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Effects of hypertonic sodium chloride injection on body water distribution in Ducks ... Gulls ... and… Ruch, Frank Eugene 1971

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T H E E F F E C T S O F H Y P E R T O N I C SODIUM C H L O R I D E I N J E C T I O N ON BODY W A T E R D ISTR IBUTION IN DUCKS (Anas platyrhynchus), G U L L S (Larus  g laucescens), A N D ROOSTERS (Gallus domesticus) by F r ank E. Ruch, J r . B. A . , Dartmouth Co l lege, 1964 A Thes i s Submitted i n P a r t i a l F u l f i l l m e n t of the Requi rements for the Degree of Ma s t e r of Science i n the Department of Z O O L O G Y We accept this thesis as conforming to the requ i red standard The Un i ve r s i t y of B r i t i s h Co lumbia June, 1971 In p r e s e n t i n g t h i s t h e s i s in p a r t i a l f u l f i l m e n t o f the r e q u i r e m e n t s f o r an advanced deg ree at 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 , I a g r e e t h a t the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r ag ree t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y p u r p o s e s may be g r a n t e d by the Head o f my Department o r by h i s r e p r e s e n t a t i v e s . It i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l not be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . Depa rtment The U n i v e r s i t y o f B r i t i s h Co lumb ia V a n c o u v e r 8, Canada Date <«»vu^ A B S T R A C T Isotope and dye estimates were made of body f l u i d compartment sizes i n White Leghorn roos t e r s , Glaucous-winged gulls, and i n groups of Pekin ducks which were r a i s e d on either f r e s h water or regimes of hypertonic N a C l solution. The gulls and both groups of ducks were observed to have 3 plasma (T-1824 dye) and total body water (H2O) volumes l a r g e r than those 82 of the roosters, whereas the reverse was true for B r space (extra-c e l l u l a r f l u i d ; E C F ) . measurements. Salt fed ducks showed sm a l l e r , but insig n i f i c a n t l y different compartment sizes (% body weights when com-pared to fr e s h water ra i s e d ducks. The effects of an intravenous injection of hypertonic N a C l on the distribution of body water were compared among birds which differed i n their capacity for renal and ext r a - r e n a l salt elimination. In those birds (gulls, salt water ducks, and f r e s h water ducks with functional salt glands) whj.ch exhibited e x t r a - r e n a l salt secretion, the increase i n E C F was significantly greater i n response to the intravenous injection of hypertonic N a C l than in those birds (roosters and non-secreting f r e s h water ducks) which did not u t i l i z e the salt glands. The relative amounts and concentrations of the salt load removed by renal and e x t r a - r e n a l routes of elimination were compared. B i r d s with actively secreting nasal glands voided a major equivalent of the injected N a C l as ( i i i solutions hypertonic to plasma N a C l le v e l s . Renally eliminated N a C l represented a much sm a l l e r portion of the load and was i n a l l cases hypo-22 or isotonic with plasma ion l e v e l s . Isotopically labelled Na CI administered concomitantly with the salt load i n several of the test b i r d s revealed that a large portion of the labelled sodium chloride was removed by the nasal glands and kidneys before there was equilibration of the injected load with extravascular compartments. A p r e l i m i n a r y report i s made on the composition and possible source of an excess eye secretion observed i n the rearing of saline fed P e k i n ducks. The enlarged Harderian glands of these birds were implicated as the source of a f l u i d s e v eral fold hyperkalemic to plasma ion concentrations. The secreted fl u i d was observed to accumulate and encrust the feathers below the inner canthus of the eye. T A B L E OF CONTENTS I P R E F A C E Abstract i i L i s t of Tables i v L i s t of F i g u r e s v Acknowledgements v i II INTRODUCTION 1 HI M A T E R I A L S AND METHODS Source and Maintenance of B i r d s 4 Sampling Procedures -- Plasma, Cl o a c a l F l u i d , N asal Gland Secretion and Eye F l u i d 5 Ion and Isotope A n a l y s i s .' 7 Body Compartment Estimates a) P l a s m a Volume Determinations 9 b) E x t r a c e l l u l a r F l u i d and Total Body Water Determinations 10 Gland Weight Determinations 13 TV R E S U L T S g 2 3 Measurements of T-1824, B r and H2O Spaces a) P l a s m a Volume 14 b) E x t r a c e l l u l a r F l u i d 15 c) Total Body Water . 16 Effects of Hypertonic N a C l Injection on B r ^ and H^O Spaces 16 Sodium E l i m i n a t i o n a) N a s a l Gland Secretion . . 18 b) Cl o a c a l E x c r e t i o n 19 Eye Drip and Gland Weights 20 V DISCUSSION Compartment Volumes i n Non-Stressed B i r d s 22 Responses to Hypertonic N a C l Injection . 24 Desc r i p t i v e and Functional Aspects of Compartment Spaces 28 Sodium E l i m i n a t i o n 33 Eye F l u i d and Gland Weights 34 VI SUMMARY . . . 37 VII R E F E R E N C E S 39 VIII T A B L E S 43 IX FIGURES ° 57 L IST O F T A B L E S T A B L E I Compar i sons of p l a sma volume (T-1824 Space), e x t r a -ce l l u l a r f lu id volume ( B r ^ Space), and tota l body water (H^O Space) i n f r e sh and N a C l (0.483N) water fed Pek i n ducks (Anas platyrhynchos), gul ls (Larus glaucescens), and White Leghorn roos ter s (Gallus domesticus) 43 T A B L E II P l a s m a volumes (T-1824 Space) and ex t r ace l l u l a r f lu id volumes ( B r ^ Space) co r rec ted for body weight and total body water; total body water (H^O Space) co r rec ted for body weight 45 82 3 T A B L E III Changes i n B r and Spaces fol lowing intravenous in ject ion of 0. 2% body weight (v/w) of 5N N a C l 47 T A B L E IV Sodium e l im inat ion v i a c l oaca l f lu id and nasa l gland secret ion fo l lowing intravenous in ject ion of 5N N a C l (0. 2% body weight) i n f re sh and N a C l (0. 483N) water fed ducks (Anas p latyrhynchos), i n Glaucous-winged gulls (Larus  g laucescens), and i n White Leghorn roos te r s (Gallus  domest icus) „ . . 49 T A B L E V E l e c t r o l y t e concentrat ions of s imultaneously sampled c loaca l f l u id , nasa l gland secret ion and p l a sma at i n t e r -vals p r i o r to and fol lowing the in ject ion of 0. 2% body weight (v/w) of 5N N a C l 51 T A B L E VI E l e c t r o l y t e concentrat ions of eye f lu id re la t i ve to p l a sma and spontaneous nasa l gland secret ion i n ducks (Anas  platyrhynchos) r ea red on f r e sh water and N a C l (0. 483N) solution 53 T A B L E VII Absolute and co r rec ted weights of Ha rde r i an glands, nasa l glands, and kidneys f r o m f re sh water and N a C l (0. 483N) water r ea red P e k i n ducks (Anas platyrhynchos) 55 V LIST OF FIGURES F I G U R E 1 Changes i n f l u i d compartment volumes and plasma Na"*" concentration i n response to salt loading i n a fr e s h water fed duck, Anas platyrhynchos, which failed to produce nasal gland secretion 57 F I G U R E 2 Changes i n f l u i d compartment volumes and plasma N a + concentration i n response to salt loading i n a fr e s h water fed duck, Anas platyrhynchos, which demonstrated nasal gland secretion 59 F I G U R E 3 Changes i n f l u i d compartment volumes and plasma Na~*" concentration in.response to salt loading i n a N a C l solution fed duck, Anas platyrhynchos, which demonstrated nasal gland activity 6 l F I G U R E 4 Changes i n f l u i d compartment volumes and plasma Na^ concentration i n response to salt loading i n a Glaucous-winged gul l , L a r us glaucescens, which demonstrated nasal gland activity 63 F I G U R E 5 Changes i n f l u i d compartment volumes and plasma Na^ concentration i n response to salt loading i n a White Leghorn rooster, Gallus domesticus 65 F I G U R E 6 N a s a l gland responses as compared to changes i n E C F volume after intravenous salt loading 6 7 F I G U R E 7 Sodium elimination v i a cloacal and nasal gland routes i n intravenously salt loaded gulls (Larus glaucescens), salt and f r e s h water fed ducks (Anas platyrhynchos), and White Leghorn roosters (Gallus domesticus) 6 9 v i A C K N O W L E D G E M E N T I would l i ke to extend my s incere apprec iat ion for the patience and s k i l l f u l ass i s tance of my wife Susan, together with the guidance and s t imulat ion of my superv i sor , Dr . Maryanne R. Hughes, f r o m the i n -ception through the long te rminat ion of this work. My apprec iat ion also to D r . W i l l i a m Hoar for his c r i t i c a l help in p reparat ion of the manu sc r i and to the staff of the U. B. C. V i v a r i u m for ass i s tance in mainta in ing the an imal s . This work was supported by Nat iona l Science Foundation Grant GB 2963. • . INTRODUCTION Maintenance of osmotic and ionic balance i n response to variations i n the body fluids of higher vertebrates, such as the b i r d , are p r i m a r i l y the function of the kidney. The kidney may, however, be significantly aided i n some forms by various e x t r a - r e n a l excretory routes or by behavioral adaptations. The contributions of these mechanisms to total osmoregulation i n b i r d s have been described i n considerable detail by the work of K n o r r (kidney), Schmidt-Nielsen (salt gland), F a r n e r and Bartholomew (respiratory ^evaporation, diet tolerances, and regulatory behavior), and others. In con-tr a s t to the abundance of information describing the mechanisms and l i m i t s of these physiological processes, the underlying s t i m u l i for regulatory responses accompanying tonic or osmotic changes are less w e l l characterized. Since tolerance and capacity for change are the central factors i n adaptation and homeostatic control, l i m i t a t i o n s i n the size and ionic composition of body fl u i d spaces must be considered as the most fundamental indexes for both the need and extent of osmoregulation. A surfeit of recent information i n this regard has d i r e c t l y implicated changes in e x t r a c e l l u l a r f l u i d (ECF) volumes with the regulation of hormonal output. F o r example, increases i n E C F volume i n dogs stimulate the release.of aldosterone and antidiuretic hormone (Bartter, 1963). A hormonal effect involving E C F volumes has been observed i n roosters i n which the injection of estrogens affected an increase i n E C F volume which was thyroxin r e v e r s i b l e f (2 (Gi lbert, 1963). Other studies which have demonstrated bas ic d iu rna l changes i n E C F volume o f humans and seasonal E C F volume changes in A r c t i c huskies (Hannon and D u r r e r , 1963) further indicate that the s ize of this compartment is a lab i le parameter and as such may w e l l represent an important l ink between osmot ic conditions of the ce l l u l a r m i l i e u and neura l or hormona l t randucers of regulat ion. E x t r a c e l l u l a r f lu id space changes i n b i rd s have also been assoc iated with the in i t ia t ion of nasa l gland act iv i ty i n ducks and seagul ls. Holmes (1965) has reported that sa l t - load ing in ducks resu l ted i n secret ion of nasa l f l u id i n conjunction wi th ma rked inc reases i n p l a sma vo lume. M c F a r l a n d (1964) has measured the m i n i m u m N a C l load requ i red to e l i c i t nasa l gland secret ion i n a va r i e t y of seagulls and has found that the in ject ion of 0. 