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BMC veterinary research2025; 21(1); 411; doi: 10.1186/s12917-025-04853-2

Faecal microbiota and serum metabolome association with equine metabolic syndrome in connemara ponies.

Abstract: Faecal microbiome and serum metabolome have been studied in human medicine to provide a better understanding of metabolic derangements including diabetes; however, equivalent studies in equine medicine are limited. This was a case-control study conducted to identify differences in faecal microbiota composition and concurrent serum metabolite patterns between metabolically normal Connemara ponies and those with Equine Metabolic Syndrome (EMS). Thirty privately owned Connemara ponies (15 EMS and 15 controls) were included in the study. EMS was diagnosed by oral sugar test (OST). Blood samples were collected before and after an oral sugar challenge. One concurrent faecal sample was collected from each pony. Sequencing of the V3-V4 region of 16S rRNA gene was used to identify the microbial communities in faecal samples and assess the differences in microbial profiles between groups. Serum metabolites were analyzed using liquid chromatography-high-resolution mass spectrometry (LC-MS). Finally, multi-omics analysis was conducted by integration of microbiota-metabolome datasets to determine potential associations between metabolites and microbiota in EMS. Results: The faecal microbiota community composition was significantly different between EMS and control groups (p = 0.04 and r = 4.3%). EMS ponies showed reduced species richness and evenness compared to normal ponies, however it did not reach significant difference. The EMS ponies showed an enrichment of serum metabolites belonging to triglycerides (TGs), along with a reduction of other metabolite classes. Integrative multi-omics analysis revealed two modules in the metabolome and microbiota datasets that were significantly different between the EMS and control groups (p < 0.05). Conclusions: This study suggests that concurrent faecal microbiota and serum metabolome features significantly differ between Connemara ponies with and without EMS. These results provide insights that may assist in the search for diagnostic markers associated with microbiota changes and novel preventative management methods to manipulate microbiota in horses with EMS.
Publication Date: 2025-07-01 PubMed ID: 40598279PubMed Central: PMC12220031DOI: 10.1186/s12917-025-04853-2Google Scholar: Lookup
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  • Journal Article

Summary

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This research study focuses on examining the differences in faecal microbiota and serum metabolome between normal Connemara ponies and those diagnosed with Equine Metabolic Syndrome (EMS), broadening the understanding of metabolic disorders in the equine medical field.

Objective and Methodology

  • The objective of this study was to identify and analyse existing differences in faecal microbiota and concurrent serum metabolite patterns between EMS diagnosed Connemara ponies and their metabolically normal counterparts.
  • The researchers carried out a case-control study that included thirty privately owned Connemara ponies—15 were diagnosed with EMS, and 15 served as controls.
  • The identification process of EMS was through an oral sugar test (OST).
  • Blood samples were gathered before and after triggering an oral sugar challenge.
  • Each pony provided one concurrent faecal sample.
  • The researchers used sequencing of the V3-V4 region of the 16S rRNA gene to recognize and assess contrasting microbial community profiles among the groups.
  • Liquid chromatography-high-resolution mass spectrometry (LC-HRMS) was utilised for the analysis of the serum metabolites.
  • Finally, an integrative multi-omics analysis of microbiota-metabolome datasets was performed to identify potential associations between metabolites and microbiota in EMS.

Results

  • The study revealed a significant difference in the composition of the faecal microbiota community between the EMS and control groups.
  • EMS ponies displayed reduced species richness and evenness compared to normal ponies, but this difference wasn’t statistically significant.
  • In the serum metabolites, an enrichment was observed in the EMS ponies related to triglycerides (TGs), along with a reduction of other metabolite classes.
  • The multi-omics analysis identified two modules in the metabolome and microbiota datasets that were significantly distinct between the EMS and control groups.

Conclusion

  • The study concludes that there are significant differences in the faecal microbiota and serum metabolome features between Connemara ponies with and without EMS.
  • This research provides valuable insights that might assist in finding diagnostic markers related to microbiota changes and developing new preventative management methods to control microbiota in horses with EMS.

Cite This Article

APA
Al-Ansari AS, Duggan V, Mulcahy G, Yin X, Brennan L, Cotter PD, Patel SH, O'Donovan CM, Crispie F, Walshe N. (2025). Faecal microbiota and serum metabolome association with equine metabolic syndrome in connemara ponies. BMC Vet Res, 21(1), 411. https://doi.org/10.1186/s12917-025-04853-2

Publication

ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 21
Issue: 1
Pages: 411
PII: 411

Researcher Affiliations

Al-Ansari, Ahmed Saleh
  • College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-Khodh, Muscat, Oman. asansari@squ.edu.om.
  • School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland. asansari@squ.edu.om.
Duggan, Vivienne
  • School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
Mulcahy, Grace
  • School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
  • Conway Institute of Biomedical and Biomolecular Research, Dublin, Ireland.
Yin, Xiaofei
  • Conway Institute of Biomedical and Biomolecular Research, Dublin, Ireland.
Brennan, Lorraine
  • Conway Institute of Biomedical and Biomolecular Research, Dublin, Ireland.
Cotter, Paul D
  • SeqBiome Ltd, Cork, Ireland.
  • Teagasc Food Research Centre, Moorepark, Cork, Ireland.
Patel, Shriram H
  • SeqBiome Ltd, Cork, Ireland.
O'Donovan, Ciara M
  • SeqBiome Ltd, Cork, Ireland.
Crispie, Fiona
  • Teagasc Food Research Centre, Moorepark, Cork, Ireland.
Walshe, Nicola
  • School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
  • Department of Biological Sciences, University of Limerick, Castletroy, Co. Limerick, Ireland.

MeSH Terms

  • Horses
  • Animals
  • Feces / microbiology
  • Horse Diseases / microbiology
  • Horse Diseases / blood
  • Horse Diseases / metabolism
  • Metabolome
  • Metabolic Syndrome / veterinary
  • Metabolic Syndrome / microbiology
  • Metabolic Syndrome / blood
  • Metabolic Syndrome / metabolism
  • Case-Control Studies
  • Male
  • Female
  • RNA, Ribosomal, 16S / genetics
  • Microbiota
  • Gastrointestinal Microbiome

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: The study was approved by the UCD Animal Research Ethics Committee (reference AREC-21–02- Duggan) and performed under license from the Health Products Regulatory Authority (HPRA) (reference AE18982/P198). Every pony’s owner’s consent was obtained, and a consent form was signed. Consent for Publication: Not applicable. Competing interests: The authors declare no competing interests.

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