Effect of a Multi‐Carbohydrase on Growth Performance, Metabolizable Energy, Nutrients Digestibility and Intestinal Morphology of Broiler Chickens

The effects of a multi-carbohydrase supplementation (MS, 1250 Xylanase, 750, β-glucanase, 2500 β-mananase and 1500 α-galactosidase U/kg of basal feed) at a level of 0.05% diet on growth performance, metabolizable energy, nutrients utilization and intestinal morphology in broiler chickens were investigated. A total of 160 day-old male Ross 308 (10 birds/pen; n=4) were fed 4 diets (corn or wheat without or with MS) from 0-42 d. Performance was monitored at 21 and 42 d and excreta were collected from d 17 to 20 for neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP) and fat digestibility and ap-parent metabolizable energy corrected for nitrogen (AMEn) measurements. On d 21, jejunal segment were used for histological analysis and its contents were collected for viscosity determination. Birds fed corn diets had better (P<0.01) body weight gain (BWG) and feed conversion ratio (FCR) than birds fed wheat-based diet, while birds fed MS had better BWG and FCR and lower feed intake (FI) than birds fed non-MS diet. Birds fed diets containing MS had lower digesta viscosity (–28%) compared to birds fed diets without MS (P<0.01) and a greater reduction of viscosity due to MS was observed in birds fed wheat diets (–36%) than in corn diets (–13%). Birds receiving diets with MS derived more dietary AMEn (2.15%) compared to those fed diets without MS (P<0.01). Digestibility of NDF and CP was higher (16% and 6.4%, respectively) in birds fed corn-based diet compared to birds fed wheat-based diet and in this context, digestibility of NDF in birds fed MS was higher (10%) than birds fed non-MS diet (P<0.05). Moreover, birds fed MS-diets had higher villus height (5.4%) and villus height: crypt depth ratio (6.5%) compared to birds fed non-MS diet (P<0.01). These results indicated that, although diet type impacted growth performance but MS was efficacious across diet types, implying that degradation of dietary fibrous components by feed enzymes may stimulate performance in broilers.