Nutritional levels of calcium and available phosphorus for white-egg pullets and brown-egg pullets from 0 to 6 weeks of age

Four experiments were accomplished using 720 white-egg pullets and 720 brown-egg pullets from 0 to 6 age weeks, were allotted to a completely randomized design with five calcium levels (.70, .80, .90, 1.00, and 1.10%) or five levels of available phosphorus (.30, .35, .40, .45, and .50%), with four replicates and 18 pullets for experimental unit. The experimental diets were formulated with soybean meal and corn to contain 2900 kcal of metabolizable energy/kg of diet, 18% crude protein, .70% calcium for calcium experiments and .30% of available phosphorus for phosphorus experiments. Diets and water were ad libitum fed during the experimental period. The evaluated characteristics were weight gain, feed intake, feed: gain ratio, bone resistance, bone ash and bone calcium (calcium experiments) or bone phosphorus (experiments of available phosphorus). Requirements of .937% and .961% of calcium and .420% and .423% of available phosphorus for white-egg pullets and brown-egg pullets, respectively, were estimated.