Effect of seminal plasma on uterine inflammation, contractility and pregnancy rates in mares.
Abstract: There is conflicting evidence over the role seminal plasma plays in sperm transport and inflammation within the uterus of mares. In in vitro studies, seminal plasma has been shown to reduce polymorphonuclear neutrophil (PMN) function, but the opposite effect on uterine inflammation has been reported in vivo. Objective: To study the effect of seminal plasma on uterine contractility, inflammation and pregnancy rates by inseminating mares with low doses of sperm free from seminal plasma (Group 1) and containing seminal plasma (Group 2). Methods: Synchronised mares were inseminated with 50 x 10(6) sperm in either skim milk extender or seminal plasma. Uterine lavage was performed 6 h after insemination to assess the inflammatory response. The contraction frequency of the uterus was measured over a 4 min period 10 mins and 6 h after insemination, using B-mode ultrasonography. Pregnancy rates were assessed 16 days after insemination. Results: Uterine contractions were less frequent in Group 1 mares inseminated with seminal plasma and significantly more PMNs were found in the lavage fluid of those mares. Pregnancy rates were identical in both groups (62%). Conclusions: This study provides evidence that seminal plasma decreases uterine contractility and increases the inflammatory response of the uterus to semen. No effect of seminal plasma on pregnancy rates was demonstrated. Conclusions: Mares that develop persistent mating-induced endometritis may have inherently poor uterine contractility and impaired uterine clearance. The presence of seminal plasma during breeding may not be desirable in these mares. The role of seminal plasma in problem mares warrants additional study.
Publication Date: 2005-11-22 PubMed ID: 16295928DOI: 10.2746/042516405775314844Google Scholar: Lookup
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- Journal Article
Summary
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The research investigates how seminal plasma – the fluid that carries sperm – impacts inflammation, muscle contractions in the uterus, and pregnancy rates in mares. Although it was found to decrease uterus contractility and increase inflammation, seminal plasma didn’t show a noticeable effect on pregnancy rates.
Research Objective and Methodology
- The primary objective of this study was to understand the impact of seminal plasma on the uterus’ inflammation, contractility, and pregnancy rates in mares.
- The researchers conducted this by inseminating synchronized mares with a low dose of sperm either without seminal plasma (Group 1) or with seminal plasma (Group 2).
- Later, uterine lavage was performed 6 hours post insemination to evaluate the inflammatory response.
- The uterine contraction frequency was observed 10 minutes and 6 hours after insemination over a four-minute period using B-mode ultrasonography.
- Finally, pregnancy rates were evaluated 16 days after insemination.
Results and Findings
- The research found that seminal plasma presence decreases the frequency of uterine contractions in the mares from Group 1.
- Simultaneously, an increased level of PMNs (polymorphonuclear neutrophils, a type of white blood cell that helps fight infection) was found in the lavage fluid in the mares inseminated with seminal plasma, indicating more inflammation.
- It’s noteworthy that the pregnancy rates remained the same in both groups, at 62%.
Conclusions
- This study suggests that the presence of seminal plasma during breeding lowers uterine contractility and enhances the uterus’ inflammatory response to semen. However, it does not seem to affect the pregnancy rates.
- Mares developing persistent mating-induced endometritis might have inherently weak uterine contractility and compromised uterine clearance. Therefore, for such mares, it might be unsuitable to have seminal plasma during breeding.
- The researchers concluded that further studies are required to understand the role of seminal plasma in mares experiencing difficulties.
Cite This Article
APA
Portus BJ, Reilas T, Katila T.
(2005).
Effect of seminal plasma on uterine inflammation, contractility and pregnancy rates in mares.
Equine Vet J, 37(6), 515-519.
https://doi.org/10.2746/042516405775314844 Publication
Researcher Affiliations
- MTT Agrifood Research Finland, Animal Production Research, Equines, 32100 Ypäjä, Finland.
MeSH Terms
- Animals
- Breeding
- Endometritis / etiology
- Endometritis / immunology
- Endometritis / veterinary
- Endometrium / immunology
- Female
- Horse Diseases / etiology
- Horse Diseases / immunology
- Horses
- Insemination, Artificial / methods
- Insemination, Artificial / veterinary
- Male
- Neutrophils
- Pregnancy
- Pregnancy Rate
- Semen / immunology
- Semen / physiology
- Seminal Plasma Proteins / immunology
- Seminal Plasma Proteins / pharmacology
- Spermatozoa / physiology
- Uterine Contraction / drug effects
- Uterine Contraction / physiology
Citations
This article has been cited 7 times.- Bazzano M, Zhu C, Laus F, Giambattista AD, Laghi L. Exploring the metabolome of seminal plasma in two different horse types: Light versus draft stallions. Reprod Domest Anim 2023 Jan;58(1):109-116.
- Morrell JM, Rocha A. A Novel Approach to Minimising Acute Equine Endometritis That May Help to Prevent the Development of the Chronic State. Front Vet Sci 2021;8:799619.
- Rivera Del Alamo MM, Reilas T, Lukasik K, Galvão AM, Yeste M, Katila T. Inflammatory Markers in Uterine Lavage Fluids of Pregnant, Non-Pregnant, and Intrauterine Device Implanted Mares on Days 10 and 15 Post Ovulation. Animals (Basel) 2021 Dec 8;11(12).
- Badrakh D, Yanagawa Y, Nagano M, Katagiri S. Effect of seminal plasma infusion into the vagina on the normalization of endometrial epidermal growth factor concentrations and fertility in repeat breeder dairy cows. J Reprod Dev 2020 Apr 10;66(2):149-154.
- Siemieniuch MJ, Szóstek AZ, Gajos K, Kozdrowski R, Nowak M, Okuda K. Type of Inflammation Differentially Affects Expression of Interleukin 1β and 6, Tumor Necrosis Factor-α and Toll-Like Receptors in Subclinical Endometritis in Mares. PLoS One 2016;11(5):e0154934.
- Alfatlawy HJ. Microbial profile of post-breeding endometritis in Arabian mares from the Al-Hira District, Iraq. Open Vet J 2025;15(8):3670-3676.
- Seyedasgari F, Asadi B, Kim E. Seminal plasma modulates post-thaw longevity and motility of frozen sperm in dromedary camel. Anim Biosci 2023 Dec;36(12):1821-1830.
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