Dietary supplementation with Bacillus subtilis DSM 32315 alters the intestinal microbiota and metabolites in weaned piglets.

Abstract

The study was conducted to investigate the effects of dietary Bacillus subtilis (BS) DSM 32315 on the intestinal microbiota composition and metabolites of weaned pigs. Sixty-four piglets were allocated to two groups (control and BS), each group including eight replicates with four piglets. Dietary BS DSM 32315 increased (P<0·05) the abundances of jejunal Leucobacter and Cupriavidus, ileal Thermus, Coprococcus and Bifidobacterium, as well as colonic Succiniclasticum; and increased the concentrations of ileal straight-chain fatty acids, colonic propionate, branched-chain fatty acids (BCFAs), and tyramine, but decreased (P<.05) the colonic indole concentration. The ileal and colonic microbial community structure tended to cluster into two groups. LEfSe analysis identified five microbial biomarkers in jejunum and eight biomarkers in ileum in the BS group, and three biomarkers in colon in the control group. The ileal Bifidobacterium abundance was positively correlated (P<0·05) with isovalerate concentration, while the colonic Actinobacteria and Lactobacillus abundances were negatively correlated (P<0·05) with indole concentration. These findings suggest that dietary supplementation with BS DSM 32315 could alter the diversity, composition, and metabolites of intestinal microbiota in weaned piglets. Weaned piglets are often accompanied with impaired gastrointestinal tract and intestinal disorder affecting their growth. This study demonstrated that dietary BS DSM 32315 presented a beneficial role in gut health via regulating intestinal microbiota composition and metabolites.