Next-generation non-starch polysaccharide-degrading, multi-carbohydrase complex rich in xylanase and arabinofuranosidase to enhance broiler feed digestibility
This study was carried out to evaluate the effect of a multi-carbohydrase complex (MCC) rich in xylanase (Xyl) and arabinofuranosidase (Abf) on overall broiler feed digestibility in broilers. Energy utilization and digestibility of dry matter (DM), organic matter (OM), protein, starch, fat, and insoluble and soluble fibers were measured using the mass-balance method. The experiment was carried out on 120 broilers (3-week-old chickens). Broilers were distributed over 8 treatments to evaluate the effect of the dietary arabinoxylan content and nutrient density with and without MCC (Rovabio® Advance). The graded content of arabinoxylan (AX) was obtained using different raw materials (wheat, rye, barley, and dried distillers' wheat). Diet-energy density was modified with added fat. Measurements indicated that nutrient density and AX content had a significant effect on most digestibility parameters. Apparent metabolizable energy (AME) was significantly increased (265 kcal kg-1) by MCC. The addition of MCC also resulted in significant improvement in the digestibility of all evaluated nutrients, with average improvements of 3.0, 3.3, 3.2, 3.0, 6.2, 2.9, 5.8, and 3.8% units for DM, OM, protein, starch, fat, insoluble and soluble fibers, and energy utilization, respectively. The interaction between MCC and diet composition was significant for the digestibility of OM, fat, protein, and energy. Nutrient digestibility and diet AME were negatively correlated with AX content (P < 0.001). However, the addition of MCC resulted in a reduction of this negative effect (P < 0.001). The AME of diets with and without the addition of MCC were successfully predicted by the diet digestible nutrient (i.e., starch, protein, fat, insoluble and soluble fibers) content with and without MCC (R2 = 0.87; RSD = 78 kcal kg-1). This study confirms that the presence of AX in wheat-based diets and wheat-based diets with other cereals and cereal by-products reduces nutrient digestibility in broiler chickens. Furthermore, the dietary addition of MCC, which is rich in Xyn and Abf, reduced deleterious effect of fiber and improved overall nutrient digestibility in broiler diets.