One experiment was conducted to evaluate the effect of microbial enzymes, phytase, on the performance of the birds and on the digestibility coefficient of dry mater (DM), crude protein (CP), phosphorus (P) and calcium (Ca) and the values of apparent ileal digestible of energy (AIDe) and nitrogen corrected apparent metabolizable energy (AMEn). A total of 384 Avian Farm male broiler chicks, 10 days old, during 14 d-trial were used in a factorial arrangement of 2 x 3, with eight replicates, eight chicks per unit were used. The diets were formulated to contain two levels of Ca and available P normal (0.93%Ca/0.45%Pd) and low (0.80%Ca/0.33%Pd) x three level of phytase (o - control, 500 FTU phytase - 1 and 750 phytase 2). Chromic oxide (0,5%) was added to the diets, as an indigestible marker, to estimate ileal digestibility. Phytase 1 improve weight gain in 3.4% and phytase 2 in 2.8%. Both enzymes improved feed:gain ratio in 3% and the digestibility of CP, E, P and Ca. Phytase addition, also, improved AIDe, however the enzyme did not improve the EMAn.
enzyme; phytase; corn-soyben meal; broilers chicks; nutrient digestibility
