ORIGINAL RESEARCH article

Front. Vet. Sci.

Sec. Animal Reproduction - Theriogenology

Volume 12 - 2025 | doi: 10.3389/fvets.2025.1588432

This article is part of the Research TopicRecent developments in Animal Reproduction: combining research with practiceView all 14 articles

Endometrial Microbiome in Mares with and without Clinical Endometritis

Provisionally accepted
  • Oklahoma State University, Stillwater, United States

The final, formatted version of the article will be published soon.

Chronic endometritis (CE) is a major contributor to reproductive failure in mares and in many other mammals. Current diagnostic methods lack sensitivity due to the lack of pathognomonic clinical signs or ultrasound findings. Although microbial involvement was suggested no definitive causative agents have been isolated and the few studies conducted are compromised by the dependence on culturable aerobic organisms. This study compares the endometrial microbiomes of 13 healthy and 13 CE-diagnosed mares that were carefully matched to their locations and management. Microbial diversity was significantly reduced in CE mares, indicating dysbiosis. Burkholderia and Chamydia were dominant in both groups but significantly more abundant in CE samples. Linear discriminant analysis revealed Burkholderia, Hyphomicrobium, and Erwiniaceae as significantly enriched in CE. Functional pathway analysis showed increased metabolism-related pathways in CE-associated microbiota, while healthy mares exhibited greater microbial richness and functional diversity. These findings underscore microbial imbalance as a potential driver of CE and highlight the utility of sequencing-based microbiome profiling for improved diagnosis and therapeutic targeting in equine reproductive health. This preliminary work contributes to establishing a uterine microbiome reference for mares, with implications for fertility management.

Keywords: Chronic endometritis, mare, Equine, microbiome, Uterus

Received: 06 Mar 2025; Accepted: 08 Jul 2025.

Copyright: © 2025 Guo, Holyoak and DeSilva. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Udaya DeSilva, Oklahoma State University, Stillwater, United States

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