HYDROLYSIS OF PHYTATE PHOSPHORUS BY CHICKS AND LAYING HENS

The chromic oxide balance method was used to determine the amount of natural phytate phosphorus hydrolyzed by chicks and laying hens. Broiler chicks 4 and 9 wk old and Single Comb White Leghorn hens were fed diets containing corn as the only grain source or diets in which wheat replaced one half of the corn. Feces were collected twice daily during the 7 day test period. The phytate phosphorus recovered in the feces of the 4 and 9 wk old chicks and the laying hens fed the diet containing corn was 100, 98 and 92%. When wheat replaced one half of the corn the recovery was 92, 87 and 87%. The phytase activity in wheat was minimal in vivo; in vitro tests indicated enzyme activity.