UBC Theses and Dissertations
Biological availability of minerals from organic and inorganic sources for the chick Aw-yong, Lai Mon
Availability of six minerals (Ca, P, Mg, Mn, Zn, and Cu) in commercial wheat, triticale, corn and barley samples was estimated with three-week old growing chicks. Effects of soybean meal and wheat fed at different dietary concentration on availability of these minerals were studied. The availability of minerals from specific inorganic sources were also evaluated. Availability value was determined by a balance procedure corrected for endogenous minerals. Results indicated that the availability of calcium, phosphorus, magnesium, manganese, zinc, and copper was 71.0, 67.4, 53.5, 48.4, 49.6 and 78.5%, respectively for the wheat and triticale samples. Copper availability was the highest in corn (87.2%), followed by calcium (70.0%), phosphorus (60.9%), manganese (60.0%), zinc (57.5%) and magnesium (51.0%). The availability of Ca, P, Mg, Mn, Zn and Cu in barley was 68.9, 68.8, 54.9, 54.9, 49.1 and 77.5%, respectively. Significant variation (P ≤ 0.05) exists among the cereal grains tested. Results indicate that mineral availability is influenced by the origin of the samples obtained. Availability of minerals is affected by the concentration of ingredients in the test diet. Significant differences (P ≤ 0.05) were observed in availability for all the minerals tested when soybean meal and wheat were supplied in the test mixture at five levels. Calcium and phosphorus from calcium phosphate were highly available to growing chicks. However, the availability decreased rapidly when the mineral level was in excess of the dietary requirement. Six levels of magnesium (150, 300, 450, 600, 750, and 900 ppm) from magnesium carbonate were evaluated. Results showed that magnesium was highly available to growing chicks. The values ranged from 82.3 to 61.9%. Excess amounts of magnesium in the diet tended to reduce the availability value. Various levels (25, 50, 75, 100 and 125 ppm) of manganese from manganese sulfate were tested. Manganese appeared to be poorly available for the levels tested. Zinc availability from zinc oxide was highly available for the chick. The availability values/ranged from 84.4 to 93% for all the diets containing 25 to 125 ppm of zinc. The availability of copper from copper sulfate was moderate to high (72.1-80.2%) for the low dietary copper concentrations (2-32 ppm). However, the copper availability values (61.8-63.6%) tended to decrease at higher dietary concentration (50-250 ppm).
Item Citations and Data