The effect of phosphorus, phytase enzyme, and calcium on the performance of layers fed wheat-based diets

Abstract

A trial was performed to test the effects of two levels of Ca (3.7 and 4.0%), two levels of available P (0.2 and 0.4% until 55 wk, 0.11 and 0.22% from 55 to 67 wk), and three levels of phytase enzyme (0, 250 and 500 FTU kg −1 ) on the performance of laying hens fed diets based on wheat and soybean meal. Phytase supplementation had only small effects, likely because the endogenous phytase in the wheat liberated sufficient phytate-bound P to compensate for only marginally deficient levels. In contrast to what has been found with corn-based rations, there were no negative effects of high levels of AP or of enzyme, suggesting that the effect of exogenous phytase was more complex than a simple liberation of phytate P. Endogenous phytase should be considered when formulating rations based on wheat. Key words: Phytase, layers, wheat, phosphorus, calcium