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Journal of equine science2012; 23(3); 35-40; doi: 10.1294/jes.23.35

Equine Endometrial Gland Density and Endometrial Thickness Vary among Sampling Sites in Thoroughbred Mares.

Abstract: The secretions of the equine endometrial glands are essential for the survival, growth, and development of the conceptus in early pregnancy, and endometrial gland density is directly related to successful pregnancy outcome. Endometrial biopsy is routinely used to assess the reproductive potential of broodmares. Some previous studies have shown that equine endometrial glands are uniformly distributed throughout the uterus; however, other work has shown variation of the endometrial architecture between biopsy sites, suggesting that a single biopsy is not representative of the entire endometrium. The aims of this study were to assess and compare the endometrial gland density and thickness at four sampling sites in the uterus (the central segment of each uterine horn, the uterine horn-body junction, and the caudal portion of the uterine body). Endometrial samples from five nulliparous Thoroughbred mares in diestrus were obtained at necropsy and used for subsequent histomorphometric analysis. The caudal uterine body had a significantly lower endometrial gland density and endometrial thickness than the other sites. This may result in nutrient deprivation and reduced survival of embryos or fetuses in this region of the uterus. The endometrial gland density and endometrial thickness did not significantly differ between the other regions sampled, indicating that they are similarly suitable for embryonic implantation and fetal development. Our results suggest that the endometrial structure of the caudal uterine body of the mare is not representative of the endometrial morphology at other sites. Thus, the caudal uterine body is not a suitable site for routine endometrial biopsy.
Publication Date: 2012-10-18 PubMed ID: 24833993PubMed Central: PMC4013978DOI: 10.1294/jes.23.35Google Scholar: Lookup
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  • Journal Article

Summary

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The research investigates the variations in equine endometrial gland density and thickness in different parts of a mare’s uterus. It suggests that the endometrium in the caudal part of the uterus may not be suitable for biopsy due to its lower gland density and thickness, potentially impacting embryo survival.

Research Aims and Procedures

  • The study aimed to compare the endometrial gland density and thickness in four different parts of the uterus in a horse: the central part of each uterine horn, the uterine horn-body junction, and the caudal part of the uterine body. These measurements can help understand which regions of the uterus are better suited for embryo implantation and fecundity.
  • To carry out this study, endometrial samples were collected from five nulliparous Thoroughbred mares in diestrus at post-mortem for a detailed histomorphometric analysis.

Research Findings

  • The researchers observed that the caudal uterine body had significantly less endometrial gland density and thickness compared to the other parts of the uterus. This could potentially lead to nutrient deprivation and negatively affect the survival of embryos or fetuses in this part of the uterus.
  • There were no significant differences in endometrial gland density and thickness between the other sampled regions. This indicates that these parts are equally appropriate for embryonic implantation and fetal development.

Implications and Conclusions

  • The study’s findings suggest that the endometrial structure of the caudal uterine body of the mare may not be representative of the endometrial morphology in other parts of the uterus.
  • As such, the research discourages the use of the caudal uterine body as a regular site for endometrial biopsy, due to the lower gland density and thickness in this part, which might affect accurate assessment of the mare’s overall reproductive potential.

Cite This Article

APA
Hanada M, Maeda Y, Oikawa MA. (2012). Equine Endometrial Gland Density and Endometrial Thickness Vary among Sampling Sites in Thoroughbred Mares. J Equine Sci, 23(3), 35-40. https://doi.org/10.1294/jes.23.35

Publication

ISSN: 1340-3516
NlmUniqueID: 9503751
Country: Japan
Language: English
Volume: 23
Issue: 3
Pages: 35-40

Researcher Affiliations

Hanada, Michiko
  • Faculty of Animal Health Technology, Department of Animal Health Technology, Yamazaki Gakuen University, 2-3-10 Shoto, Shibuya-ku, 150-0046, Japan ; Laboratory of Large Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
Maeda, Yousuke
  • Laboratory of Large Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
Oikawa, Masa-Aki
  • Laboratory of Large Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.

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Citations

This article has been cited 1 times.
  1. Zhao X, Gao B, Yang X, Zhang A, Jamail G, Li Y, Xu D. The density of endometrial glandular openings: a novel variable to predict the live birth rate in patients with intrauterine adhesions following hysteroscopic adhesiolysis.. Hum Reprod 2021 Mar 18;36(4):965-975.
    doi: 10.1093/humrep/deaa377pubmed: 33486509google scholar: lookup