49 gm N a C l per k i l o g r a m of body weight resu l t ing i n an average p l a sma ion elevat ion of 21 mEq/1 Na"*~ and 30 mEq/1 CI st imulates gland secret ion. Hormona l studies by Ho lmes , P h i l l i p s and But le r (1961) i n wh ich in ject ion of adrena l co r t i co ids (aldosterone and C o r t i s o l ) i n i t i a ted nasa l gland act iv i ty p r i o r to a r i s e i n p l a sma Na^ l e ve l have been used to suggest that nasa l gland s t imulat ion may be affected by these agents. The authors suggest that the hormones are no rma l l y re leased p r i o r to sec ret ion in response to elevated p la sma N a + concentrat ion. Ev idence f r o m dogs and humans, however, has shown that regulat ion of a ldosterone secret ion occurs independently of e x t r ace l l u l a r ion or water concentrat ions, but i s determined instead by chatiges in E C F volume (Bartter et a l . 1956; Ba r t t e r et a l . 1959; B a r t t e r , 1963). (3 The increasing impl icat ions of ECF volume changes as possible s t imul i f o r osmoregulatory reactions point to the potent ia l usefulness of e x t r ace l l u l a r compartment parameters as portents of a var iety of phys io logical responses. The fol lowing study was undertaken for the purpose of character iz ing i n t r a -c e l l u l a r and ex t r a ce l l u l a r body compartment s izes . For the purposes of th i s work ex t r a ce l l u l a r f l u i d (ECF) volume is comprised of the c i r cu l a t i n g plasma and lymph, the i n t e r s t i t i a l f l u i d , and the sequestered f l u i d s with which these f ree l y exchange. I n t r a ce l l u l a r f l u i d is that volume with in c e l l s , which together with the ex t r a ce l l u l a r f l u i d , comprise the tota l body water (TBW). Three avian species were examined for accomodation and change in each compartment fol lowing intravenous i n jec t i on of a hypertonic NaCl so lut ion., A cor re la t ion between ECF compartment change and osmoregulatory function of the kidney and nasal gland was sought in birds which vary in t he i r a b i l i t y (roosters versus g u l l s ) , need (fresh water versus s a l t water fed ducks), and normal potential ( s a l t adapted ducks versus gu l l s ) for regulation by these two mechanisms. A prel iminary report i s also given on observations of an excess eye secretion in s a l t fed ducks. (4 M A T E R I A L S AND METHODS Source and.Maintenance of B i r d s White P e k i n ducks, domesticated f o r m of Anas platyrhynchos, were ob-tained f r o m a c o m m e r c i a l source two days after hatching and were subsequently maintained for five days on "duck grower mash" and an ad l i b i t u m supply of f r e s h tap water. At the end of this p e r i o d the ducks were randomly grouped; one half (30 birds) continued on a f r e s h water regime and the other half had N a C l added to their drinking water at a rate of approximately 4. 0 gm per l i t e r per week to a maximum concentration of 0.483 M N a C l (0. 557 M N a C l = osmotic equivalent of f u l l strength sea water; P r o s s e r and Brown, 1961). These ducks, designated salt ducks, were maintained at this concentration for at least 45 days p r i o r to their use, during which time they had continuous access to feed and saline solutions. A l l ducks were 90 - 100 days of age .and of mature plummage at the time of experimentation. Both groups of ducks were maintained indoors at normal room temperature i n mesh bottom animal pens housing six ducks each. The Glaucous-winged gulls, L a r u s glaucescens, were caught l o c a l l y using smelt injected with approximately 100 mg of sodium pentobarbital (Abbott V e t e r i n a r y Nembutal). Their body weights were comparable to those of six month old bi r d s reported i n other studies on L a r u s glaucescens of the same locale (Holmes et a l . 1 961). They were fed a ground f i s h and cereal (5 base c o m m e r c i a l cat food (Puss'n Boots) and given an ad l i b i t u m supply of f r e s h tap water during the two weeks p r i o r to their use. Housing was pro-vided i n an outdoor cage under natural temperature and light conditions. P l a s m a ion levels and total body weights at the time of the experiments were only slightly below those recorded on the day of the i r capture. Mature White Leghorn r o o s t e r s , Gallus domesticus, were obtained f rom the Department of P o u l t r y Science and were maintained for at least one week i n indoor pens with c o m m e r c i a l chicken feed and fresh tap water ad  l i b i t u m . A l l b i r d s were repeatedly handled during weighings and blood samplings throughout their r e a r i n g i n a manner that approximated the technique used i n experimental conditions. B i r d s were fasted, but permitted access to t h e i r water sources during the twelve hours preceding experimentation. Sampling Procedures - P l a s m a , C l o a c a l F l u i d , N asal Gland Secretion and Eye F l u i d P r i o r to the start of each run a femoral vein was catheterized under l o c a l anesthetic (topical application of 2% P r o c a i n e HC1 + 1:20,000 Epinephrine-Winthrop Laboratories) and P-90 polyethylene tubing inserted to a point i n the upper leg. This catheter served as the sampling and injection route throughout the test period. The degree of contamination resulting f r om introducing and sampling v i a the same catheter was determined by comparison with a b i r d i n which injection and sampling were c a r r i e d out on opposite legs. (6 Dye, ion, and isotope d i lut ion values were comparable to s ingle catheter p reparat ions . To insure against re s idua l contamination, however, a l l syr inges used to inject concentrated standards were f lushed with 1.0 -2. 0 m l of c i r cu la t i ng blood. A hepar in i zed i sotonic sal ine solut ion was used to re tu rn blood to the end of the catheter, thereby reducing dead space between sampl ings. A single catheter was used as the p r e f e r r e d sampl ing technique i n o rder to m i n i m i z e operat ional t rauma and to ma in ta in a more no rma l blood f low to the ex t rem i t i e s . A t sampl ing t ime the hepar in i zed sal ine was withdrawn and a volume of blood (0. 2 ml) pe rm i t ted to d ra in f r o m the catheter before a sample (0. 5 ml) was co l lec ted. B lood samples were taken f r o m each of the b i rd s at regu lar i n te rva l s 2, 4, 8, 16, 30, 60 and 120 minutes after N a C l loading (0. 2% body weight of 5N N a C l solution -v/w), and at in termit tent sampl ing per iods concomitant wi th c l oaca l d i s -charges and nasa l f lu id co l lec t ion i n te r va l s . The tota l blood loss f r o m cannulation and sampl ing dur ing the course of each exper iment i s est imated to have been f r o m 6 to 8 m l . Dupl icate hematocr i t s were taken of each blood sample us ing S t rumia m i c r o h e m a t o c r i t tubes (32 x 0. 8 mm) wh ich we re spun at 3000 r p m in a M o d e l HN International Equipment Company (IEC) centr ifuge for 30 minutes ; p l a sma was obtained f r o m whole blood samples by centr i fugat ion at 6000 r p m for 10 minutes. Dur ing the exper imenta l procedure the b i rd s were p laced i n canvas s l ings and suspended i n f r u i t c rates mod i f ied to mainta in them in an e rect and near ly no rma l standing posture. Their wings were i m m o b i l i z e d on f oam-f (7 covered boards and thei r legs, which protruded f r o m the sling, were secured to m i n i m i z e movement. Clo a c a l samples were collected by p o s i -tioning a large p l a s t i c funnel under their t a i l s and catching spontaneously voided samples i n weighed glass v i a l s . The volume (estimated f r o m weight) and time of c o l l e c t i o n were recorded for each sample. N a s a l gland secretion samples from ducks and gulls were collected with a minimum of evaporation by ins e r t i n g the upper b i l l and nares into weighed glass collecting v i a l s which were afterwards sealed with airtight tops and stored under r e f r i g e r a t i o n for late r analysis. P o s t - s a l t load collections lasting 15-20 minutes each were continued for one to two hours after injection, or u n t i l dripping had ceased. Samples of eye f l u i d (tears) were taken with a micropipette f r o m the inner canthus of the eye immediately after a drop of f l u i d appeared. Ion and Isotope A n a l y s i s The sodium and potas sium concentrations of urine, d r i p , tear, and plasma samples, which had been diluted to analyzable concentrations with glass d i s t i l l e d water and r e f r i g e r a t e d for periods of 24 to 72 hours, were determined with the use of a Z e i s s P F 5 flame photometer. Chloride determinations were made using a Buchler-Cotlove chloride t i t r a t o r . The radioisotopes used i n this experiment [ N a " (2.8 mC/mg Na ); B r (1.23-2.20 mC/mg B r ); and H2O, (1.0 C/mg H + ) ] were obtained f r o m Cambridge Nuclear Corp. , Boston, Mass. Doubly and t r i p l y l a b e l led plasma samples (0. 1 ml) were dissolved i n Bray's solution (15 ml) and counted on a Mark I (8 82 Nuclear of Chicago l i q u i d s c i n t i l l a t i o n spectrometer. High energy B r (B" = 0 . 4 4 Mev.) and Na ( B + = 0. 5 Mev.) disintegrations were counted simultaneously with the same window settings of Channel C while lower energy t r i t i u m disintegrations were measured i n the lower spectrum 22 82 settings on Channel A. Na and B r counts were further separated i n t r i p l y l a b e l l ed samples by recounting after 10 days when the disintegrations of remaining B r were reduced to background le v e l s . . [Half l i f e (t 1/2) B r 8 2 = 35. 7 hours; t 1/2 N a 2 2 = 2. 6 y r s . ; ;t 1/2 H 3 = 12. 5 y r s . ] The 22 82 significance of the overlap of lower energy Na and B r disintegrations into the t r i t i u m spectrum was reduced by maintaining H^O at an approxi-2 2 82 3 m a t e l y ten fold greater concentration. (Na + B r = 1500 cpm; H 2 O = 10,000 cpm). Samples of dr i p , c l o a c a l f l u i d , and standard solutions (0. 01 ml) were quenched to the same degree as blood samples by the addition of 0. 1 m l of unlabelled plasma. Two consecutive one minute counts were made on each sample and the average of these recorded as the f i n a l counts per minute (SD = 1 1 to 2%). Body Compartment Estimates The dilution technique for measuring body compartment sizes i s based on the assumptions: 1) that the t r a c e r substance mixes rapidly and uniformly with the f l u i d and the compartment to be measured, 2) that i t s presence i n no way affects the p h y s i o l o g i c a l state of the compartment or the animal, and 3) that i t remains exclusively i n the domain of the space being measured. (9 a) P l a s m a Volume Determinations. One m i l l i l i t e r of a 1. 0% T-1824 (Evans Blue) dye solution was injected with a calibrated syringe one hour p r i o r to salt loading and blood samples were taken subsequently at 5, 10, and 60 minutes after dye injection. The concentration of the c i r c u l a t i n g dye was determined f rom standards made by diluting aliquots of the concentrate (1. 0% T-1824) with volumes of the animal's plasma obtained 36 hours p r i o r to the experiment. A constant volume of plasma (0. 1 ml) together with varying amounts of dye concentrate were diluted to 2. 