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Scientific reports2022; 12(1); 14790; doi: 10.1038/s41598-022-18971-6

The healthy equine uterus harbors a distinct core microbiome plus a rich and diverse microbiome that varies with geographical location.

Abstract: The goal of this study was to understand the composition and existence of the resident uterine microbiome in healthy mares and to establish the presence of a core microbiome for the healthy equine uterus. We analyzed the microbiomes of 35 healthy mares that are long-time residents of three farms in Oklahoma, Louisiana, and Australia as well as that of 19 mares purchased from scattered owners in the Southern Mid-Western states of the United States. Over 6 million paired-end reads of the V4 region of the 16S rRNA gene were obtained resulting in 19,542 unique Amplicon Sequence Variants (ASVs). ASVs were assigned to 17 known phyla and 213 known genera. Most abundant genera across all animals were Pseudomonas (27%) followed by Lonsdalea (8%), Lactobacillus (7.5%), Escherichia/Shigella (4.5%), and Prevotella (3%). Oklahoma and Louisiana samples were dominated by Pseudomonas (75%). Lonsdalea (28%) was the most abundant genus in the Australian samples but was not found in any other region. Microbial diversity, richness, and evenness of the equine uterine microbiome is largely dependent on the geographical location of the animal. However, we observed a core uterine microbiome consisting of Lactobacillus, Escherichia/Shigella, Streptococcus, Blautia, Staphylococcus, Klebsiella, Acinetobacter, and Peptoanaerobacter.
Publication Date: 2022-08-30 PubMed ID: 36042332PubMed Central: PMC9427864DOI: 10.1038/s41598-022-18971-6Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

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.

The study investigates the microbiome within the uterus of healthy horses, revealing its diverse makeup and dependence on geographical location while also identifying a core set of microbes commonly present.

Research Objective

  • The primary goal of this study was to comprehend and describe the combination of microbes, also known as the microbiome, residing in healthy equine uteri. Researchers aimed to identify a core uterine microbiome, i.e., a set of microorganisms that is habitually present in every healthy equine uterus, regardless of location or other conditions.

Methodology

  • Under this study, the uterine microbiomes of 35 healthy mares were analyzed. The mares were residents of three different farms located in Oklahoma, Louisiana, and Australia.
  • Additionally, the microbiomes of 19 mares purchased from various owners in the Southern Mid-Western states of the U.S. were also analyzed.
  • The team collected and investigated over 6 million paired-end reads of the V4 region of the 16S rRNA gene, providing a substantial sample to work with.
  • This analysis led to the identification of 19,542 unique Amplicon Sequence Variants (ASVs), a measure of microbial diversity within the samples. These ASVs confirmed the presence of 17 known phyla and 213 known genera of microorganisms.

Findings

  • The most common genus was Pseudomonas, found in 27% of all animals tested. Following Pseudomonas, in decreasing order of prevalence, were Lonsdalea (8%), Lactobacillus (7.5%), Escherichia/Shigella (4.5%), and Prevotella (3%).
  • Geography held an essential bearing on the uterine microbiome- Pseudomonas dominated (75%) the samples from Oklahoma and Louisiana. Interestingly, Lonsdalea was the most often seen genus in Australian samples (28%) but was absent from samples from the other locations.
  • Notwithstanding the geographical usage, the study identified a core uterine microbiome consisting of Lactobacillus, Escherichia/Shigella, Streptococcus, Blautia, Staphylococcus, Klebsiella, Acinetobacter, and Peptoanaerobacter. These microorganisms were present across the samples analyzed.

Implications

  • The findings of this research highlight the vast diversity, richness, and evenness of the equine uterine microbiome and how it’s heavily reliant on the animal’s geographical location.
  • Knowledge of a core uterine microbiome could potentially guide promoting uterine health and treating diseases related to uterine microbial imbalance.

Cite This Article

APA
Holyoak GR, Premathilake HU, Lyman CC, Sones JL, Gunn A, Wieneke X, DeSilva U. (2022). The healthy equine uterus harbors a distinct core microbiome plus a rich and diverse microbiome that varies with geographical location. Sci Rep, 12(1), 14790. https://doi.org/10.1038/s41598-022-18971-6

Publication

ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 12
Issue: 1
Pages: 14790

Researcher Affiliations

Holyoak, G R
  • Department of Veterinary Clinical Sciences, Oklahoma State University, Stillwater, OK, USA.
Premathilake, H U
  • Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, USA.
Lyman, C C
  • College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
Sones, J L
  • School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA.
Gunn, A
  • School of Agricultural, Environmental and Veterinary Sciences and Gulbali Institute, Charles Sturt University, Wagga Wagga, NSW, Australia.
Wieneke, X
  • Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, USA.
  • Department of Pathology and Laboratory Medicine; Center for Genomics, Anne and Robert H. Lurie Children's Hospital, Northwestern Feinberg School of Medicine, Chicago, IL, USA.
DeSilva, U
  • Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, USA. udaya.desilva@okstate.edu.

MeSH Terms

  • Animals
  • Australia
  • Clostridiales / genetics
  • Escherichia / genetics
  • Female
  • Horses / genetics
  • Lactobacillus / genetics
  • Microbiota / genetics
  • Prevotella / genetics
  • RNA, Ribosomal, 16S / genetics
  • Uterus

Conflict of Interest Statement

The authors declare no competing interests.

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