Use of different combinations of enzyme complexes in broiler diets

Abstract

Two experiments were carried out to investigate the effect of “on top” addition of different enzyme complexes, the enzyme alfa-galactosidase and three sources of the enzyme phytase available on the market, in broiler diets. In the first experiment, 1260 one-day-old Cobb 500R chicks were distributed into seven treatments in a completely randomized design (CRD) with six replicates and 30 birds/replicate. Treatments consisted of combinations of different enzyme complexes, namely, complex A (phytase, protease, xylanase, beta-glucanase, cellulase, amylase, pectinase), complex B (protease and cellulase) and complex C (xylanase, amylase and protease); isolated alfa-galactosidase (GAL); and three sources of phytase (P1, P2 and P3) in the diet. The treatments were formulated as follows: T1 - basal diet (BD); T2 - BD + enzyme complex A + enzyme complex B (BDAB); T3 - BDAB + GAL; T4 - BD + complex A + GAL; T5 - BD + complex C + P1 + GAL (BDCG); T6 - BDCG + P2; and T7 - BDCG + P3. The following variables were measured in the experimental period of 42 days: feed intake (FI), weight gain (WG), average final weight (AFW), feed conversion (FC), and carcass yield. Significant differences occurred for AFW, WG and FC in the pre-starter phase. In the second experiment, 112 Cobb 500R chicks aged 25 days were distributed into seven treatments in a CRD with four replicates and four birds/replicate. Treatments were the same as in the first experiment. Nutrient digestibility was evaluated in an experimental period of seven days. Differences were found in the metabolism coefficient of ether extract (MCEE). Dietary inclusion of enzyme complexes improves the AFW and WG of chickens from 1 to 7 days of age and MCEE in the grower phase.