S;.S  D.F.  Source  f i n a l body weight,  7  51361.8  - 159 -  Table 9 A .  Eye muscle i n d e x ( l e n g t h 'A' x w i d t h  'B') (mm ) o f t h e  107 p i g s i n P i g E x p e r i m e n t I .  Treatment  1  2  3  4  5  6  Rep 1  . Rep 2  Rep 3  Male  Female  Male  Female  Male  Female  3195  3927  3696  3840  3840  4717  3750  3840  4345  4592  4056  5187  3476  4312  3854  4536  4480  5162  2982  3871  3483  4050  3254*  3724  3280  3619  3465  3864  3634  3876  3600  3476  3300  3822  3358  3713  3234  4361  3600  4100  3212  4160  4088  3850  3572  3577  3700  4346  3854  3850  3555  3773  3168  3619  4250  4345  3337  3431  4100  3984  3408  4081  4067  4644  3969  4080  3564  3690  4080  3950  3750  3920  3672  4346  4182  4539  3528  3960  4582  4592  3978  4018  4067  3139  3724  3577  3225  3696  3650  3572  4018  3431  4104  3360  4720  3822  3672  3588  3936  3569  4316  3192  3384  3397  3772  3840  3634  3927  .  C a l c u l a t e d m i s s i n g v a l u e (Snedecor and C o c h r a n , 1967).  T a b l e 9B.  A n a l y s i s o f v a r i a n c e o f eye muscle i n d e x ( l e n g t h x w i d t h ) w i t h f i n a l body w e i g h t , average d a i l y g a i n and body l e n g t h as c o v a r i a b l e s  i n Pig  Experiment I .  D.F.  Source  F-value  M.S.  S..S.  Variance Ratio F(nec. ) P=0.05  P=0.01  106  0.17293  X  io  8  Treatment (a)  5  0.31403  X  io  7  0.62807  X  io  6  5.718**  2.35  3.29  Sex  (b)  1  0.17253  X  io  7  0.17253  X  io  7  15.707**  3.98  7.01  Block  (c)  2  0.29667  X  io  6  0.14834  X  io  6  1.351  3.13  4.92  5  0.61179  X  io  6  0.12236  X  10  6  1.114  2.35  3.29  10  0.22437  X  io  7  0.22437  X  io  6  2.043*  1.97  2.59  2  94287  47144  0.429  3.13  4.92  10  0.56122  X  io  6  56122  0.511  1.97  2.59  F i n a l body w t .  1  0.33189  X  io  6  0.33189  X  io  6  3.022  3.98  7.01  A.D.G.  1  0.57957  X  io  6  0.57957  X  io  6  5.276*  3.98  7.01  Body l e n g t h  1  0.23945  X  io  6  0.23945  X  io  6  2.180  3.98  7.01  68  0.74690  io  7  0.10984  X  io  6  Total  a x b a x e b x c a x b x c  Residual *  P < 0.05  **  P < 0.01  - 161 -  T a b l e 1 0 A . Days on t r i a l s o f 1 0 8 p i g s i n P i g Experiment I .  Rep 1  Rep 2  Rep 3  Treatment Male  Female  Male  Female  Male  Female  70  91  98  91  84  98  91  91  119  98  91  105  98  98  119  98  105  98  98  112  140  113  119  119  113  105  140  140  105  119  119  133  119  119  119  119  77  126  98  112  91  133  112  105  112  133  98  119  119  126  140  140  133  105  84  98  112  91  91  105  91  98  105  119  91  105  98  98  110  112  105  91  105  105  105  119  91  98  98  112  112  119  105  105  105  112  119  119  105  105  98  119  98  112  91  105  119  105  112  112  112  112  105  98  105  105  112  105  T a b l e 10B. A n a l y s i s o f v a r i a n c e o f days on t r i a l s w i t h i n i t i a l body w e i g h t as c o v a r i a b l e i n P i g Experiment I .  Source  D.F.  107  Total  S.S.  M.S.  2 .35  3 .29  4 .4332*  3 .98  7 .01  67. 1515  1 .1095  3 .13  4 .92  605. 5736  121. 1147  2 .0011  2 .35  3 .29  10  588. 8364  58. 8836  0 .9729  1 .97  2 .59  2  95.29601  47. 6480  0 .7873  3 .13  4 .92  10'  274. 5964  27. 4596  0 .4537  1 .97  2 .59  1  4620 .856  3 .98  7 .01  71  4297 .144  8072 .284  Sex  (b)  1  268. 3129  268. 3129  Block  (c)  2  134. 3030  5  b x c a x b x  c  Covariable Residual  *P < 0.05  P=0.01  26 .6750**  1614. 