Nutrient digestibility, digesta volatile fatty acids, and intestinal bacterial profile in growing pigs fed a distillers dried grains with solubles containing diet supplemented with a multi-enzyme cocktail

This study investigated the effects of adding a multi-enzyme cocktail (MC) to a distillers dried grains with solubles (DDGS)-containing diet on energy and nutrient coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility, digesta volatile fatty acids (VFA) concentration, and gut bacterial profile using ileal-cannulated barrows (n = 9; 62.7 ± 6.4 Kg initial body weight). Three isocaloric/isonitrogenous diets based on corn and soybean meal with 0 (control) or 30% DDGS (DDGS diet) and DDGS diet supplemented with MC (DDGS + MC) were used. The 3 diets were fed to pigs in a 2-period change over design to obtain 6 observations per diet. A casein-cornstarch-based diet was used in a separate period to determine basal endogenous N and AA losses to estimate standardized ileal digestibility (SID) of AA. All diets contained titanium dioxide as a digestibility marker. Ileal digesta and feces were used for VFA and bacterial profile determination, respectively. The CAID for DM, N, starch, and energy were greater (P < 0.05) in pigs fed the control diet than in pigs fed the DDGS diet. Addition of MC to the DDGS diet improved (P < 0.05) the CAID for DM, starch, and energy, but not N (P > 0.10). The DDGS diet also decreased (P < 0.05) the CAID and SID for AA and the MC improved (P < 0.05) the CAID and SID of some of the AA. Further, the DDGS diet decreased (P < 0.05) the CATTD for DM, N, and energy and tended to decrease (P < 0.10) the CATTD for NDF, whereas the MC improved (P < 0.05) the CATTD for DM and energy, but not (P > 0.10) for N and NDF. However, diet had no effect (P > 0.10) on hindgut nutrient disappearance. Diet did not influence (P > 0.10) digesta pH and VFA concentrations except for isovalerate concentration, which was greatest (P < 0.05) in the DDGS + MC-fed pigs. Bacteroides-Prevotella-Porphyromonas and Enterobacteriaceae abundance were greatest (P < 0.05) in the feces of the DDGS + MC-fed pigs. Additionally, the abundance of the β-xylosidase gene, xynB, from the Bacteroidetes group increased (P < 0.05) when the MC was added to the DDGS diet. However, the DDGS-fed pigs had the greatest abundance (P < 0.05) of Firmicutes. The abundance of Lactobacillus spp. was not affected (P > 0.10) by diet. In conclusion, adding MC to the DDGS diet improved the digestibility of DM, starch, most AA, but not NDF and N digestibility. The results show that addition of MC to the DDGS diet stimulated the growth of intestinal bacteria with xylanolytic and cellulolytic activities.