Dietary supplementation with Bacillus-based probiotic improves gut health in the weaned piglets challenged by rotavirus.

[BACKGROUND] As probiotics, Bacillus strains may regulate some physiological functions in animals. This study aimed to evaluate whether dietary supplementation with a Bacillus-based probiotic could alleviate gut damage induced by rotavirus (RV) infection in piglets. Twenty-four piglets were randomly assigned into 2 groups fed with the basal diet (n = 16) and the diet containing 10 colony-forming unit Bacillus spores/kg (n = 8). On d 8, 8 piglets fed with the diet supplemented with Bacillus-based probiotic and 8 piglets fed with basal diet were orally infused with RV, while the residue piglets had oral gavage of sterile essential medium. The trial duration was 12 d.

[RESULTS] RV challenge induced diarrhea, significantly destroyed the morphology of jejunal mucosa (P < 0.05), significantly increased RV-antibody and RV non-structural protein 4 of jejunal mucosa (P < 0.05), significantly impaired antioxidant capacity (including malondialdehyde level, total antioxidant capacity and catalase activity), immunity (such as interleukin 2, interleukin 4 and secreted immunoglobulin A levels), mucins and the mRNA expression of tight-junction-related (such as Zonula occludens 1, occludin) and apoptotic-related (including B-cell lymphoma/leukaemia-2-associated X protein, B cell lymphoma/leukaemia-2, cysteinyl aspartate specific proteinases) genes of jejunal mucosa (P < 0.05), and, to some extents, affected the bacteria community structure and abundance of ileal digesta in piglets. However, Bacillus-based probiotic administration could significantly attenuate the negative effects of RV infection on gut health of piglets (P < 0.05).

[CONCLUSIONS] These findings suggested that supplementing Bacillus-based probiotic in the diet could decrease diarrhea rate, and improve gut health in weaned piglets, which was associated with regulating intestinal antioxidant capacity, apoptosis, and microbiota.