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behaviour
nutrition
riding science
2021
Cohort Study

Effects of Pasture Grass, Silage, and Hay Diet on Equine Fecal Microbiota.

Authors: Zhu Yiping, Wang Xuefan, Deng Liang, Chen Shulei, Zhu Chunyan, Li Jing

Journal: Animals : an open access journal from MDPI

Summary

# Editorial Summary Understanding how different forage types shape the equine hindgut microbiota is crucial for practitioners advising on nutrition and digestive health, yet comparative data on pasture, silage, and hay have been lacking until now. Researchers assigned 36 horses to each of three diet groups for eight weeks, feeding exclusively pasture grass, silage, or hay before analysing fecal bacterial communities using high-throughput sequencing. Key findings revealed significant microbial shifts: the Lachnospiraceae family—important fibre-fermenting bacteria—was substantially more abundant in hay-fed horses and least abundant in those on silage, whilst Streptococcaceae species (recognised as a core equine intestinal component) were notably depleted in pasture-fed horses compared to hay or silage groups. These distinct microbial signatures suggest that forage type markedly influences hindgut fermentation patterns and bacterial composition, with implications for practitioners selecting feeds to support specific microbiota profiles, manage digestive disorders, or transition horses between dietary regimens. The findings particularly highlight silage's surprising effects on fibrolytic bacteria, warranting careful consideration when incorporating this forage into equine diets and suggesting scope for further investigation into long-term health outcomes associated with these microbial changes.

Read the full abstract on PubMed

Practical Takeaways

  • Forage type significantly influences intestinal microbial populations; switching between pasture, silage, and hay will alter fecal microbiota composition with potential implications for digestive health and performance
  • Pasture grass feeding results in lower Streptococcaceae levels compared to conserved forages, which may warrant consideration when designing nutrition programs for horses with compromised digestive health
  • Understanding these microbiota differences can inform decisions about forage selection and dietary transitions to optimize intestinal health and potentially reduce digestive disturbances

Key Findings

  • Lachnospiraceae family was significantly more abundant in hay-fed horses compared to silage-fed horses
  • Streptococcaceae spp. were present in significantly lower quantities in pasture grass-fed horses versus hay or silage-fed horses
  • Diet type (pasture grass, silage, or hay) produces measurable differences in equine fecal microbiota composition after 8 weeks of exclusive feeding

Conditions Studied

intestinal microbiota compositiondigestive health

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