Pediococcus acidilactici Long21 alleviates intestinal sensitivity and improves gut health in dogs via regulating intestinal metabolic profiles

The aim of this study is to explore the differences in intestinal microbial communities between healthy dogs and intestinal sensitivity dogs, to isolate and characterize a potential probiotic strain, and investigate its role in improving intestinal health and alleviating intestinal sensitivity in dogs.Results: The result showed that dogs with intestinal sensitivity had significantly higher fecal scores, pathogenic bacteria counts and fecal moisture, but lower nutrients digestibility (P <0.05).

Fecal microbiota transplantation from healthy dogs effectively improved these indicators and enhanced serum antioxidant and anti-inflammatory capacities (P <0.05). 16S rRNA sequencing analysis showed that healthy dogs had higher intestinal microbial α and β diversity, with Pediococcus acidilactici enriched and Shigella increased in healthy and diarrheic dogs, respectively (P <0.05). Pediococcus acidilactici Long21 intervention improved fecal traits, reduced pathogenic bacteria abundance, increased nutrients digestibility, and normalized antioxidant function and inflammatory indicators of dogs with intestinal sensitivity (P <0.05).

Metabolomics revealed 2085 differential metabolites, enriched in amino acid and energy metabolism, with glutamate, malate and pyruvate as hub metabolites correlated with nutrients digestibility and fecal traits.Conclusion: Intestinal flora imbalance is correlated with intestinal sensitivity-induced diarrhea in dogs. P. acidilactici Long21 supplementation alleviated intestinal sensitivity-associated diarrhea and improves intestinal health by regulating microbiota, correcting metabolic disorders and enhancing nutrients utilization, providing a theoretical basis and candidate strain for microecological intervention.