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Home / Equine Research Bank / J Vet Intern Med / Characterization and comparison of fecal microbiota in horse...
Journal of veterinary internal medicine2025; 39(1); e17288; doi: 10.1111/jvim.17288

Characterization and comparison of fecal microbiota in horses with pituitary pars intermedia dysfunction and age-matched controls.

Abstract: Altered gut microbiota has been associated with dopaminergic degenerative diseases in people, but studies on horses with pituitary pars intermedia dysfunction (PPID) are lacking. Objective: Investigate the effect of PPID on fecal microbiota in horses. Methods: Nine horses with PPID and 13 age-matched control horses. Methods: Prospective control study. Fecal samples were collected bimonthly. Microbial analysis used 16S rRNA sequencing to determine the relative abundance at genus and phylum levels, assess alpha and beta diversity and identify core microbiota. Results: Horses with PPID had decreased relative abundances of Christensenellaceae R-7 group (median; 95% confidence interval [CI]: PPID, 2.04; 1.82-2.35 vs control, 2.54; 2.37-2.76; P = .02) and NK4A214 group (PPID, 2.21; 2.02-2.56 vs control, 2.62; 2.44-2.85; P = .05), and significant lower abundances of Romboutsia (log2FoldChange = -3.54; P = .04) and Peptococcaceae uncultured (log2FoldChange = -0.89; P = .04) by differential abundance analysis. However, the abundance of Fibrobacter (log2FoldChange = 0.74; P = .04) was significantly higher in the PPID group. A significant effect of PPID on beta diversity was observed (P = .004), whereas alpha diversity varied with months (P = .001). Seven unique genera were identified in horses with PPID and 12 in control horses. Conclusions: The fecal microbial composition is altered in horses with PPID. These findings support the potential role of the microbiota-gut-brain axis in the pathogenesis of PPID.
© 2025 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.
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Publication Date: 2025-01-24 PubMed ID: 39853825PubMed Central: PMC11758151DOI: 10.1111/jvim.17288Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study investigates the impacts of pituitary pars intermedia dysfunction (PPID), a type of hormone disorder, on the composition of gut bacteria in horses, using sequencing technologies to identify different bacterial populations.

Objective and Methodology

  • The primary aim of this study was to explore how PPID affects the fecal microbiota in horses. To do so, researchers examined fecal samples from nine horses diagnosed with PPID, comparing them with samples from 13 healthy control horses of the same age.
  • The study was designed as a prospective control study, where the fecal samples were collected at regular two-month intervals.
  • The research team used 16S rRNA sequencing, a common method for studying bacterial populations. This approach allowed them to determine the relative abundance of different bacteria at the genus and phylum levels, examine alpha and beta diversity, and identify key components of the microbiota.

Key Findings

  • The research findings indicated significant differences in the makeup of the fecal microbiota between horses with PPID and the control group.
  • Certain bacteria groups – such as the Christensenellaceae R-7 group and NK4A214 group – showed decreased abundance in horses with PPID, while the abundance of a genus called Fibrobacter was significantly higher in the PPID group.
  • Results also showed a significant effect of PPID on beta diversity (a measure of variation in community composition), and the alpha diversity (a measure of species diversity in a community) was observed to vary with months.
  • The team identified seven unique bacterial genera in horses with PPID and 12 unique genera in the control horses.

Conclusion

  • This research demonstrated that PPID alters the composition of the fecal microbiota in horses. Such findings reinforce the idea of a potential role for the microbiota-gut-brain axis in the development of PPID.
  • The precise relationships between hormonal disorders like PPID, gut microbiota, and neurological health remain to be further explored in future studies.

Cite This Article

APA
Wang W, Gibson J, Horsman S, Mikkelsen D, Bertin FR. (2025). Characterization and comparison of fecal microbiota in horses with pituitary pars intermedia dysfunction and age-matched controls. J Vet Intern Med, 39(1), e17288. https://doi.org/10.1111/jvim.17288

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 39
Issue: 1
Pages: e17288
PII: e17288

Researcher Affiliations

Wang, Wenqing
  • School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Gibson, Justine
  • School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Horsman, Sara
  • School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Mikkelsen, Deirdre
  • School of Agriculture and Food Sciences, The University of Queensland, St Lucia, Queensland, Australia.
Bertin, François-René
  • School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
  • College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA.

MeSH Terms

  • Animals
  • Horses
  • Feces / microbiology
  • Horse Diseases / microbiology
  • Pituitary Gland, Intermediate / microbiology
  • Pituitary Diseases / veterinary
  • Pituitary Diseases / microbiology
  • Case-Control Studies
  • Male
  • Female
  • RNA, Ribosomal, 16S / genetics
  • Gastrointestinal Microbiome
  • Prospective Studies

Grant Funding

  • Australian Companion Animal Health Foundation

Conflict of Interest Statement

Authors declare no conflict of interest.

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