Utilization of phytate phosphorus and calcium as influenced by microbial phytase, cholecalciferol, and the calcium: total phosphorus ratio in broiler diets

Abstract The present study was performed to evaluate the potential of microbial phytase and cholecalciferol (D3) for improving the utilization of phytate P and Ca and the influence of the Car:total (t) P ratio in a corn-soybean meal diet fed to broilers from hatch to 21 d of age. A 4 x 4 x 2 factorial arrangement of treatments was used: 1.1, 1.4, 1.7, and 2.0:1 Ca:tP ratio; 0, 300, 600, and 900 U of phytase/kg of diet; and 66 and 660 micrograms of D3/kg of diet. Another four treatments were included: the four Ca:tP ratios with 6,600 micrograms of D3 addition, but without phytase. Added phytase linearly increased (P