Dietary <i>Bacillus subtilis</i> PB6 Enhances Reproductive Performance by Modulating Gut Microbiota, Barrier Function, and Inflammation in <i>Clostridium perfringens Type A</i>-Infected Sows.

Abstract

<i>Bacillus subtilis</i> is aerobic or facultatively anaerobic. After entering the gastrointestinal tract, its spores germinate and colonize the gut, inhibiting the growth of harmful aerobic bacteria (<i>Escherichia coli</i>, <i>Streptococcus</i>, <i>Staphylococcus aureus</i>). However, it remains unclear whether <i>B. subtilis</i> can inhibit <i>Clostridium perfringens type A</i> infection. In this study, <i>B. subtilis</i> PB6 was added to the diets of pregnant sows infected with <i>Clostridium perfringens type A</i>, which significantly improved the reproductive performance and reduced the incidence of bloat in sows and diarrhea in neonatal piglets. The treatment significantly increased the abundance of intestinal probiotics (<i>B. subtilis</i>, <i>Lactobacillus</i>, <i>Limosilactobacillus reuteri</i>, <i>Lactobacillus johnsonii</i>, <i>Muribaculaceae</i>, <i>Lactobacillus amylovorus</i>, and <i>Lactobacillus reuteri</i>) in sows and decreased the relative abundance of <i>Clostridium perfringens type A</i> after feeding <i>B. subtilis</i> administration. These probiotics can repair the intestinal tissue and improve intestinal histomorphology, and enhance the expression of MUC2 and sIgA in sows, thereby further strengthening the mucosal immune function. <i>B. subtilis</i> can also reduce the levels of inflammatory factors (CRP, IL-1β, and IFN-γ) and attenuate the inflammatory response in sows and neonatal piglets. Taken together, our results suggest that dietary supplementation with <i>B. subtilis</i> PB6 could reduce bloat in sows and diarrhea in piglets while improving intestinal barrier function and microbial balance in sows.