457  5  a x e  P=0.05  21601 .74  Treatment (a)  a x b  F-value  Variance Ratio F(nec.)  **P < 0.01  4620. 856 60. 5232  76 .3485**  - 163 -  T a b l e 11A. D.M.  Treatment  Rep 1  f e e d i n t a k e (g)/wk. i n P i g E x p e r i m e n t I I .  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  12580 .375  14140.000  13166. 950  14990 .225  12767 .850  12900.675  2  11212 .620  13109.890  11204. 960  12840 .660  11165 .510  11465.850  3  11478 .130  123821230  11865. 790  13845 .210  12656 .450  13978.210  4  11870 .400  12939.050  12250. 950  14297 .700  11515 .750  12355.900  10855 .400  12309.730  12093. 620  13764 .010  12466 .520  13911.380  12779 .450  14392.600  11454. 800  11752 .350  11735 .550  11350.850  5  .  6  T a b l e 11B. A n a l y s i s o f v a r i a n c e o f D.M.  feed i n t a k e  (g)/wk.  i n P i g Experiment I I .  Source  D.F.  S.S.  M.S.  Variance Ratio F(nec.)  F-value  P=0.05 Total Treatment Residual  35  4.021 x 10  5  8.369 x 1 0  6  1.674 x 1 0  30  3.185 x 1 0  7  1.0615 x 1 0  NS : n o n - s i g n i f i c a n c e  1.577  6  6  NS  2.53  P=0.01  3.70  - 164 -  T a b l e 12 . A n a l y s i s o f v a r i a n c e o f  N  intake  (g)/wk.  i n P i g Experiment I I .  Source  Total Treatment Residual  P < 0.01  D.F.  S.S.  M.S.  35  13290.6  5  120407.6  24081.51  30  12496.99  416.57  F-value  57.81**  Variance Ratio F(nec.) P=0.05  P=0.01  2.53  3.70  - 165 -  T a b l e 13A. P e r c e n t a g e D.M.  Treatment  d i g e s t i b i l i t y i n P i g Experiment I I .  Rep 1  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  79.26  78.91  77.59  76.58  78.41  79.85  2  78.98  75.19  78.41  75.58  80.51  77.86  3  78.07  75.93  78.34  76.04  74.57  74.59  4  79.36  78.96  78.20  77.06  78.22  75.92  5  78.90  77.89  77.65  75.64  77.55  78.08  6  72.70  73.20  79.02  78.96  80.58  78.40  T a b l e 13B, A n a l y s i s o f v a r i a n c e o f d r y m a t t e r d i g e s t i b i l i t y i n p e r c e n t i n P i g Experiment I I .  Source  Total Treatment Residual  D.F.  S.S.  35  127.679  5  16.943  30  110.74  NS : N o n - s i g n i f i c a n c e  M.S.  3.389 3.691  F-value  0.9180  NS  Variance Ratio F(nec.) P=0.05  P=0.01  2.53  3.70  - 166 -  T a b l e 14A. N i t r o g e n r e t e n t i o n (g)/wk. i n P i g E x p e r i m e n t I I .  Treatment  Rep 1  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  129 .70  143 .52  123 .82  115 .01  146 .59  140 .97  2  99 .89  102 .48  79 .86  95 .33  72 .09  77 .00  3  87 .40  91 .74  106 .73  121 .46  103 .43  111 .17  4  109 .65  107 .84  98 .75  120 .17  103 .97  105 .40  5  104 .80  121 .54  103 .81  118 .90  109 .56  128 .29  6  101 .48  115 .68  98 .40  99 .99  105 .82  91 .36  T a b l e 14B. A n a l y s i s o f v a r i a n c e f o r n i t r o g e n r e t e n t i o n i n P i g Experiment I I .  Source  Total Treatment Residual  P < 0.01  D.F.  S.S.  M.S.  35  10351.80  5  6857.99  1371.60  30  3493.81  116.46  F-value  11.7773**  Variance Ratio F(nec.) P=0.05  P=0.01  2.53  3.70  - 167 -  T a b l e 14C. A n a l y s i s o f c o - v a r i a n c e o f n i t r o g e n r e t e n t i o n w i t h f e e d i n t a k e as c o v a r i a b l e i n P i g Experiment I I .  Source  D.F.  Total  S.S.  M.S.  