Supplementation of phytase on diet improves the apparent ileal digestibility of amino acids and P in growing piglets

The present study evaluated the effect of dietary phytase supplementation on the performance, apparent ileal digestibility (AID) of amino acids (AA) and P of growing piglets. A total of 32 growing piglets with a mean body weight (18.36 +/- 1.39 kg) were divided into 4 groups randomly: positive control group (A) is basal diet without phytase: negative control group (B) is similar to A except that available P was reduced by 0.18%, and two experiment groups C and D with 500 and 1000 U/kg phytase (5000 U/g), respectively, in B group diet. All piglets were fed for 30 days and then killed for sample collection. Consequently, no significant difference was observed on average daily gain (ADG) and ratio of feed to gain (FIG) in all groups, but ADG was 3.5% higher in D group compared with positive control group. Supplementing of phytase increased the AID of methionine, threonine, isoleucine, histidine and lysine (P<0.05). For D group, the AID of P was increased 24% (P<0.001) and the amount of P excreted was decreased by 17.9% (P<0.05) compared with A group. Dietary supplementation of phytase improved P digestion and utilization in growing piglets under the condition of the present study.