Evaluation of nonstarch polysaccharide-degrading enzymes in broiler diets varying in nutrient and energy levels as measured by broiler performance and processing parameters

Abstract

SUMMARY An experiment was conducted to evaluate the effect of 2 nonstarch polysaccharide-degrading enzymes (NSPase) on broiler performance when supplemented in corn-soybean meal diets varying in nutrient profiles. Three nutrient profiles [control diet (PC), diet with reduced energy and protein levels (NC1), and diet with a reduced energy level (NC2)] and 3 enzyme treatments (control, NSPase A, and NSPase B) were used in a 6-wk broiler trial. The nutrient profile of the control diet met the dietary specifications of a local commercial integrator. The NC1 diet was achieved by equivalent reductions (4%) in total protein and energy (133 kcal/kg) levels from the PC diet, and the NC2 diet was achieved by a 133 kcal/kg (4%) reduction in energy level compared with the PC diet. Broilers were fed the starter diet through 12 d of age, a grower diet through 26 d of age, and a finisher diet through 41 d of age. Body weight was reduced (P < 0.05) at d 12 and 26 in the NC1 diet as compared with the other 2 diets. Body weight of broilers fed the NC2 diet was reduced (P < 0.05) compared with broilers fed the PC diet on d 26. An increase (P < 0.05) in FCR was also observed through the starter period in the NC1 diet. Significant improvements (2 to 4%) were observed in FCR with the inclusion of both NSPase enzymes through the starter and grower periods of the experiment. An interaction between diet and enzyme treatment was observed for d 41 BW, with an increase (P < 0.05) being observed with NSPase B inclusion in the NC2 diet. Additionally, NSPase B inclusion increased (P < 0.05) breast meat weight in broilers fed the PC diet. Therefore, NSPase inclusion can improve growth performance in market broilers and allow for reduced nutrient inclusion rates in an effort to reduce costs.