The objective of experiments were evaluate to effect of phytase in broilers rations, during growing (22 to 35 days) and final (36 to 45 days of age) phases. Two experimental rations were used each phase, whereas the first diet recommended by the the broiler integration (C-1) and the second suggested by furnished company enzyme (C-2). Treatments consisted in T1 and T4 - rations without enzyme and T2 and T3 - rations with enzyme. A complete randomized design was used in a 2 x 2 factorial model (two rations x two levels of enzyme) with nine replicates and thirty birds per unit. The enzyme was used in 100 g/ton of ration. Statistically significant difference (P<0.01) was found among the treatments to weight gain and feed:gain ratio to growing phase, not happened identical with final phase (P>0.05). The birds yield parts evaluation was statistically different (P<0.01) in legs yield with experimental rations suggested by E-2, without phytase. The rations formulated with the E-1 that showed better results in relation to rations E-2.
carcass valuation; poultry; performance; enzymes
