Comparison of Gut Microbiota and Metabolic Characteristics Between Miechongshu-Treated and Untreated Yili Horses.

Overview

• This study compared the gut microbiota composition and metabolic characteristics of Yili horses treated with the anthelmintic Miechongshu to untreated horses.
• The research aimed to understand how anthelmintic treatment influences intestinal microbial communities and metabolism in horses.

Study Design and Methods

• Twelve Yili horses were randomly divided into two groups:
  • Control group (C) – no anthelmintic treatment.
  • Treated group (T) – received Miechongshu orally at 0.36 g/kg body weight on day 0.
• Fecal samples were collected from the horses on day 14 post-treatment.
• Gut microbial composition was analyzed using 16S rRNA gene sequencing, a technique to identify and quantify bacterial populations.
• Metabolic profiling of fecal samples was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to detect metabolites and assess metabolic changes.

Key Findings: Gut Microbiota Composition

• Alpha diversity, a measure of species richness and diversity within a sample, showed no significant difference between treated and control groups (p > 0.05), indicating that overall microbial richness was not strongly altered by treatment.
• At the bacterial phylum level:
  • The relative abundance of Halobacterota was significantly increased in the Miechongshu-treated horses (p < 0.05).
• At the family level:
  • Prevotellaceae abundance increased significantly in treated horses.
  • Christensenellaceae abundance decreased significantly in the treated group.
• At the genus level, the relative abundance of an unspecified genus was significantly decreased (p < 0.05), though the genus name was not provided in the abstract.

Key Findings: Metabolic Characteristics

• A total of 98 metabolites differed significantly between groups:
  • 64 metabolites were upregulated in treated horses compared to controls.
  • 34 metabolites were downregulated.
• KEGG pathway analysis identified four metabolic pathways with significant differences:
  • Tryptophan metabolism
  • Purine metabolism
  • Fatty acid biosynthesis
  • Carotenoid biosynthesis
• Specific metabolite changes:
  • Tetradecanoic acid (a fatty acid) and adenosine (a nucleoside involved in purine metabolism) were significantly decreased in treated horses.
  • Tryptophol, a metabolite related to tryptophan metabolism, was significantly increased.

Implications and Conclusions

• The anthelmintic treatment induced notable shifts in the composition of the gut microbiota, particularly increasing certain bacterial families and phyla linked to intestinal physiology.
• Metabolic changes suggest the treatment impacts important biochemical pathways related to amino acid metabolism, nucleotide metabolism, fatty acid production, and antioxidant compound biosynthesis.
• The findings highlight that while anthelmintics are used to control parasitic infection, they also influence the intestinal microecological balance and host metabolic homeostasis.
• This study provides important insights for evaluating the broader consequences of anthelmintic use and underscores the need for balanced intestinal health management in horses.