Effects of dietary xylanase plus β-glucanase levels on total-tract nutrient and energy digestibility and N balance of growing pigs fed diets containing corn distiller dried grains

Abstract Corn distiller dried grains (corn-DDG) addition to pig diets has been limited due to fiber concerns. The purposes were to determine the metabolizable energy of corn-DDG (Exp. I) and the dose–response effects of dietary xylanase plus β-glucanase on nutrient and energy digestibility of growing pigs fed diets containing 25% corn-DDG (Exp. II). Pigs in individual cages were submitted to feeding periods of 5 d for voluntary feed intake quantification followed by 5 d for collection of feces and urine. In Exp. I, 10 barrows with 61.10 ± 3.25 kg BW distributed in a randomized complete block design experiment with five replications were fed a reference diet or a test diet (75% reference diet plus 25% corn-DDG). In Exp. II, 10 castrated male pigs with 29.69 ± 3.57 kg BW distributed in a Latin square design (two squares with four replicates in time) experiment were fed with 5 dietary xylanase plus β-glucanase levels (0, 50, 100, 200 or 400 mg/kg) added to diets formulated with 25% corn-DDG. The corn-DDG had 26.5% crude protein, 5.94% ether extract, 55.5% neutral detergent fiber (NDF) and 4,248 kcal/kg gross energy. The metabolizable energy of corn-DDG was 3,657 ± 189 kcal/kg. Increasing dietary xylanase plus β-glucanase quadratically influenced (P < 0.05) the NDF digestibility and digestible energy in growing pigs fed diets containing 25% corn-DDGS. Compared to the control, dietary xylanase plus β-glucanase addition increased digestibility and reduced metabolizability of crude protein. Dietary xylanase plus β-glucanase addition in growing pig diets containing corn-DDG increased NDF digestibility, allowing additional dietary energy and protein availability.