Effects of dietary herbal powder supplementation on inflammatory cytokines, cecal microbiota, and serum metabolites in finishing Kele pigs

A study was designed to test the efficacy of herbal powder supplement (HPS) on serum inflammatory cytokines, cecal microbial communities, and serum metabolites in finishing Kele pigs. Forty healthy finishing Kele pigs with an initial body weight of 42.67 ± 1.73 kg were randomly assigned to four groups of 10 pigs each. Pigs received a basal diet without HPS (group A) or supplemented with 0.1% (group B), 0.3% (group C), or 0.5% HPS (group D) for 35 days. Among the inflammatory cytokines, group B showed significantly higher serum TGF-β1 and lower IFN-γ levels than the other groups ( P  < 0.05). HPS supplementation did not affect alpha-diversity indices of the cecal microbiota. At the genus level, the relative abundances of Faecalibacterium and Blautia were higher in group B than in group A ( P  < 0.01). The relative abundances of Bacteroides and Lachnospiraceae _ AC2044 _ group were higher in group C than in group A ( P  < 0.05), whereas Treponema was more abundant in group D ( P  < 0.01). Differential metabolites were significantly enriched in the primary bile acid biosynthesis pathway. Glycocholic acid was positively correlated with TGF-β1 and negatively correlated with IFN-γ ( P  < 0.05). These findings indicate that dietary supplementation with 0.1% HPS may improve the inflammatory cytokine profile of TGF-β1 and IFN-γ in finishing Kele pigs. This effect was associated with specific cecal bacteria, including Faecalibacterium , and serum metabolites such as glycocholic acid.