Effects of enzyme supplementation on the replacement value of canola meal for soybean meal in broiler diets

Abstract

A broiler growth study was conducted to investigate the replacement value of canola meal (CM) for soybean meal (SBM) in broiler diets with or without the addition of two commercial enzyme products. A total of 3600 broilers were used in this experiment. Four isoenergetic diets replicated 10 times with 90 birds each were fed ad libitum as starter (Day 0–21) and finisher (Day 21–37) crumbles. All diets included a high proportion of sorghum as the main cereal component, and soybean meal (20% and 24.5%) or canola meal (35% and 28.9%) were included as the sole protein concentrate. At Day 38 selected birds from each dietary treatment were commercially processed and carcass yield and weight of selected meat portions were measured. The inclusion of CM in place of SBM and the addition of enzyme to CM-based diets did not affect feed intake, growth, and feed conversion ratio (FCR). Mortality in birds fed the unsupplemented CM diet was significantly reduced compared with the mortality in birds fed the SBM control diet or the CM diets supplemented with enzymes. Birds fed the unsupplemented CM had significantly (P < 0.05) reduced eviscerated weight, breast meat, and thigh yield and a significantly (P < 0.05) reduced water-holding capacity of muscle tissue compared with the SBM control diet. The addition of Enzyme A to CM-based diets increased breast meat and the addition of Enzyme B significantly (P < 0.05) increased dress yield, breast meat, and Marylands (thigh and drumstick portions). Carcass yield and quality on this diet was comparable to the SBM diet.