Nutritive values of wheat bran-based broiler diet supplemented with different classes of enzymes

Abstract

Previous studies have shown that inclusion of exogenous enzymes in broiler diets can improve metabolizable energy intakes, digestibility and performance parameters. However, there is limited information on the comparative effect of different enzymes in wheat bran-based broiler diet. This study investigated the effect of different enzyme classes on metabolizable energy (ME) values of wheat bran as well as the performance parameters and nutrient retention of broilers. A total of 216 mixed-sex one-day-old chicks were fed either the basal diet or test diet (20% basal diet replaced with wheat bran) without or with supplementation of carbohydrase-cocktail (CC), multi-enzyme (MEnz) and single-carbohydrase (SC). The enzymes increased (P<0.001) the ME values of wheat bran but SC had the highest increase for apparent ME, nitrogen-corrected apparent ME and true ME values of wheat bran. Neither performance parameters of feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR) nor economic benefit (EB) was affected by the interaction between diets and enzymes. A significant dietary effect (P<0.05) was observed as higher FI, lower FCR, and better EB on the test diet compared to basal diet. The enzyme inclusions, however, had similar improvements on (P<0.05) on BWG, FCR and EB of broilers. The dietary enzymes increased fat and phosphorus (P) retentions on both test and basal diets (P<0.001), with birds fed CC added to test diet showing the highest phosphorus retention. In conclusion, enzyme inclusions in wheat-bran based diet improved the ME values of wheat bran and the nutrient retention of broilers, although broiler performance was unaffected. The inclusion of CC in 20% wheat bran-based diet can be economically useful in improving P retention of broilers, with potential benefit for reducing P losses to the environment.