Evaluation of dietary replacement of soybean meal by canola meal supplemented by β-mannanase (Hemicell) on performance of broiler chicks.

To investigate the replacement value of canola meal (CM) for soybean meal (SBM) in broiler diets supplemented with Hemicell (containing -mannanase activity) on performance of growing broiler chicks, three hundred sixty unsexed 1-d-old chicks were randomly allocated to 4 treatments, each of which had 9 pens of 10 chicks per pen. Four iso-energetic and isonitrogenous diets were fed ad libitum as starter (days 0-21), grower (days 22-42) and finisher (days 43-49). All diets included a high proportion of corn as the main cereal component. The diets with CM included (15, 15 and 5%) CM in place of SBM in starter, grower and finisher diets, respectively. Experimental groups were: control group (Corn-SBM), corn-SBM with Hemicell, corn-SBM-CM without Hemicell, and corn-SBM-CM with Hemicell. The inclusion of CM in place of SBM reduced feed intake (FI) and body weight gain (BWG) of birds and increased feed conversion ratio (FCR) compared with birds fed on control diet. The addition of Hemicell to CM-included diets improved FI, BWG and FCR; however, only improvement in BWG and body weight (BW) compared with CM-included diets with no enzyme was statistically significant. Enzyme inclusion in SBM-based-diets-improved-BW,-BWG-and-FCR-(P 0.05).