0 m l with physiological saline (155. 0 mEq/1 N a C l and 5. 0 mEq/1 KC1) and percent transmittance read on a Bausch and Lomb Spectronic 20 c o l o r i m e t e r at 620 mu. Estimates of the dye con-centration, when mixing had been completed, were made by extrapolating the disappearance rates of the dye to time zero on semilogarithmic plots of concentration (ug/ml) versus time (minutes), according to the method of Dawson e t a h (1920). The volume of c i r c u l a t i n g plasma at time zero was then calculated using the known concentrations of dye before and after m ixing. P l a s m a volume (ml) = ug of T-1824 injected  ug T-1824/ml plasma at time zero C e r t a i n c o rrections are therefore necessary i n evaluating the actual behavior of T-1824. The r a p i d and stoichiometric binding of T-1824 to molecules of serum albumin makes i t a p a r t i c u l a r l y suitable indicator of plasma compartment size, but because of its observed accumulation i n (10 Kvipfer ce l l s and other macrophage centers and the known leakage of p l a sma prote ins into the lymphat ic sys tem, the disappearance rate of T-1824 is s igni f icant and measurab le (Moore et al_. 1943). Since the disappearance rate of T-1824 under re l a t i ve l y unal tered phys io log i ca l conditions has been shown to be f a i r l y constant, co r rec t i on s for i t s loss dur ing the i n i t i a l d i s t r ibut ion pe r i od before m ix ing i s complete may be made by extrapolat ing the slope of the l i nea r por t ion of the loss rate to t ime zero (Dawson et a l . 1920). E s t imates of p l a sma volume using T-1824 have been shown to compare favorably wi th values obtained us ing other methods (I - Se rum A l b u m i n = RISA; Huggins et a l . 1963). P l a s m a samples wh ich gave evidence of hemoly s i s were excluded f r o m c o l o r i m e t r i c determinat ions . b) E x t r a c e l l u l a r F l u i d and Tota l Body Water Determinat ion. A t the 82 start of each exper iment 1.0 - 1.5 m l of a m ix tu re of N a B r (35. 0 pc) 3 and O (5. 0 mc) was sampled i n dupl icate (0. 01 ml) and the remainder injected wi th a ca l i b ra ted syr inge v i a the indwel l ing catheter and al lowed to equ i l ibrate wi th the b i r d ' s ch lo r ide and exchangeable hydrogen spaces. Based on observat ions of equ i l ib rat ion t imes in p i lo t exper iments and in cont ro l b i r d s comparable i n weight to exper imenta l b i r d s , m ix ing of B r ' 3 was complete after 1 . 0 to 1.5 hours and m ix ing of H^O after 1. 5 to 2. 0 hours . E s t imate s of p r e - s a l t load E C F (ext race l lu la r fluid) and T B W (total body water) vo lumes were made on p l a sma samples taken at var ious i n te rva l s after the i n i t i a l m ix i ng pe r i od . The approx imat ion (11 of these volumes based on the distributions of t r a c e r isotopes i n th e i r respective spaces followed the general formulae: E C F : g 2 g 2 g2 (total cpm B r injected) - (total cpm B r excreted B r space (ml) = • i n cloaca l f l u i d and drip) cpm B r per m l plasma sample TBW: 3 • ' (total cpm H -JO injected) - (total cpm excreted H2O space (ml) = i n c l o a c a l f l u i d and drip) 3 cpm H2O per m l plasma sample Blood samples were often taken i n the periods between normally i n f r e -quent and sporadic cloaca l f l u i d collections. To c o r r e c t for t r a c e r loss in u r ine being formed and stored during these i n t e r v a l s i t was assumed that the rate of l o s s , due p r i n c i p a l l y to urine formation (there was no evidence of fecal contamination i n most cases), was constant i n these intervening periods. The total counts per minute (cpm B r or H-,0) l o s t i n urine formed p r i o r to a blood sampling at time " t " , t minutes after the injection of isotopes, was then calculated i n the following manner: + C i + c 0 82 ^ Total cpm (Br or H^O) excreted i n urine formed p r i o r to time " t " after i n -jection of isotopes ( C 7 ) (t2-t!) X (t - t x ) min. min. t = time of blood sampling between cloacal f l u i d excretions C-^  and C2. 82 3 Ci= total cpm (Br or H2O) i n cloacal f l u i d discharge preceding blood sample. 82 3 C2= total cpm (Br or H 2 O ) i n f i r s t c l o a c a l f l u i d discharge given after blood sample. ( 1 2 t j = time at which was collected. - time at which was collected. 8 2 3 C Q = total cpm (Br or H2O) excreted i n cloacal f l u i d p r i o r to discharge at time t^ . 8 2 3 The same procedure was used i n estimating the total cpm (Br or H2O) lost through nasal gland secretion when a given blood sampling occurred 8 2 3 within a drip c o l l e c t i o n i n t e r v a l . The total cpm (Br and H^O) lost at the time of any blood sampling represented the sum of drip and cloacal f l u i d l o sses. Average p r e - s a l t load values for estimates of E C F and TBW i n each b i r d were obtained from multiple plasma samples taken over a pe r i o d of 3 - 5 hours p r i o r to salt injection. Repeated sampling ( 2 - 5 ) during this period between isotope injection and salt loading indicated that the size of these f l u i d spaces remained r e l a t i v e l y con-stant under nonstres.s conditions. The constancy of these spaces was additionally confirmed for periods lasting the duration of an average experiment ( 6 - 7 hours) i n two salt water and two fr e s h water ducks. Because of the short duration of these experiments, during which time 8 2 the predominant movement of B r was assumed to be among extra-8 2 c e l l u l a r spaces, there were no corrections made i n any of the B r space volumes for i n t r a c e l l u l a r equilibrations. Inherent i n a l l group comparisons was the assumption that the presence of this e r r o r was standard throughout treatment and species differences. The changes i n 8 2 B r space volumes have been expressed, for purposes of comparison, (13 the difference between the average p r e - s a l t load volumes and that of the maximum volume observed i n a sixty minute peri o d after salt i n -jection. Estimates of the i n t r a c e l l u l a r f l u i d volume (IGF) during pre-82 and post-load periods were obtained by subtracting B r space f r o m 3 H2O space volumes. In s e v eral of the experiments radioisotopic Na C l (5-15 mC) was mixed with unlabelled N a C l i n preparing the hypertonic load medium. The presence of Na label i n cloaca l f l u i d and nasal drip samples of b i r d s responding to the load provided a comparison of the percentage of N a ^ excreted by these two routes. Gland Weight Determinations A t the completion of the experimental procedure b i r d s were s a c r i f i c e d by decapitation. Harderian glands, nasal glands, and kidneys were removed, tr i m m e d of connective tissue, and weighed to the nearest m i l l i g r a m on a M e t t l e r t o r s i o n balance. Dry weights were obtained by heating tissues to constant weight i n a 150 °C oven for 24 hours and reweighing. Wet and dry weights were compared i n fresh and salt water fed ducks and are reported i n c o r r e c t e d f o r m as gm or mg% body weight. R E S U L T S 82 3 Measurements of T-1824, B r and H2O Spaces a) P l a s m a Volume. Estimates of plasma volume by the Evans blue (T-1824) dye method have resulted i n reproduceable approximations of this compart-ment size which were consistent with previously published determinations for two of the groups tested. Tables I and II indicate the results of measurements for two White Leghorn roosters (x = 4. 4 gm % body weight). Estimates of plasma volume i n f r e s h water reared P e k i n ducks for the control p e r i o d p r i o r to salt loading yielded somewhat l a r g e r volumes (x = 6. 0 + 0. 3%). P l a s m a volume relative to body weight appears to be significantly (p =<0.05) increased i n the group of ducks receiving salt supplemented water (6.5 + 0. 9%) as opposed to f r e s h water ducks (5. 7 + 0 . 5%). Because of the large differences in body weights between saline and f r e s h water fed ducks (Table I) i t appeared more desirable to compare plasma volumes with reference to a standard that was l e s s treatment variant than body weight. Estimates of total body water f r o m space measurements Were less subject to saline effects, as evidenced by the s t a t i s t i c a l l y insignificant (p =<0. 10) c o r r e l a t i o n 3 of H2O space volumes with body weights i n the two groups of ducks (Table I). 3 A comparison of plasma volume as a percentage of the T^O space did not substantiate the difference with respect to body weight seen between f r e s h 3 and salt water ducks (Table II). The use of H^O space i s considered here (15 the more meaningful index for comparison both because of its reduced bias and its general relevance to a l l phases of body fl u i d distributions. In the gulls used i n this experiment, estimates of plasma volume based on body weight and H^O space were x = 7. 16% and x = 8. 14% respectively. These values, l i k e those of the ducks, were considerably l a r g e r than the volumes found i n roosters (see Table II). 82 b) E x t r a c e l l u l a r F l u i d . B r space measurements as approximations of ex t r a c e l l u l a r f l u i d volume l i k e w i s e , were made during the periods p r i o r and subsequent to salt loading i n each of the test groups. Estimates of the size of this compartment i n the various groups were made simultaneously with other isotopic measurements of compartments during the post e q u i l i -b r ation p e r i o d p r i o r to salt loading (1-2 hours after injection). Table I 82 indicates the relative proportions of B r space means and Table II the 82 82 3 B r space: body weight and B r space: H^O space ratios. A comparison 82 of B r space volumes re l a t i v e to body weight (Table II) indicates a some-what l a r g e r volume for this compartment i n gulls. As indexed against 3 individual H^O spaces, however, group differences assume another pattern with the ratios of s a l t w a t e r ducks (41.3%) and gulls (43.6%) being i n t e r -mediate between those of f r e s h w a t e r ducks (36.4%) and roosters (52.9%). The relevance of these two patterns w i l l be discussed late r with reference to possible p h y s i o l o g i c a l implications i n salt loading effects. (16 c) Tota l Body Water. E s t imate s of total body water i n roos te r s (5c = 3 54. 3 gm % body weight) were cons iderably sma l l e r than H2O spaces observed i n the gulls (86.8 and 89. 1%) and s l ight ly sma l l e r than those of e i ther the f re sh water (68. 5%) or salt water ducks (64. 0%). 82 3 Ef fect s of Hyperton ic N a C l Injection on B r and H-,Q Space Vo lumes The nature of equ i l ib rated isotope space responses to intravenous i n -ject ion of hypertonic N a C l are given i n Table III and i l l u s t r a ted i n f igures 82 1-5. When the magnitudes of B r space changes are compared (Table III) a s ign i f icant d i f ference (p =<0. 01) i s observed between the mean inc rease of f r e s h (10. 59%) and salt water ducks (25.49%) which pa r a l l e l s the d i f ference observed i n changes of the roos ter s (16.82%) and gulls (33.09%). The d i f ference between f re sh and salt water ducks i s broadened and a suggestion as to i t s phys io log i ca l s ign i f icance made when the nasa l f lu id secret ing f r e sh water ducks (C - 6#3 and C - 3#3) are grouped with the salt 8 2 fed ducks. The average percent change in B r space of a l l ducks responding to the salt load by secret ion of nasa l gland f l u id (23. 