F-value  Variance Ratio F(nec.) P=0.05  P=0.01  35  10351.800  Treatment  5  3818.843  763.769  8.668**  2.55  3.73  Covariable feed i n t a k e  1  938.654  938.654  10.653**  4.18  7.60  29  2555.155  88.109  Residual P < 0.01  T a b l e 14D. A n a l y s i s o f c o - v a r i a n c e  f o r nitrogen retention with  n i t r o g e n i n t a k e as c o v a r i a b l e i n P i g E x p e r i m e n t I I .  Source  Total  D.F.  S .S.  M.S,  F-value  Variance Ratio F(nec.) P=0.05  P=0.01  35  10351.800  Treatment  5  1665.369  333.074  3.3897*  2.55  3.73  Covariable nitrogen intake  1  644.268  644.268  6.5568**  4.18  7.60  29  2849.541  98.260  Residual  P < 0.05  P < 0.01  - 168 -  T a b l e 15A- N i t r o g e n absorbed as a p e r c e n t a g e o f n i t r o g e n i n t a k e i n P i g Experiment I I .  Treatment  Rep 1  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  78.07  78.24  75.99  75.15  75.59  77.61  2  68.89  64.00  68.45  67.92  74.49  70.91  3  69.45  66.20  69.84  68.33  62.22  60.84  4  71.37  71.14  69.87  70.44  68.96  67.67  5  72.74  70.84  69.29  66.76  67.01  70.60  6  59.05  59.91  75.66  74.73  78 08  71.19  T a b l e 15B. A n a l y s i s o f v a r i a n c e f o r n i t r o g e n absorbed as a percentage o f n i t r o g e n i n t a k e i n P i g Experiment I I .  Variance Ratio Source  Total Treatment Residual  **  P < 0.01  D.F.  S.S.  M.S.  F-value  35  891.128  5  369.320  73.864  4.247**  30  521.808  17.394  F(nec.) P=0.05 P=0.01  2.53  3.70  - 169 -  T a b l e 16A. N i t r o g e n  r e t a i n e d as a p e r c e n t a g e o f n i t r o g e n  i n t a k e i n P i g Experiment I I .  Treatment  Rep 1  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  36.65  36.09  33.09  27.16  40.82  38.85  2  50.60  44.39  40.48  42.16  36.67  38.14  3  41.88  40.75  49.47  48.25  44.95  43.74  4  50.83  45.86  44.35  46.25  49.68  46.93  5  53.29  54.50  47.38  47.69  48.51  50.91  6  43.51  44.03  47.06  46.61  49.40  ' 44.10  Table  16B. A n a l y s i s o f v a r i a n c e  f o r n i t r o g e n r e t a i n e d as a  p e r c e n t a g e o f n i t r o g e n i n t a k e i n P i g Experiment I I .  Variance Source  Total Treatment Residual  * P < 0.01  D.F.  S.S.  M.S.  35  1195.433  5  791.771  158.354  30  403.663  13.455  F-value  11.769**  Ratio  F(nec) P=0.05 P=0.01  2.53  3.70  - 170 -  T a b l e 17A. N i t r o g e n r e t a i n e d as a p e r c e n t a g e of• n i t r o g e n absorbed i n P i g E x p e r i m e n t I I .  Treatment  Rep 1  Rep 2  Rep 3  Rep 4  Rep 5  Rep 6  1  46.97  46.12  44.00  36.30  54.00  50.06  2  73.45  69.37  59.13  62.08  49.23  53.79  3  60.30  61.55  70.84  70.61  72.24  71.90  4  71.22  64.46  63.48  65.65  72.04  69.35  5  73.27  76.94  68.39  71.42  72.40  71.11  6  73.67  73.51  62.21  62.37  63.27  61.95  T a b l e 17B. A n a l y s i s o f v a r i a n c e o f n i t r o g e n r e t a i n e d as a p e r c e n t a g e o f n i t r o g e n absorbed i n P i g E x p e r i m e n t I I  Source  Total Treatment Residual  **  P < 0.01  D.F.  S.S.  M.S.  35  3565.118  5  2544.151  508.802  30  1020.967  34.032  F-value  14.951**  Variance Ratio F(nec,.) P=0.05  P=0.01  2.53  3.70  Table 18  A n a l y s i s of covariance f o r average d a i l y gain and feed conversion  efficiency  with i n i t i a l weight and d a i l y feed intake as c o v a r i a b l e s i n Rat Experiments I, I I  Experiment r  _ Source  and I I I .  