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Veterinary sciences2023; 10(4); doi: 10.3390/vetsci10040259

Relationship between Clinical Uterine Findings, Therapy, and Fertility in the Mare.

Abstract: Persistent breeding-induced endometritis (PBIE) is a major cause of subfertility in horses and the susceptibility is increased by several factors. The aim of this study was to determine the effects of clinical uterine findings and PBIE therapies, respectively, on pregnancy rate in mares. The analysis included records from 220 mares (390 cycles) inseminated at an artificial insemination (AI) center in Switzerland. Gynecological examinations were performed repeatedly before and after AI to determine cervical tone, uterine edema, and intrauterine fluid accumulation. Pregnancy rate was lower (p < 0.001) in barren mares compared to mares of other reproductive status. A more flaccid cervix (p = 0.009) was observed at the time of ovulation in pregnant cycles, but there was no difference (p > 0.05) regarding uterine edema. Intrauterine fluid accumulation reduced pregnancy rate (p = 0.002). Oxytocin administration had beneficial effects on pregnancy rate (p = 0.015), especially for barren mares, while uterine lavage did not have any effect (p > 0.05). The results show that cervical tone and intrauterine fluid accumulation, but not its degree, are useful parameters for assessment of fertility in mares. Oxytocin treatment improved pregnancy rates in mares with PBIE while uterine lavage had a limited effect.
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Publication Date: 2023-03-29 PubMed ID: 37104414PubMed Central: PMC10142731DOI: 10.3390/vetsci10040259Google 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 research is about the relationship between clinical uterine findings in mares, the treatments for persistent breeding-induced endometritis (PBIE), and how these affect pregnancy rates. The findings revealed that cervical tone and fluid accumulation in the uterus have an impact on mare fertility, with mares having a more flaccid cervix and no intrauterine fluid accumulation more likely to get pregnant. Oxytocin treatment was found beneficial, improving pregnancy rates especially for barren mares.

Objective and Methodology of the Study

  • The objective was to determine how clinical findings in horse uteruses, and the therapies for PBIE, influence the rate of pregnancy in mares.
  • The study involved analyzing records from 220 mares, accounting for 390 cycles, that were inseminated at an Artificial Insemination (AI) center in Switzerland. Cervical tone, uterine edema, and accumulation of intrauterine fluid were examined consistently before and after the AI process.

Key Findings

  • Barren mares were less likely to get pregnant compared to mares in other reproductive states.
  • In the cycles where pregnancy occurred, it was noticed that the mares had a more flaccid cervix at the time of ovulation. However, the presence or absence of uterine edema did not make a significant difference in the pregnancy rates.
  • Intrauterine fluid accumulation was seen to decrease the rate of pregnancies.
  • Oxytocin administration was found to be beneficial for pregnancy, particularly beneficial for barren mares. Meanwhile, uterine lavage or the cleansing of the uterus did not show a significant effect on the pregnancy rates.

Conclusion

  • The study concludes that two significant factors for assessing fertility in mares are the cervical tone and the accumulation of fluid inside the uterus.
  • The administration of Oxytocin was seen to increase the rates of pregnancies in mares with PBIE, while the process of uterine lavage (cleaning the uterine wall) showed a limited effect on improving pregnancy rates.

Cite This Article

APA
Scarlet D, Malama E, Fischer S, Knutti B, Bollwein H. (2023). Relationship between Clinical Uterine Findings, Therapy, and Fertility in the Mare. Vet Sci, 10(4). https://doi.org/10.3390/vetsci10040259

Publication

Veterinary sciences
ISSN: 2306-7381
NlmUniqueID: 101680127
Country: Switzerland
Language: English
Volume: 10
Issue: 4

Researcher Affiliations

Scarlet, Dragos
  • Clinic of Reproductive Medicine, Vetsuisse Faculty Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
  • Institute of Veterinary Anatomy, Vetsuisse Faculty Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Malama, Eleni
  • Clinic of Reproductive Medicine, Vetsuisse Faculty Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Fischer, Sophie
  • Clinic of Reproductive Medicine, Vetsuisse Faculty Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Knutti, Barbara
  • Tierarztpraxis KLC, 1562 Corcelles-près-Payerne, Switzerland.
Bollwein, Heinrich
  • Clinic of Reproductive Medicine, Vetsuisse Faculty Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.

Conflict of Interest Statement

The authors declare no conflict of interest.

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Citations

This article has been cited 5 times.
  1. Fehin B, Scott CJ, Arango-Sabogal JC, de Mestre AM, Mouncey R. Associations between endometrial swab bacteriology and cytology findings and live foal rates in Thoroughbred broodmares in the United Kingdom. Equine Vet J 2026 Mar;58(2):348-358.
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  2. Mahmood K, Hassan M, Channa AA, Ghafoor A, Riaz A. Comparative analysis of breeding patterns and reproductive efficiency of mares in subtropical conditions of Pakistan. Vet Med Sci 2024 Sep;10(5):e1582.
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  3. Gil-Miranda A, Caddey B, Orellana-Guerrero D, Smith H, Samper JC, Gomez DE. Vaginal and Uterine Microbiota of Healthy Maiden Mares during Estrus. Vet Sci 2024 Jul 18;11(7).
    doi: 10.3390/vetsci11070323pubmed: 39058007google scholar: lookup
  4. Prete CD, Nocera FP, Piegari G, Palumbo V, Martino L, Cocchia N, Paciello O, Montano C, Pasolini MP. Use of cytobrush for bacteriological and cytological diagnosis of endometritis in mares. Vet World 2024 Feb;17(2):398-406.
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  5. Mahmood K, Ali Channa A, Ghafoor A, Riaz A. Factors affecting the efficiency of equine embryo transfer (EET) in polo mares under subtropical conditions of Pakistan. PLoS One 2024;19(2):e0298066.
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