6% ± SE. = 2. 11%) was substant ial ly h igher than those of non- secret ing ducks (5. 1% ± SE. = 1. 55%). 82 * - • A plot of the percent change i n B r space against the volume of co l lected nasa l dr ip (F igure 6) suggests the po s s i b i l i t y that a c r i t i c a l volume change may be assoc iated wi th in i t i a t i on of nasa l gland act i v i ty . There i s no co r r e l a t i on between the magnitude of change and the volume of secret ion as shown in th is f igure. (17 82 3 F i g u r e s 1.-5 depict the time course of changes i n B r space, space, i n t r a c e l l u l a r volume, and plasma N a + concentration for pre- and post-salt load in t e r v a l s i n secreting (Figures 2, 3, 4) and non-seereting (Figure 1,5) f r e s h and s a l t w a t e r ducks, seagulls, and roosters. Although plasma Na"*" levels markedly increased i n a l l of the b i r d s as a result of the hyper-82 tonic N a C l injection, B r space expansions vary f r o m increases of 2. 1 -7. 3% i n fresh water ducks (without nasal secretion) to increases of 18. 5 -38. 1% over p r e - s a l t load volumes i n gulls and ducks with v i s i b l e nasal gland secretion. A l l of the b i r d s i n this last group (Figures 2, 3, and 4) 82 were observed to have B r space increases that o c c u r r e d maximally within 1 0 - 1 5 minutes after injection, thereafter declining to near pre-salt load volumes. A l l of the observed increases represented substantial changes over mean p r e - s a l t load volumes. Hematocrits of blood samples taken throughout the pre- and post-salt 82 load periods were i n general agreement with the patterns of B r space changes, although the extent of these changes did not appear to m i m i c the individual v a r i a t i o n s i n percent change of this space. Sodium E l i m i n a t i o n C o l l e c t i o n of c l o a c a l excretion and nasal drip for p e r i o d of 2 - 3 hours subsequent to salt loading enabled a comparison of the re l a t i v e efficiency of sodium elimination by the various b i r d s . (18 a) N a s a l Gland Secretion. The percentage of injected sodium voided v i a nasal secretion can be seen (Figure 7 and Table IV) to be highest among the gulls (x = 61. 7%) and substantially higher i n salt water ducks (x = 31. 1%) than i n fresh water ducks with active glands (x = 1. 5%). The observed Na~*" concentrations i n the secretions of these three groups are consistent with the most active glands producing the highest concentrations. (Maximum Na^ concentrations: gull = 1020 mEq/1; salt water duck = 844. 5 mEq/1; fr e s h water duck = 587. 9 mEq/1). The percentage of Na"*" eliminated by the nasal gland i n secreting f r e s h water ducks suggests, however, that the p r i n c i p l e difference i s due to the absence or discontinued presence of secretory s t i m u l i i n these f r e s h water b i r d s . The col l e c t i o n of drip with N a + concentrations comparable to those f r o m salt water ducks (600 mEq/1), and the observation of drip i n response to a second salt load at the end of the experiment i n those b i r d s not responding to the i n i t i a l load, confirmed the presence of active or potentially active salt glands i n a l l of the f r e s h water ducks. A comparison of the percentage of injected Na eliminated with the total nasal gland sodium secretion i n actively. seereting ducks and gulls (Table IV) shows that 14 - 16% of the labled sodium injected appears i n the sodium secretion. B a r r i n g the p o s s i b i l i t y of isotope d i s c r i m i n a t i o n , these findings indicate (as i l l u s t r a t e d by salt water duck C - 1#1, Table IV) that the high v. specific a c t i v i t y of Na"*" found i n the nasal secretion (1.6 x 10^ cpm/mEq Na ) relative to that of the injected load (5.8 x 10 cpm/mEq Na ) or relative (19 to the potentially equilibrated B r space volume (1.08 x 10 cpm/mEq Na +) i s the r e s u l t of a rapidly responding concentration mechanism which effectively acts to remove a significant portion of the immediate source of osmotic s t r e s s . (Na content-of B r space estimated f r o m p r e - s a l t load N a + concentration of plasma and measured volume of Br&2 compartment.) b) C l o a c a l E x c r e t i o n . E l i m i n a t i o n of sodium v i a renal mechanisms, as measured i n c l o a c a l discharge samples (Table IV), was the greatest for roosters which l a c k any extra-renal route of elimination. The average results f r o m two b i r d s show that 19% of the injected N a + load was e l i m i -nated cloa c a l l y . The gulls i n comparison, although l e s s dependent on renal excretion, showed a re l a t i v e l y high percentage of c l o a c a l N a + loss (13%) i n contract to both groups of ducks (3%). The maximal concentration of N a C l i n the c l o a c a l discharge of a l l the salt loaded b i r d s was at most only slightly hypertonic to plasma. Table V gives sodium and chloride concentrations for representative examples f r o m each group-for concurrently sampled post-salt load plasma, nasal d r i p , and cloacal f l u i d . The effectiveness of renal mechanisms i n ridding ionic excesses, as seen i n the roosters (R-2, Table IV), compares favorably with the nasal gland 22 i n the percent of injected Na voided f r o m the body (14. 7%). The specific a c t i v i t y of labelled sodium i n this f l u i d (0. 59 x 10^ cpm/mEq N a + ) , as com-pared to that of the o r i g i n a l salt load (1. 77 x 10^ cpm/mEq Na+) and that of 82 S 4-the potentially equilibrated B r space volume (0.41 x 10 cpm/mEq Na + ) , (20 also indicates an effective removal probably v i a a d i u r e t i c - l i k e response. The l a r g e r volumes and lower urine concentrations (93.3 - 112.8 m E q l / Na +) underscore the relative inefficiency of this mechanism for conserving body water. The renal response of the non-secreting fresh water duck (C - 6#5; Table IV) i s seen to be comparable to that of the rooster i n the N a + con-centration of the collected cloacal f l u i d (77. 1 - 107. 0 mEq/1). Comparable 22 too were the specific activity proportions of their renally excreted Na (1.20 x 10 5 cpm/m Na +) rela t i v e to the N a 2 2 injected (5. 04 x 10 5 cpm/mEq Na +) 22 5 + and the potentially equilibrated e x t r a c e l l u l a r Na (1. 04 x 10 cpm/mEq Na +). 22 The concurrence of higher specific a c t i v i t i e s of Na i n extruded fluids f r om both routes of elimination as compared to potentially equilibrated extra-c e l l u l a r sodium, indicates that both mechanisms are actively removing 82 sodium before the injected load has equilibrated with the B r space. Eye D r i p and Gland Weights The observation of moist feather patches radiating f r o m the anterior corner of the eye into the region below the nasal canthus i n salt water fed ducks (Figure 8) promoted a p r e l i m i n a r y examination into the source and ionic composition of the accumulating f l u i d . Table VI reveals that the cationic composition of samples taken d i r e c t l y f r o m steadily accumulating r e s e v o i r s i n the inner corner i s slightly hypertonic with respect to plasma Na"*", 'but several fold hypertonic to plasma K"^  concentrations. The tear, nasal d r i p , and plasma samples analyzed and presented i n this table were taken f r o m b i r d s p r i o r to their use i n the isotope studies. Accumulations of widely (21 i n termi t tant and overf lowing t e a r - l i k e secret ions , which encrusted the feathers were observed only among ducks given salt water for dr ink ing. Samples of tear s of f re sh water ducks d i sp layed s i m i l a r ion ic compos i t ions. A further examinat ion into the source of this f lu id f r o m the eye of salt water ducks revea led a noticeable hypertrophy of the Ha rde r i an or H a r d e r ' s gland. Table VII presents a compar i son of the absolute and co r rec ted wet and dry weights of these glands, and prov ides a contrast ing compar i son of salt diet effects on kidney and salt gland weights. The wet and dry weights of salt glands were observed to inc rease i n response to continuous high salt intake, and appear i n agreement wi th p rev ious l y documented i nc reases reported for glands i n both ducks and seagulls (Benson and P h i l l i p s 1964; Ho lmes , But t le r and P h i l l i p s 1961). The co r rec ted weights of Ha rde r i an glands were a lso observed to be s ign i f icant ly (p =<0.001) l a r g e r i n salt fed b i rd s whi le there was no apparent t reatment effect on co r rec ted kidney s ize ( p =<0. 15). DISCUSSION Compartment Volumes i n Non-Stressed B i r d s 82 3 A comparison of the p r e - s a l t load sizes of B r , H^O and T-1824 spaces among the three types of birds tested indicates that relative to body weight the volumes for these spaces are noticeably l a r g e r i n ducks and gulls than i n roosters. Support for the observed differences in plasma volume i s given by the consistency of the data in Tables I and II and pre-viousl y published determinations for two of the groups tested. Measure-ments i n two White Leghorn roosters (x = 4. 4 gm % body weight) appear i n agreement with determinations reported by Bond and G i l b e r t (1958) for comparably sized b i r d s ( 3 . 1 ± 0 . 4 % ) . S i m i l a r l y , values for f r e s h water reared P e k i n ducks (x = 6.=}= 0 . 3 gm % body weight) l a r g e l y sub-stantiate those of Portman et_al_. (1952) for White P e k i n ducks of the same size (x = 5. 5 4: 0 . 12%). Although there are presently no other published estimates of plasma volume i n gulls the reported percent body weight (x = 7 . 1 6 % ) agrees closely with s i m i l a r measurements on other species frequenting marine environments such as the redhead and canvasback ducks ( 7 . 1 4= 0 . 