DIETAS DE FRANGO COM 10% DE FARELO DE ARROZ, COM FITASE E BAIXA SUPLEMENTAÇÃO DE MICROMINERAIS: DESEMPENHO AOS 21 DIAS

The experiment was conducted to determine the effect of increasing levels of phytase on broilers performance at twenty - one days of age in diets with 10% rice bran and 60% reduction in the inorganic iron, copper, zinc and manganese. Three hundred birds of mixed-sex Cobb lineage were used in six treatments with five replicates and ten birds per experimental plot in DIC. The isonutritivas rations were formulated to meet the nutritional requirements, except for the microminerals under study. A commercial phytase enzyme with a declared activity of 10,000 Phytase Units (FTU) per gram. The experimental treatments were: T1: basal diet; T2: Diet with 10% of rice bran, with 60% reduction in the supplementation of minerals Mn, Zn, Fe and Cu and without phytase; T3: T2 + 400 FTU per kg; T4: T2 + 800 FTU per kg; T5: T2 + 1,200 FTU per kg; T6: T2 + 1,600 FTU per kg. The use of 10% of rice bran with 60% reduction in supplementation of microminerals in broiler diets from 7 to 21 days did not affect (P> 0.05) the performance variables independently studied at the level of phytase used.