The effects of distillers dried grains with solubles on apparent nutrient digestibility and passage kinetics of Boer×Spanish castrated male goats

Abstract

This study was conducted to evaluate the effects of different inclusion rates of distillers dried grains with solubles (DDGS) on apparent nutrient digestibility, and passage kinetics in meat goats. Four uniform mature Boer×Spanish castrated goats (51.4±0.9 kg BW) were used in a 4×4 Latin square experimental design. Animals had free-choice access to twice daily 36.5% bermudagrass hay (BGH) and 63.5% concentrates containing 0, 12.7, 25.4 and 38.1% of DDGS (dry matter[DM]basis; w/w proportion) replacing corn and soybean meal in the diet. Concentrates were isonitrogenous with 16% crude protein (CP). Each period consisted of 16 days for diets adjustment followed by 5 days of total fecal and urine collection for the digestion and passage kinetics. Concentrate and hay offered and refused, fecal and urine outputs were monitored daily. The ytterbium-marked BGH was used to determine the passage kinetics. Results indicated that with the inclusion of DDGS increased ether extract (EE) concentrations of total diets from 2.91 (0% DDGS) to 4.33% (38.1% DDGS). No differences were observed in DM and neutral detergent fibre (NDF) digestibility (P>0.05) among treatments. However, DDGS supplementation had a quadratic effect on apparent digestibilities of acid detergent fibre (ADF) and EE (P=0.04). Passage kinetics and nitrogen utilisation were unaffected by DDGS inclusion (P>0.05). Results of this experiment indicated that DDGS can replace up to 38.1% of diet DM for Boer×Spanish castrated goats with no adverse effects on nutrient digestion and passage kinetics.