2 % ; Bond and Gi l b e r t , 1958). The distinct differences i n plasma volume-body weight proportions observed between roosters on one hand and ducks and gulls on the other, corroborate the findings of Bond and Gi l b e r t (1958) which showed a comparable difference between a large v a r i e t y of aquatic and nonaquatic b i r d s . ( 2 3 In an invest igat ion of the s t r uc tu ra l and functional adaptations of div ing ducks, Bond and G i l be r t (1958) have shown that the p r i n c i p a l d i f ference i n oxygen ca r r y i ng capacity between aquatic b i r d s , which commonly have functional nasa l glands, and non-aquatic b i r d s , which either lack or have : atrophied glands, i s a substant ia l ly l a r ge r blood volume (greater number of red blood ce l l s and greater p l a sma volume) in the f o r m e r . The blood volumes % body weight observed i n this study for f re sh water ducks (10.6%), gul ls (14.6%), and roos te r s (8.1%) are consistent with the p r e -v ious ly mentioned p l a sma volume d i f ferences , and together support the observat ions of Bond and G i l be r t . The addit ional f inding that greater va scu la r vo lumes i n the aquatic b i r d s are accompanied by greater tota l body water may indicate other functional s ign i f icances for the greater ava i l ab i l i t y of body water . The presence of a l a r g e r volume of body water re la t i ve to total body mass would prov ide the advantage of a greater ab i l i ty to withstand dehydrating conditions or sudden ex t r a ce l l u l a r osmot ic i nc rea se s . Bond and G i l be r t have shown that there i s a greater va scu la r volume among b i rd s that are stronger f l i e r s , wh ich i s c ha r ac te r i s t i c of most aquatic species. The presence of l a r g e r H^O spaces in conjunction with i nc reased p l a sma volumes could w e l l function to compensate for l a rge evaporat ive los ses i n c u r r e d during i nc reased phy s i ca l act iv i ty or to m i n i m i z e ion ic changes in e x t r a ce l l u l a r f lu ids resu l t ing f r o m the ingest ion of hypertonic food or dr ink. The hypertonic sec re to ry capacity (24 of the nasal glands could also serve as an adaptation p a r t i c u l a r l y suited for ion regulation under dehydrating conditions such as prolonged flight or the ingestion of sea water. Response to Hypertonic N a C l Injection An equivalent amount of N a C l per unit body weight injected into seagulls, f r e s h and salt water ducks, and roosters produced noticeable differences 82 i n the extent of B r space change and i n the amount of sodium eliminated by each group. The response of the roosters was marked by a l a r g e r i n -8 2 flux of water into the e x t r a c e l l u l a r B r space followed by renal f i l t r a t i o n of about 20% of the salt load. F r e s h water ducks (C-3#6 and C-3#l), i n contrast, demonstrated a greater capacity to absorb this load without 8 2 intercompartmental water fluxes. The magnitude of B r space changes observed i n post-salt load gulls, salt water ducks and secreting f r e s h water ducks closely resembled the response of the roosters. In a l l of these b i r d s which exhibited a greater r e d i s t r i b u t i o n of body water 8 2 and an increase i n e x t r a c e l l u l a r volume the changes i n B r space appeared to p a r a l l e l the onset of osmoregulatory ac t i v i t y . Although no attempt was made to establish the relationship or temporal sequence of secretion or excretion and compartment changes, i t would appear reasonable that the function of spec i a l i z e d osmoregulatory organs may re f l e c t a l i m i t of acom-modation to osmotic changes on the part of the organism. The more energy conservative process of body water redistribution may correlate with the (25 organisms a b i l i t y to respond to osmotic stress by renal and extrarenal mechanisms. If so, a maximum in intercompartmental accommodation might be predicted to precede the specialized functioning of nasal glands and kidneys. The occurrence of significantly l a r g e r dilutions of extra-c e l l u l a r volume i n those b i r d s which responded to the injected load by these mechanisms supports this idea. The greater capacity of non-secreting f r e s h water ducks to absorb the salt load without secretion or elimination i s further evident i n post-salt load plasma sodium measurements. Inspite of the retention of a major portion of the salt load fresh water ducks, without nasal gland secretion, showed a sm a l l e r average increase i n plasma sodium concentration (32 mEq/1) than did secreting f r e s h w a t e r ducks (41 mEq/1) or s a l t w a t e r ducks (45 mEq/1). Lower post-salt load levels of plasma Na"*" together with reduced expansion of the e x t r a c e l l u l a r space suggest a more rapid and complete dis t r i b u t i o n of the injected load i n these b i r d s . The disappearance of injected sodium f r o m the vascular space into i n t e r s t i t i a l , lymphatic and i n t r a c e l l u l a r spaces, i n 82 the absence of a net flow of body water into the e x t r a c e l l u l a r (Br ) space, would suggest a greater a b i l i t y of the c e l l mass of non-secreting f r e s h water ducks to absorb an increase i n sodium concentration. Since neither relative body water, compartment sizes nor plasma N a + and concentrations appeared significantly different between the fresh and salt water ducks, i t would seem that the differences i n compartment responses were not due to salt load effects on these parameters. Individual or species (26 response di f ferences observed in these studies might a l so be due to v a r i -ables which include dehydrat ion to lerance, exc re to ry capacity or threshold and hormona l state. Although the above observat ions might serve to imp l i ca te E C F volume in-creases in nasa l gland secret ion, the exact nature of the st imulus which t r i gge r s secret ion by the salt gland rema ins unreso lved. The o r i g i na l descr ipt ions of the nasa l gland as a s igni f icant osmoregu latory organ in a va r i e ty of mar i ne b i rd s by K. Schmidt -Kn ie l son and co -worke r s (1958) revea led that secret ion can be induced by non-specif ic inc reases in p l a sma osmot ic concentrat ion and that neuronal s t imulat ion proceeds v i a p a r a -sympathetic ennervat ion. Endocr ine studies by Holmes et a l . (1961) have shown that ob l i terat ion of the ex t ra rena l response in adrena lectomized ducks could be reve r sed by the inject ion of Cortisol, cor t i cos terone, cortexone, or aldosterone p r i o r to salt loading. F u r t h e r m o r e , i t was shown that a d m i n i -st rat ion of any of the above hormones or adr enocort icotrophic hormone (ACTH) p r i o r to salt loading in n o rma l b i rd s resu l ted in i nc reases in the i n i t i a l f low rate, vo lume, and N a + and K + concentrations of the d r ip . A l -though there was no demonstrat ion of a d i r ec t effect of these endocrines on gland act iv i ty , the i r presence was establ i shed as neces sa ry for some un -defined sequence of events leading to nasa l secret ion. In a b r i e f desc r ip t ion of the resu lts f r o m an undetai led exper iment, Ho lmes (1965) reported measur ing an i nc rease in blood volume p r i o r to the in i t ia t ion of secret ion in a salt-loaded duck. Injection of an equal volume of gum arable was also (27 reported to have st imulated secret ion. Ho lmes concluded that a volume receptor rather than a ba ro receptor or osmoreceptor par t i c ipates i n the st imulat ing mechan i sm. M o r e recent ly Ha j ja r et_ aL (1970) invest igated the s ignif icance of o smo-l a r i t y i n the s t imulat ion of secret ion in wes te rn gulls (Larus occ identa l i s ) . The i r f indings ind icated that only hypertonic intravenous infus ions (5% N a C l , 27 .5% sucrose, 10% mannitol) were effect ive in e l i c i t i ng secret ion, and no secret ion was produced with e ither hyp o tonic sodium solutions or hypotonic blood volume expansion (6% Dextran 70 i n 0. 9% NaC l ) . S i m i l a r conclus ions were reached by A sh (1969) work ing wi th Ay l e sbu r y ducks. Adm in i s t r a t i on of hypertonic sucrose, mann i to l , or suff ic ient N a C l to r a i s e p l a sma o smo la r i t y 2-8%. e l i c i t ed secret ion i n these b i r d s . Since i n t r a -venous in ject ion of hypertonic KC1, u rea , or dextrose fa i led to evoke secret ion A sh concludes that pe rmeab i l i t y of the hypertonic solute i s also important i n the sec retory mechan i sm. Although there are present ly no explanations that l ink endocr ine, osmot ic , and other factors to nasa l gland secret ion , there is evidence which appears to offer a p laus ib le connection which bears on the resu l t s of this study. Expe r iment s with dogs have shown that i nc reases i n e x t r a ce l l u l a r f lu id volume produced by i soton ic expansion of the space st imulate the re lease of ant id iuret ic hormone (ADH) and aldosterone which function to conserve u r i n a r y water and sodium lo s ses and further augment expansion of the (28 ex t r a ce l l u l a r volume (Bar t ter , 1963). The s t imulat ion of adrenal act iv i ty might a lso lead to i nd i rec t effects on E C F volume such as that produced by co r t i co id s , l i ke cort i sone, which has been shown to i nc rease p l a sma volume and the ex t r a ce l l u l a r space i n humans (Bar t ter , 1963). The presence of volume or s t retch receptors wh ich would moni tor ex t r ace l l u l a r space changes could serve as the t ransducers of osmot ic and neura l s t imu l i for nasa l gland and other compensatory mechan i sms . .Although the report by Ho lmes of secret ion accompanying va scu la r volume change constitutes the only prev ious evidence for a vo lume type receptor , the coincidence of 82 a la rge B r space volume change with the presence of nasa l gland act iv i ty i n this study lends further support to the notion of such a receptor . H e m a -t o c r i t changes, as p rev ious l y mentioned, appeared unre lated to gland act iv i ty in i t i a ted by salt loading. This would suggest that receptor s , i f present, are respons ive to ex t ravascu la r volume change. De sc r i p t i ve and Funct ional. Aspects of Compartment Spaces C r i t i c a l to in terpretat ion of the s igni f icance of t r a ce r d i lut ion spaces i s both the nature of the volume penetrated by the m a r k e r substance and the r e l e -vance of this space to the s ize and behavior of the intended body compartment. The conceptual ized d iv i s ions of body f lu id spaces into i n t r a ce l l u l a r and e x t r a -ce l l u l a r compartments wh ich def in i t iona l ly d i s t inguish i n t r a ce l l u l a r water content f r o m that of the c i r cu la t i ng and rap id ly exchanging intra-i.and e x t r a -va scu la r spaces, have been d i f f i cu l t pa ramete r s to define accurate ly by exper imenta l methods. The absence of t r a c e r substances which are l i m i t e d (29 to the domain of any one compartment or subcompartment, and inab i l i ty to accurate ly measure the e r r o r contr ibuted by impenet rab i l i t y , metabol ic degradation, or non- spec i f i c binding r ema in the p r i n c i p a l d i f f i cu l t ie s of the t r a ce r technique. E s t imate s of tota l body water , f r o m the d i lut ion space of t r i t i u m oxide, have been demonstrated to be among the most re l i ab le of the t r a ce r methods. Re id et a l . (1958) have compared water content of rabbits as measured by t r i t i u m oxide, ant ipyrene, and N-acety l -4 -aminoant ipyrene d i lut ion and have demonstrated coeff ic ients of co r re l a t i on approaching unity for each (0. 98, 0. 99, 0. 99 respect ive ly) when compared to est imates by dess icat ion. The p r i n c i p a l e r r o r s of H^O est imates l i e i n t r i t i u m exchanges with hydrogens other than those of water , and equ i l ib ra t ion with o smot ica l l y i so lated i n te s -t i na l water. The exchange of t r i t i u m for hydrogen i n hydrocarbons and other hydrogenated compounds has been shown to be a re l a t i ve l y slow process i n compar i son to body water d i lut ion, and has been attr ibuted to account for a 0. 5 - 2. 0% ove r -e s t imat i on of this space re la t i ve to body weight i n humans. 3 (Prent ice et a l . 1952). H^O has been shown also to exchange with gut water . B i d i r e c t i o na l measurements have shown this exchange to be an i r r e g u l a r fo rced - f l ow l i k e p roces s with complete l abe l l i ng of in tes t ina l f lu id taking somewhat longer than that of the i n t r a ce l l u l a r and ex t r ace l l u l a r volumes (V i s scher et a l . 