Abstract
BACKGROUND: Intestinal microbial homeostasis and metabolic balance play a crucial role in maintaining normal physiological function in horses. Exogenous stress involving abrupt turns and jumps during show jumping significantly impacts intestinal microbial homeostasis and metabolic balance in these animals. RESULTS: By comparing rectal (faecal) samples from 10 Warmblood horses collected before and immediately after a show jumping competition on the same day, we observed substantial alterations in intestinal microbial homeostasis and metabolic balance post-exercise. Microbial evenness significantly increased following the competition, accompanied by enrichment of specific taxa such as Bacteroides, Ruminococcus, Prevotella, and Fibrobacter. Metabolite analysis revealed a marked decrease in antioxidant-related compounds, including orsellinic acid, 2,3-dimethyl-2-cyclohexen-1-one, and (1 R,6 R)-1,4,5,5a,6,9-hexahydrophenazine-1,6-dicarboxylate. Conversely, glucosan and thiamine pyrophosphate levels increased. Post-competition, membrane lipid metabolism pathways were significantly downregulated, while antioxidant responses and energy metabolism pathways were upregulated. Spearman correlation analysis indicated positive associations between Fibrobacter, Ruminococcus, and Prevotella with energy metabolism-related metabolites, whereas Lysinibacillus correlated positively with metabolites involved in antioxidant activity and intestinal mucosal protection. CONCLUSION: Collectively, our findings demonstrate that show jumping induces shifts in intestinal microbial homeostasis and metabolic balance in Warmblood horses. These adaptations appear conducive to preserving epithelial integrity and enhancing energy provision to meet the demands of high-intensity exercise. This study provides novel insights into the impact of acute high-intensity exercise on equine gut microbial dynamics and metabolism, offering a theoretical basis for probiotic-based interventions to support intestinal health in sport horses.