S q u a r e  M e a n  DF  Average d a i l y week  1  2  Feed e f f i c i e n c y  gain 3  4  overall  1  2  3  4  overall  Treatments  5  2.8962** 1.4948** 0.4414  0.4165  1.1954**  1.4702** 0.8876** 0.3294  0.2658  0.6117**  I n i t i a l weight  1  1.6993** 1.6769*  1.5153  0.4853**  0.8956** 0.7978*  0.0453  0.7881  1.7953*  D a i l y feed i n t a k e  1  5.3272**. 1.1758** 0.2282  0.5174  0.3543  1.7057*  0.1605  0.3204  0.2975  0.0298  I  0.0009  11.9174** 5.'2256** 3.6885** 4.4858* 0.4196  0.0630  28  0.1396  Treatments  11  3.0793** 1.0924** 1.0618** 1.1032** 1.4758**  I n i t i a l weight  1  D a i l y feed i n t a k e  1  0.2499  0.2720  Residual  0.7948** 0.2835  1.9857** 2.4942** 0.3330**  ii  •  Residual  34  0.1932  0.1894  0.2534  1.8036** 0.6671** 0.8411** 1.5654** 0.9539** 0.8460  0.1672  1.5175** 3.7148** 0.1896**  2.8256** 0.0046  0.9732*  7.2121** 0.0990*  0.0293  0.2482  0.1395  0.3732  13.0126** 3.1398** 9.0803** 13.2613** 4.0303** 0.0960  0.0978  0.1093  0.0159  0.9381**  Treatments  9  2.8886** 1.0166** 1.0979** 0.9896*  1.2320**  1.9398** 0.6131** 0.8235** 1.1636  I n i t i a l weight  1  1.0608** 0.2580  0.2132*  2.0862** 0.1295  0.9242** 3.5582*. 0.1446*  D a i l y feed i n t a k e  1  9.8727** 6.2404** 8.2364** 6.6900** 3.9260**  2.9883** 0.4623  1.2065** 3.8612*  0.1020  0.1101  1.5302** 2.4655*  III  Residual  * P  < 0.05  P <  0.01  28  0.1115  0.2091  0.1812  0.3553 .  0.04755  0.1360  0.5217  0.1169* 0.02324  T a b l e 19  A n a l y s i s o f C o v a r i a n c e f o r PER  w i t h i n i t i a l w e i g h t as a  c o v a r i a b l e i n Rat Experiments I , I I  Mean  Source Rat E x p e r i m e n t I  and I I I .  Square  Rat Experiment I I  Rat Experiment I I I PER  PER  PER  Treatment  (5)*  0.4564**  (11)*  0.3021**  (9)*  0.2419**  I n i t i a l weight  (1)*  0.0450  (1)*  0.0807**  (1)*  0.0142  Residual  (29)*  0.0199  (35)*  0.0092  (29)*  0.0479  Degree o f freedom P < 0.01 .  T a b l e 20.  Experi-  Source  A n a l y s i s o f e o v a r l a n e e f o r c a r c a s s c h a r a c t e r i s e s o f r a t s In Rat Experlrcents  S T o t a l carcass protein  Treatments gains  Residual  29  Treatments Average d a l l y  11 gains  Residual  3J  Residual  P < 0.05 P < 0.01  Protein X i n dry carcass  Protein X l n f a t free carcass  Q  U  A  R  E  Total Pat X l n d r y carcass f a t carcass  T o t a l ash  Ash X i n d r y carcass  Ash X i n f a t free carcans  Prqtein»faf.+ash Dry c a r c a s s u t .  144.61**  0.3846  2.1107**  0.3526  146.31  0.2765  5.039 »«  0.5558  0.0448  0.4064  0.1615  0.8599  0.4577  130.78**  105.00**  17.2980  17.3055  31.0380  81.935*  0.1379  163.53**  8.17B7  8.1784  29.392  13.665  1.7171  12.974  15.382  0.1729  46.360**  88.043**  0.1493*  1.2674** •  0.7986**  61.029*  1.2933"  3.3327**  1.0066**  0.1453  12.680  0.0716  0.3530  0.0821  0.8086  2.2518**  7.1153*  3.1826  62.279** 29  Protein retained Protein intakt  26.658*  9.1631** gains  Protein retention  26.670*  84.275**  Treatments Average d a i l y  and l i t .  DP  cent  Average d a l l y  1, I t  1.8261  7.1153* 64.2752** 3.1826  9.2307** 61.609** 1.8490  173.80**  1.62M  85.464**  63,485**  2.8013  C.6210  41.167  0,0000  135.41**  7.1922-  11.350  1.7418  10.894  111.21** 0.0575 6.0226  80.424** 128.11** 11.418  2.3840 0.0227 2.4095  76.464**  116.67**  0.1926*  399.38**  289.25**  0.7570**  10.002  11.492  0.0849  10.8075** 0.3168  . 0.2757  0.4640  0.5970  1.4870*  0.0813  0.2045  1.1074  

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