1944). The genera l r e l i ab i l i t y of t r i t i u m measurements are further substantiated by the s i m i l a r i t y of total body water est imates for roosters in these exper iments (54. 3% body weight) and those reported by (30 Medway and K a r e (1959; 53. 3% body weight) using antipyrene, a t r a ce r substance which has been shown by others to y i e l d near ly ident i ca l e s t i -mates. 3 The substantial ly d i f ferent t ^ O spaces among the three b i rd s measured may i n part be due to equ i l ib ra t ion d i f ferences mentioned above or to d i f ferences i n the proport ions and types of body t i s sues , but other evidence ind icates a fundamental d i f ference i n this pa rameter among the three species tested. Support for this conclus ion comes f r o m the average hematocr i t s (Table III) which, for a l l the b i rd s rece iv ing f re sh water , appeared i n close agreement with p rev ious l y publ ished averages for comparable s ized roos te r s (45.0 4= 2.0%; Sturk ie, 1965), ducks (43. 0 % 2.0%; Bond and^Gilbert, 1958), and gulls (46. 0 4= 1.2%; Hughes, 1970). Th i s would tend to discount the po s s i b i l i t y of any major d i f ferences i n the i r states of hydrat ion, at least 3 to the extent neces sa ry to account for the re l a t i ve l y la rge H2O space v a r i -ances. Ev idence too, of the rep roduc ib i l i t y of the technique- and the agreement of i t s resu l t s i n one case wi th those of other invest igators mentioned above, fur ther strengthen this conc lus ion. The ins ign i f icant, but consistent. 3 d i f ferences between H2O space as a percent of body.weight i n f r e sh and salt water ducks (Table I) probably re f l ec t a dehydrating effect coupled to a st ress induced storage-t i s sue def ic i t resu l t ing f r o m inc rea sed N a C l intake (K r i s ta et a l . 1961; Ho lmes et a l . 1961). (31 The nature of the calculated i n t r a c e l l u l a r f l u i d volume decrease which closely m i r r o r e d the increase of the B r ^ space suggests a p r e c u r s o r -product relationship which i s consistent with known properties of animal tissues for regulating osmotic e q u i l i b r i u m through shifts i n i n t r a c e l l u l a r ions and/or water. The r e c i p r o c a l relationship between these two changes 3 reflects what can be seen i n Table III to be a r e l a t i v e l y unaffected O space response to osmotic st r e s s . The fluctuations and generally s m a l l 3 increases i n H2O space following salt injection are thought to ref l e c t either 3 the e r r o r inherent i n the technique (SE = 2. 3 to 4. 1% for space measure-ments i n control ducks without salt loads), or possible shifts of body water f r o m more slowly labelled compartments, such as the i n t e s t i n a l tract, which would serve to dilute the pre- e x i s t i n g isotope space. The 1.0 - 1.5 hours permitted for equilibration of t r i t i u m l a b e l i n animals of this size was thought sufficient for exchange with most physiological water since s i m i l a r l a b e l l i n g studies have shown that 1-2 hours produces uniform label l i n g of body water i n humans (Moore et a l . 1963). L i t t l e information 3 exists, however, on the equilibration rate of H2O with anatomically sequestered water such as that of the stomach, bladder, or intestine. The use of t r a c e r substances to measure accurately e x t r a c e l l u l a r water volume has been hampered both by the la c k of a t r a c e r with sufficient s p e c i f i c i t y for this volume, and by uncertainties about the functional and anatomical boundaries of this space. The definition of e x t r a c e l l u l a r space as described by B e r n a r d (1920) and more recently by Manery (1954) (32 subdivides this space into c i r cu la t i ng f lu ids (blood and lymph) and stat ionary f lu ids ( i n te r s t i t i a l , ce rebro sp ina l , p l eu r a l , p e r i c a r d i a l , p e r i -toneal and synov ia l f lu ids , and aqueous and v i t reous humor). The phys io -l o g i c a l s ignif icance of these subdiv is ions for the ex t r a ce l l u l a r storage, exchange and movement of ions and water i s l a r ge l y unknown. Methods for measur ing total e x t r a ce l l u l a r space include substances such as suc -rose and i nu l i n wh ich because of the i r s ize are slow to diffuse with the resu l t that equ i l i b r i um t imes are long and thereby est imates are subject to e r r o r s of excret ion and metabo l i sm. The sma l l e r substances of t h i o -sulfate and radiosu l fate diffuse mo re rap id ly , but are act ive ly metabo l i zed by the k idneys. Since they l ack compartmenta l se lect iv i ty and the fu l l extent of the i r equ i l ib rat ion i s unknown, use of these substances i s of questionable s ign i f icance (Berson and Ya low, 1955). The radioisotopes N a ^ and B r 8 2 appear to be more re l i ab le i n these regards since both are rap id ly d i f fus ing species wi th l a r ge l y e x t r a ce l l u l a r domains dur ing the t ime of the i r equ i l ib rat ion and both are only no rma l l y excreted. The ove r -es t imat ion of E C F volumes by these ions due to exchange with i n t r a c e l l u l a r sodium or ch lo r ide have been found to be measurab le by simultaneous 24 measurements of red blood c e l l penetrat ion. These co r rec ted Na and 82 B r e x t r a ce l l u l a r space est imates in humans (18 - 26% body weight) appear i n genera l agreement with the lengthier i nu l i n measurements (13 - 19% body weight; Rov.ner and Conn, 1963). E C F volume est imates for roosters (28.8% 8 2 body weight) obtained by the B r method in these studies agreed with resu l t s of the thiocyanate method i n White Leghorn, chickens (26. 2%) as determined by Medway and K a r e (1959). (33 8 2 The nature of the B r space changes observed i n these exper iments are thought to represent a predominance of d i lut ion by i n t r a c e l l u l a r water but 82 may a lso re f l ec t an in f lux of B r under rap id ly changing osmot ic condit ions. There were no attempts to measure red blood c e l l permeat ion under var ious exper imenta l condit ions. The demonstrat ion of a rap id and measurab le 82 change i n B r space i n response to osmot ic s t re s s , however, i l l u s t r a te s the s igni f icance of i on and water movement in accommodat ion to sudden osmot ic change. A pos s ib le s ign i f icance for this volume change as a p r e -d i c to r of regu latory responses or as an ind icator of the osmot ic state of the o rgan i sm appears worthy of further examinat ion. Sodium E l i m i n a t i o n The observat ion of mo re act ive nasa l glands producing a highly concentrated secretion i n gul ls i s cons istent w i th publ i shed data which indicates this same const i tu i t ive super io r i t y i n glands f r o m a va r i e ty of gul ls (Schmidt-N i e l s en , 1964) as compared to e i ther w i l d M a l l a r d or domest icated P e k i n ducks ( Schmidt -N ie l sen and K i m , 1964). The l a rge d i f ferences observed between tota l na sa l gland N a + sec ret ion i n f re sh and salt water ducks (Table IV) can be attr ibuted i n part to a volume d i f ference resu l t ing f r o m what has been demonstrated to be a state of glandular hypertrophy i n salt acc l imated ducks (Benson and P h i l l i p s , 1964). The negative response to the salt load witnessed in a number of f resh water ducks as we l l as the s m a l l percentage of N a e l im inated by the nasa l gland in the remainder of this group suggest, however, that the p r i n c i p l e d i f ference i s due to the absence or cessat ion of (34 secretory s t i m u l i i n these fresh water'birds. The collec t i o n of drip with N a + concentrations comparable to those f rom s a l t w a t e r ducks (600 mEq/1), and the observation of drip i n response to a second salt load at the end of the experiment in those birds not responding to the i n i t i a l load, confirmed the presence of active or potentially active salt glands i n a l l of the f r e s h water ducks. Renal elimination of the injected sodium appeared to be a far less efficient mechanism for maintaining body water while removing excess salt i n ducks and gulls. Table V reports post-salt load i n concentrations for plasma nasal gland secretion, and cloacal f l u i d in representative b i r d s f r o m each group. The hypotonic cloaca l f l u i d sodium concentrations under conditions of highly elevated plasma Na"^ levels (Figures 1 - 5), are consistent with previous unsuccessful efforts by Douglas (1970) and Hughes (1970) to ob-tain the significantly hypertonic urine N a + concentrations which are reportedly possible for the duck (600 mEq/1) and gull (300 mEq/1) kidneys (Holmes et a l . 1961). The re l a t i v e l y low percentage of injected sodium which was either secreted or excreted by fr e s h water ducks, as opposed to the other three groups of b i r d s , c l e a r l y repre'sents a greater capacity to redistribute this osmotic load and to accommodate through intercom-pa rtmental change. E y e - F l u i d and Gland Weights The observation reported here of the accumulation of hyperkalemic f l u i d i n the eye region of ducks which had been acclimated to high salt intake, (35 offers the interesting p o s s i b i l i t y that this f l u i d may be a product of active ion elimination. Although the conditions under which the secretion was observed did not permit distinguishing this as a controlled physiological response the injection of hypertonic N a C l was observed to increase the amount of f l u i d present i n the inner canthus. Such secretion could also be a nonspecific cholinergic response i n conjunction with increased para-sympathetic stimulation of the nasal glands. The accumulating f l u i d i n -duced by salt injection was observed to f a l l free of the eye i n the gulls and fresh water ducks onto feathers which appeared w e l l oiled and water repellent. Accumulations i n the eyes of saline fed ducks appeared, i n contrast, to drain into the surrounding feather region. Prolonged secretion of this fluid which is 5 - 25 times more concentrated than plasma K + could result i n a significant elimination of this ion. Attempts to identify the source of this secretion have implicated the H arderian gland, which is increased i n size i n birds exhibiting exterior accumulations of d r i e d f l u i d . P r e l i m i n a r y investigations by Hughes (un-published observations) has revealed a large duct which extends from this gland dorsad along the orbit and opens immediately above the eyeball. Although the coincidence of l a r g e r H a r d e r i a n glands i n the salt fed ducks can only be considered c i r c u m s t a n t i a l evidence for their association with excess eye f l u i d , the presence of these glands as the only conspicuously altered tissues of that region i n salt water fed ducks warrants future (36 confirming investigation. H i s t o l o g i c a l staining of tissues f r o m salt and fresh water ducks has shown that ducts and apocrine c e l l s f r o m the enlar glands are r i c h e r i n alkaline phosphatase. Each of these observations i s presented only as p r e l i m i n a r y evidence from work secondary to the aims of this study. SUMMARY Estimates of plasma volume, e x t r a c e l l u l a r fl u i d (ECF) volume and total body water (TBW) i n f r e s h and N a C l water reared P e k i n ducks, Glaucous-winged gulls, and White Leghorn roosters revealed greater plasma volumes relative to both total body water and body weight i n ducks and gulls. E x t r a c e l l u l a r fluid volume estimates revealed sub-stantially l a r g e r spaces relative to total body water i n roosters as opposed to gulls and ducks. In contrast, TBW was considerably l a r g e r i n ducks and gulls as opposed to roosters. Saline feeding produced no significant differences i n compartment sizes relative to body weight or TBW i n P e k i n ducks. Generally l a r g e r average plasma volumes and lower hematocrits, however, were observed i n N a C l reared ducks. The effects of an intravenous injection of hypertonic N a C l solution were observed on the intercompartmental di s t r i b u t i o n of body water. Expansion of the e x t r a c e l l u l a r space i n response to salt loading was seen to be greatest in gulls, salt a c c l i m i t i z e d ducks, and fresh water ducks exhibiting nasal gland activity. F r e s h water reared ducks generally showed a greater tolerance for hypertonic N a C l loading as evidence by a s m a l l e r change i n E C F volume and l i t t l e or no nasal gland or kidney elimination of the load. In contrast, saline fed ducks (38 exhibited marked changes i n E C F volume spaces together with sizable amounts of nasal drip after salt loading. The nature of this response closely resembled those of the gulls. Redistribution of total body water i s implicated as part of osmoregulatory s t i m u l i . 3. The extent of sodium removal by nasal glands and kidneys i s com-pared among birds receiving salt loads. The salt ducks and gulls, which exhibited nasal gland secretion, voided a major portion of their salt load v i a this route, while the renal mechanism in both salt and f r e s h water ducks accounted for only a sm a l l source of elimination. The efficiencies of the kidney and nasal glands i n removing the i n i t i a l salt load are compared using i s o t o p i c a l l y 22 l a b e l l e d Na C l . 4. A p r e l i m i n a r y report i s made on the ionic composition of excess eye secretion observed accumulating on the feathers below the inner canthus i n N a C l a c c l i m i t i z e d ducks. Implications of the H a r d e r i a n glands as a possible source of this f l u i d are made fr o m gland weight comparisons i n fresh and salt water ducks. REFERENCES ASH, R.N. 1969. Plasma osmolal ity and s a l t gland secretion in the duck. Quart. J . Exp. Phys io l . Log. Med. S c i . 54(1):- 68-69. BARTTER, F.C., G.W. LIDDLE, L.E. DUNCAN, J.K. BARBER, and C. DELEA. 1956. The regulation of aldosterone secretion in man: The role of f l u i d volume. J. C l i n . Invest. 35: 1306 - 1315. BARTTER, F.C., I.H. MILLS, E.G. BIGLIERI, AND C. DELEA. 1959. Studies of the control and physiologic action of aldosterone. Rec. Prog. Horm. Res. 15: 311 - 344. BARTTER, F.C. 1963. Regulation of the volume and composition of ext ra -c e l l u l a r and i n t r a c e l l u l a r f l u i d . Ann. N.Y. Acad. S c i . 110: 682 - 703. BENSON, G.K. and J.G. PHILLIPS. 1964. Observations on the h i s to log i ca l structure of the supraorbital glands from sa l ine- fed and fresh water-fed domestic ducks (Anas platyrhynchos). J . Anat., Lond. 98: 571 - 578. BERSON, S.A. and R.S. YALOW. 1955. Cr i t ique of e x t r ace l l u l a r space measurements with small ions; Na and B r 2 spaces. Science 121: 3 4 - 3 6 . BOND, C.F. and P.W. GILBERT. 1958. Comparative study of blood volume in representative aquatic and non aquatic b i rds. Amer. J . Phys io l . 194(3): 519 - 521. CHI EN, S., D.G. SINCLAIR, C. CHANG, B. PERIC, and R.J. DELLENBACK. 1964. Simultaneous study of c ap i l l a r y permeabil ity to several macromolecules. Amer. J . Phys io l . 207 (3): 513 - 520. DAWSON, A.B., H.M. EVANS, and G.H. WHIPPLE. 1920. Blood volume studies: 111 Behavior of a large series of dyes introduced into the c i r cu l a t i n g blood. Amer. J . Phys io l . 51: 232 - 240. DOUGLAS, D.S. 1970. E lect ro ly te excretion in seawater loaded herring gu l l s . Amer. J . Phys io l . 219 (2): 534 - 539. EGGLETON, M.G. 1951. The state of body water in the cat. J . Phys io l . 115: 482 - 487. FELT, V., V. VRBENSKY and L. MARIKOVA. 1964. Influence of g lucocort icoids on the plasma and ex t r ace l l u l a r volume and the d i s t r i bu t i on of cho les tero l , phospholipids and fa t t y acids in plasma and ex t r a ce l l u l a r f l u i d . Med. Exp. 10: 119 - 127. (40 G I L B E R T , A. B. 1963. E f fect s of estrogen and thyrox in on blood volume of the domest ic cock. J . Endoc r i n . 26: 41-47. G R E G E R S E N , M.I. and R. A. RAWSON. 1959. B lood vo lume. P h y s i o l . Rev. 39: 307. H A J J A R , R. , F. S A T T L E R , B. G. ANDERSON , and G. GWINUP. 1970. Def in i t ion of the st imulus to secret ion of the nasa l salt gland of the sea-gu l l . H o r m . Metab. Res. 2 (1): 35 - 37. HANNON, J . P. and J . L. D U R R E R . 1963. Seasonal var ia t ions in the blood volume and c i r cu la t i ng metabol i te l eve l s of the husky dog. A r t i e A e r o m e d i c a l Lab. , A A L - T D R - 6 2 - 5 3 , M a r c h . H O L M E S , W. N. , D. G. B U T L E R and J . G. P H I L L I P S . 1 9 6 l . Ob se r -vations on the effect of mainta in ing glaucous-winged gulls (Larus g lau-cescens) on f re sh water and sea water for long per iods . J . Endoc r i n . 23: 53 - 61. H O L M E S , W. N. , J . G. P H I L L I P S and D. G. B U T L E R . 1 961. The effect of ad renoco r t i ca l steroids on the rena l and e x t r a - r ena l responses of the domest ic duck (Anas p latyrhynchos). Endocr ino logy 69: 483 - 495. H O L M E S , W.N . 1965. Some aspects of osmoregulat ion i n rept i le s and b i r d s . A r ch i v e s D 'Anatomie M ic ro scop ique et de Morpholog ie E x p e r i -mentale. 54: 491 - 514. HUGGINS, R. A. , E. L. SM ITH, and S. D E A V E R S . 1963. Vo lume d i s -t r ibut ion of Evans blue dye and iodinated a lbumin i n the dog. A m e r . J . P h y s i o l . 205: 351 - 356. HUGHES , M . 1970. C l oaca l and sa l t -g land ion excret ion in the gu l l , L a ru s g laucescens, acc l imated to i nc reas ing concentrations of sea water . Comp. B iochem. P h y s i o l . 32 (2): 315 - 325. K E Y S , A. and J . B R O Z E K . 1953. Body fat i n adult man. P h y s i o l . Rev. 33: 245. KR I STA , L. M . , C.W. C A R L S O N and O. E. OLSON. 1961. Some effects of sal ine waters on ch icks , lay ing hens, poults, and duckl ings. Pou l t r y Sc i . 15: 938 - 944. M A N E R Y , J . F. 1954. Water and e lect ro ly te metabo l i sm. P h y s i o l . Rev. 34: 334 - 417. (41 M E D WAY , W. and M . R. K A R E . 1959. Water metabo l i sm of the growing domest ic fowl with spec ia l reference to water balance. Pou l t r y S c i . 38: 631 - 638. M c F A R L A N D , L. Z. 1964. M i n i m a l salt load requ i red to induce secret ion f r o m the nasa l salt glands of seagul ls. Nature 204: 1202 - 1203. M O O R E , F. D. , L . H . TOB IN and J . C. AUB. 1943. Studies with r ad i o -act ive d i - azo dyes. III. The d i s t r ibut ion of rad ioact ive dyes i n t umo r -bear ing m i c e . J . C l i n . Invest. 22: 161 - 172. M O O R E , F. A. , K. H. O L E S E N , J . D. M c M U R R Y , H . V . P A R K E R , M . R. B A L L , and C M . B O Y D E N . 1963. The body c e l l mass and i ts supporting environment - - body compos i t ion i n health and d isease. W. B. Saunders, Ph i l ade lph ia . P O R T M A N , O. W. , K. P. M c C O N N E L L and R. H. R IGDON. 1952. B lood volumes of ducks using human se rum a lbumin labeled with radiocodine. P r o c . Soc. E x p e r . B i o l , and Med. 81: 599 - 601. P R E N T I C E , T. C. , W. SIRI, N.I. B E R L I N , G. M . H Y D E , R . J . PARSONS , E. E. JO INER, and J . H. L A W R E N C E . 1952. Studies of tota l body water wi th t r i t i u m . J . C l i n . Invest. 31: 412 - 418. PROSSER , C. L. and F. A. BROWN. 196 l . Comparat ive A n i m a l P h y s i -ology. W. B. Saunders Co. , Ph i l ade lph ia . RE ID, J . T. , C. C. B A L C H , and R. F. G L A S C O C K . 1958. The use of t r i t i u m , of ant ipyrene, and of N -acety l - 4 -amino -ant ipy rene in the measurement of body water in l i v i n g rabbits . B r i t . J . Nut. 12: 43 - 51. R O V N E R , A. R. and J . W. CONN. 1963. A s imple and p rec i s e method for the simultaneous measurement i n man of p l a sma vo lume, r a d i o -bromide space, exchangeable potass ium, and exchangeable sodium. J . of Lab . and C l i n . Med. 62 (3): 492 - 500. S C H M I D T - N I E L S E N , K. , C. B. J O R G E N S E N and H. CSAKI . 1958. E x t r a r e n a l salt excret ion i n b i r d s . A m e r . J . P h y s i o l . 193 (1): 101 - 107. S C H M I D T - N I E L S E N , K. I960. The sa l t - sec re t i ng gland of mar i ne b i r d s . C i r cu l a t i on 21: 955 - 966. S C H M I D T - N I E L S E N , K. and Y. T. K I M . 1964. The effect of salt intake on the s ize and function of the salt gland of ducks. The Auk 81: 160 - 172. (42 S C H M I D T - N I E L S E N , K. 1964. Secret ion and E x c r e t i o n . Phys io logy of salt glands, p. 269. S p r i n ge r - Ve r l a g . B e r l i n . S TURKE I , P. D. 1965. C i r c u l a t i o n . A v i an Phys io logy. 2nd edit ion. C o r n e l l Univ. P r e s s , Ithaca. V ISSCHER, M . B. , E. S. F E T C H E R , C. W. C A R R , H. P. G R E G O R , M. S. B U S H E Y and D. E. B A R K E R . 1944. Isotopic t r a ce r studies on the move -ment of water and ions between intes t ina l lumen and blood. A m e r . J . P h y s i o l . 142: 550 - 575. 43 T A B L E I. Comparisons of plasma volume (T-1824 Space), extra-82 3 c e l l u l a r f l u i d volume (Br Space), and total body water (H2O Space) i n f r e s h and N a C l (0. 483 N) water acclimated ducks (Anas platy-rhynchos), gulls (Larus glaucescens), and White Leghorn roosters (Gallus domesticus). Hematocrit values represent means of individual values f r o m 2 - 3 p r e - s a l t load blood samples. The sample number i n each measurement is indicated i n ( ). a = Significant difference (p =<0. 01) b = No significant difference (p = <0. 40) BSRDS Body Wt. (gm.) Hemat. T-1824 Space (ml.) B r 8 2 Space (ml.) H^O Space (ml.) fresh water ducks 3091.2 a ±148.15 (7) 0.434 b ±0.010 (7) 185.4 ±8.2 (11) 765.7 ±38.2 (7) 2120.6 ±108.9 (11) salt water ducks 2352.8 a ±74.0 (7) 0.417 b ±0.012 (7) 158.6 ±5.1 (12) 623.4 ±42.0 (7) 1512.2 ±76.2 (7) gulls ; 835.1 ±13.2 (2) 0.512 ±0.078 (2) 59.9 ±2.4 (2) 321.3 ±31.1 (2) 734.6 ±73.9 (2) roosters 2506.0 ±110.9 (2) 0.479 ±0.002 (2) 106.2 ±1.3 (2) 724.5 ±99.4 (2) 1362.6 ±89.3 (2) 45 T A B L E II. P l a s m a volumes (T-1824 Space) and e x t r a - c e l l u l a r 82 fl u i d volumes (Br Space) c o r r e c t e d for body weight and total body water; total body water (H2O Space) correc t e d for body weight. The standardized compartment values are expressed as either % 3 body weight or % Space. The sample number i n each case are those l i s t e d in Table I. a = Significant difference (p = <0.05) b = No significant difference BIRDS T-1824 SPACE % ;body wt, % H^O space B r 8 2 SPACE % body wt. % H^ O space H|O SPACE % body wt. fresh water ducks 5.75 a ±0.16 9.19b ±0.48 24.88 b ±1.00 36.35 b ±1.58 68.54 b ±0.84 saSt water ducks 6.49a ±0.27 10.59 b ±0.52 26.43 b ±1.38 41.31 b ±2.02 63.97 b ±2.66 guHs 7.16 ±0.17 8.14 ±0.23 38.24 ±3.10 43.64 ±2.95 87.94 ±1.14 roosters 4.43 ±0.32 7.81 ±0.35 28.79 ±2.66 52.92 ±3.81 54.32 ±1.09 47 T A B L E III. Changes i n B r and H2O Spaces following i n t r a -venous injection of 0. 2% body weight (v/w) of 5 N NaCl. Maximum 8 2 post-salt load B r Spaces represent the larg e s t volumes observed during the 60 minute period following salt injection. % change i n 8 2 B r Space represents the magnitude of change relative to the mean p r e - s a l t load volume. Recorded too are the volumes of collected nasal gland secretion where present. Mean pre- and post-salt load 82 B r Spaces are given with their standard e r r o r s . a = Significant difference (p = <0.01) • "' Xoan Max. Max. , Naaal Gland Mean Mean Pre load Poat load Chgnge i n % Change Sec re t i on Preload Poatload 1 l5B°a B r 1 ' ? ? 8 C ° B r , s ^ » c e B r^Space ( m l . ) H|O Space H|O Space FRESH HATES DUCKS C-6?2 C-6#l c-5?6 c-6#j c-3?5 c-6#5 c-3#l X 4SE 628 .44 19.1 S50.9±2}.6 ?06.0 1:21.6 341.5 * 0.4 ?Z2.9±46.5 ?45.7 ±52.1 566.7 ± 2 6 . 1 757.6 IOO5.7 1176.4 787-2 701.8 51.6 162.4 163-5 45.5 55-1 7-50 19-50 18.46 5.82 2.07 IO.59 * ±5 - 4 9 none <0.5 1.26 none none 1960.04.57.1 ' 0 1 7 . 0 * 39.; ?163.7±50.: 2480.5± 12.3 2582.4*55.2 2221.7tfie.s 1 6 1 8 . 8 * 5 1 . ; 2206.6*68.0 2593.4*69.7 2407.3*55.2 2248.6*29.6 1575-1*21-5 SALT WATER DUCKS C-l£4 C-4#5 C- l # l C-2?2 C-?#4 c-iii X 573-7* 17-6 607.5*25 .7 621.8 * 3.8 766.3 ±55.9 776.9 ± 7.6 5 1 5 . 4 * 1 8 . 1 500.1 =k 4 .6 772-5 977.2 931.7 691.9 609.4 150,7 208.9 154.8 176.5 109-5 24.25 27.20 19.92 54.25 21.87 25.49 a * 2.50 20.82 2.45 5.16 5-17 54 .25 >6;5-7*55-5 .631.9*50.5 . 5 1 6 . 1 * 1.4 .576.4*47.5 . 7 7 0 . 6 * 4 7 .6 .193-7*51-5 •395-9* 5.5 1375-9± 52-5 1624.0150.9 l9l5-8±59-9 1275.8*51.1 1^57-3*57-2 GULLS G-1 G-2 X *SE 552.5 ± 6-7 290.2 * 5.4 451.1 400.9 9 6 . 8 110.7 28.04 58.15 55 .09 ± 7 -14 6.14 5-95 75°M ± 7 . 1 713-1*5.9 751.6*17-7 7 1 4 . 9 ± 9.4 ROOSTERS R- l R-2 X ±-Sfi 6 2 5 . 1 * 1 1 . 7 625.6=fc 5.5 725-7 968.4 100.6 144.4 16.10 17.54 -16.82 1 1 . 0 1 - 1275-54.11.4 1277.8*31.1 1451.9*19.8 1483.6*27.1 49 T A B L E IV. Sodium elimination v i a cloacal f l u i d and nasal gland secretion following intravenous injection of 5N N a C l (0. 2% body weight) i n f r e s h and N a C l (0. 483N) water fed ducks (Anas platyrhynchos), Glaucous-winged gulls (Larus glaucescens), and White Leghorn roosters (Gallus domesticus). In those b i r d s 22 which received trace amounts of Na C l (5 - 15 mC) the i s o -topi c a l l y l a b elled salt was administered together with the 5 N N a C l salt load. Means are given together with their standard e r r o r s . a£q. NB injected BLOACAL EXCRETION + * o f Ha* n£q.Na Injected NASAL GLAND SSJHET ION ^ U o f No o & l . I l o injected INJECTED N o 2 2 :pm X 10*^ N a 2 2 in CLOACAL EXCRETION -4 * N a 2 2 cpm x l O injected N a 2 2 in NASAL GLAND SECRET ION „ „ -4 * N o Cpm x 10** Injected F R i S h iATER D'JCKS C - 6 £4 C - 5 #4 C - 3 C - 6 0} c-3#5 C - 6 ^ C - 5 #1 J 1 . 0 0 2 0 . 0 0 50.00 56.05 55.25 2 9 . 0 0 5 0 . CO 1 .26 1.11 0.17 0 . £ 6 0.44 1.65 0 . 9 2 4 . 0 5 5 . 5 4 0 - 5 8 2 .58 1 .25 5 .6Z 5.06 0 . 155 0 . 1 0 4 0 . 0 0 0 0 . 0 0 0 1.065 0 . 0 0 0 0.000 0 . 4 4 0.52 0 . 0 0 0 . 0 0 5 - 67 0 . 0 0 0.00 1.276 1.506 1.465 19-12 8.09 2 0 . 6 6 1 .49 0 . 6 2 1.42 8 0 4.72 NO D R I P O . 5 6 DR IP X * SE }.21 * 0 . 7 5 1.54 ± 0 . 5 8 S/.LT * A T £ R DUCKS C-4 #1 c - 5 #1 C-1 #1 C-2 #4 . ° - 3 #5 C - 2 £2 2 6 . 0 0 26.50 25.00 24.50 26.50 25.00 27.50 0 . 0 0 0 2.172 o.4fia 0.694 0.255 0 .475 0.655 O . 0 0 8.19 2.09 2.85 0 . 6 8 1.69 5-05 4 . 1 6 2 14 . 5 5 8 11.866 1 .446 2.95* 2.98O 18 . 2 6 0 16.06 5 4 . 8 6 51.60 5.96 11.07 11-95 6 6 . 40 1-551 1.571 NO 12.97 F L U I D O .85 1 8 8 . 8 8 217-87 14 . 1 9 15-87 X * S E 5-15 * 0 . 9 7 51-12 ±.9.59 • CULLS G - l C-2 X *SE 8.50 e.oo 0 . 1 1 4 2.049 1.54 25.61 1} .47*12• 5 .095 5-081 5 9 - 9 4 65.51 62.22*1 .8 O .675 O .651 48 .25 1-55 5.50 0 . 1 0 114 .11 1J6 .24 15-13 15.90 ROOSTERS R - l R-2 R-5 JTiSE 22.00 27.00 21.50 5-194 5 - 1 9 8 4 . 6 0 5 25.61 11.85 21.41 18 .96*4.4 --0-479 70.67 1 4 . 7 0 -51 T A B L E V. E l e c t r o l y t e concentrations of simultaneously sampled cloacal f l u i d , nasal gland secretion and plasma at in t e r v a l s p r i o r to and following the injection of 0 . 2 % body weight (v/w) of 5 N N a C l . Ion concentrations are given as mEq/1. Simple Time min. - before • a f t e r B a i t l o a d i n g CJOBCBI F l u i d V o l m e . Concentration (ml.) ; i a * ci" Hosel Clcnd S e c r e t i o n Volume Concentration (ml.) He* CI Ploeraa Concentration Ne* C l " FMSH W A T E R D I C K S C-3 #6 + iao 7 . 1 7 7.53 23.0 131 . 2 15.2 113.3 136.2 153.2 101.3 11+5.1+ c-6 #5 • +H2 +120 2 . 5 1 13.^2 77.1 1 0 7 . 0 57. V 8 0 . 0 173 .1+ 162.9 170.3 11+0.9 s m W A T E R B O C K S C-l # 1 - 100 - 60 + 20 + 1*0 + 60 + 90 + 120 6.65 6.72 6.00 6 8 . 5 39 . 1 8 0 . 2 55A i t i f . 8 65.1* 7 . 2 4 6.13 5 . 0 6 2.1+0 592.0 602.0 600.0 569.6 591+.9 606.5 59>.9 585.1+ 155.1+ 11+6.9 151.7 157.9 155.0 153.6 15?.2 138.1+ 136.3 131+.9 129 .1+ G'JLL G-l - 65 - 25 + 82 + 122 + 130 3A3 1+.59 6 . 6 5 89 . 1 100.5 16>r.5 1*6.2 58.0 160 . 1+ 5 . 9 0 0.25 817.3 390.3 11+1.8 11*0.1+ 1 6 9 . 1 11+7. S 1 5 0 . U 118.0 1 2 6 . 7 li+i*. i+ 120.8 123.3 B O O S T E R R - l + h + 75 + 130 12.1+0 10.97 13.33 7W.1 I63.7 173.7 32.1* 1 6 8 . C 1 2 7 . 2 15V.2 156.8 169.6 -53 T A B L E VI. E l e c t r o l y t e concentrations of eye flui d r elative to plasma and spontaneous nasal gland secretion i n ducks (Anas  platyrhyncho s) r e a r e d on f r e s h w a t e r and N a C l (0. 483N) solution. Concurently produced samples were taken during the 2 - 3 week period p r i o r to the t e r m i n a l experiments. Ion concentrations are given as mEq/1. EYE FLUID Na* K* Cl"" N a + PLASMA K + C l " SPONTANEOUS N A S A L G L A N D SSCRST ION, . N a + . . . K + Cl + SALT WATER DUCKS C -5 #3 C-2 #3 C-2 #5+ C-5+ #6 C-5 7 '6 C-5 ,-45 •••• • c-5 #1 C-J+ #1+ C-1 #1 c-i+ #3 . 276.0 196.5 13^.8 112.0 208.0 176.1+ 136.8 15^.0 15+5.2 136.8 29.2 5+0.0 1+9.2 98.5+ 3h.h 36.0 27.6 72.8 . 27.2 16.8 255.0 178.5+ 161.2 15+5.6 162.8 158.6 151.0 15+6.0 15+3.6 11+5+.2 1V6.5+ 5+.6 J+.l 1+.0 • 3.6-3.7 3.8 2.9 5+.6 3.*+ 5+.2 125.0 119.0 106.5 115+.8 113.0 108.0 105+.0 106^8 192.0 300.0 3^6.0 1+00.0 6.6 11.2 12.0 11.0 16.0 11+0.1+ • FRESH WATER DUCKS C-6 #1 C-6 #2. C-6 #3 C-6 #lf C-6 #5 . 150.8 129.2 106.0 136.8 136.8 28.0 2V.0 26.1+ 5+0.0 33.6 155.8 157.0 15+9.8 155.8 155.0 3.9 1+.6 5+.8 3.7 , 3 A 55 T A B L E VII. Absolute and correc t e d weights of Harderian glands, nasal glands, and kidneys f r o m f r e s h water and N a C l (0. 483N) water reared P e k i n ducks (Anas platyrhynchos). Means are given together with their standard e r r o r s . Sample sizes are indicated by the numbers i n ( ). a = Significant difference (p = <0. 001) b = Significant difference (p = <0.00l) DUCKS Harderian Glands mg. % Dry Wt. Wet.Wt Ddy.Wt. grams Nasal Glands mg. % Dry Wt. Wet Wt.LBdy.Wt. grams Kidneys mg. % Dry Wt. Wet Wt.Bdy. Wt. grams fresh water (11) 0.213 ±0.024 0.982 ±0.087 33.29 a ±2.82 0.019 ±0.005 0.318 ±0.017 10.93 b ±0.55 4.23 ±0,39 19.16 ±1.84 0.644 ±0.054 salt water (24) 0.269 ±tf.0l3 1.190 ±0.056 51.16 a ±2.53 0.252 ±0.011 1.047 ±0.051 44.91 b ±2.24 4.03 ±0.14 18.36 ±0.65 0.798 ±0.045 57 F I G U R E 1. Changes i n f l u i d compartment volumes and plasma N a + concentration i n response.to salt loading i n a fr e s h water fed duck, Anas platyrhynchos, which failed to produce nasal gland secretion. 0. 2% body weight (v/w) of a 5 N N a C l solution was injected intravenously at the time indicated by the v e r t i c a l l i n e . Effects of the salt load were observed i n the following compartments: Graph© E C F volume (Br Space); G r a p h © Total body water (H^O Space); Graph© In t r a c e l l u l a r volume 3 82 (H2O Space - B Space); Graph(4^) P l a s m a N a + concentration (mEq/1). D • gait loaded duck C-3 #1 . -e C o n t r o l f r e s h water duck C-6 #2; no salt load. salt load T I M E <HRS> r 59 F I G U R E 2. Changes i n f l u i d compartment volumes and plasma Na"*" concentration i n response to salt loading i n a f r e s h water fed duck, Anas platyrhynchos, which demonstrated nasal gland secretion. Conditions of the salt load and coordinates of the measured responses are the same as those described i n Figu r e 1. © o Salt loaded duck C -3 #3. © © Control fresh water duck C-6 #2; no salt load. to b' w in b b plasma Na+cone. intracellular vol . f l iO H^ O s p a c e ( l i t ) Br8 space ( l i t ) A 01 o o <n «g co to o o o o ro OJ ^ i - ro b b ro ro U ro ro w ro O O M t» » b b '>-» "M b fit o u a © © ® e 61 F I G U R E 3. Changes i n flu i d compartment volumes and plasma N a + concentration i n response to salt loading i n N a C l fed duck, Anas platyrhynchos, which demonstrated nasal gland activity. Conditions of the salt load and coordinates of the measured responses are the same as those described i n Figur e 1. • p gait loaded duck C-2 #4. © © Con t r o l salt water duck C - 4 #5; no salt load. 63 F I G U R E 4. Changes i n f l u i d compartment volumes and plasma Na concentration i n response to salt loading i n a Glaucous-winged gull (Larus glaucescens) which demonstrated nasal gland activity. Conditions of the salt load and coordinates of the measured responses are the same as those described i n F i g u r e 1. • • Salt loaded gull G-1. TIME (^s.) 65 F I G U R E 5. Changes i n f l u i d compartment volumes and plasma Na"*" concentration i n response to salt loading i n a White Leghorn rooster, Gallus domesticus. Conditions of the salt load and coordinates of the measured responses are the same as those described i n F i g u r e 1. • Q Salt loaded rooster R-2; no nasal gland present. salt load TIME (hrs) 67 F I G U R E 6. N a s a l gland responses as compared to changes i n E C F volume after intravenous salt loading. Maximum post-salt 82 load B r Space increases are plotted against volumes of collected nasal gland secretion. F l u i d was collected u n t i l secretion stopped. © = N a C l solution (0.483N) fed ducks (Anas platyrhynchos); © - f r e s h water fed ducks (Anas platyrhynchos); = gulls (Larus glaucescens). 35.0 ® 30.0 25.0 20.0 15.0 10.0 \ ® 5.0 \ ® ® -©- TO ©-5.0 I © © 10.0 15.0 20'.0 82 ® 25.0 30.0 35.0 40.0 45.0 50.0 axirnum °io Change Br Space after Salt Loading 69 F I G U R E 7. Sodium elimination v i a c l o a c a l and nasal gland routes i n intravenously salt loaded gulls (Larus glaucescens), salt and f r e s h water fed ducks (Anas platyrhynchos), and White Leghorn roosters (Gallus domesticus). The amount of sodium i s expressed as a percentage of the injected load (10 mEq/kg. body wt.). Means are presented with their standard e r r o r s . Sample sizes are indicated by the numbers i n ( ). 80 J IN J BOTH) 60 ho S 8 2 R E T £2 V I A 2 0 N A S A L GLAND S£.= 1.78% X " 51.12/o SE=0.58% \/ / A G U L L S ( 2 ) S A L T WATER DUCKS (7) F R E S H WATER DUCKS (7) ROOSTERS ( 2 ) 3 0 . % I N J E C T E D Na + EXCRETED V I A C L O A C A 20 1 0 X=13.47# S E = 1 2 . 1 3 ^ G U L L S ( 2 ) X=5«J5?S SE=0.97^  . X = 3 . 2 1 # SE-O.75^  X*18.96% S A L T WATER DUCKS (7) F R E S H WATER DUCKS ( 2 ) ROOSTERS (£) 

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