Mobility of the early equine conceptus.
Abstract: Movement of the conceptus within the uterine lumen of barren mares was studied by daily ultrasound examinations on days 11-20 and by rectal palpation on days 15-48 (Experiment 1) and by ultrasound examinations 3 or 4 times per day at 2-4 hour intervals on days 11-16 (Experiment 2). In addition, broodfarm records were analyzed to compare side of ovulation with side of embryo attachment (Experiment 3). The vesicle was found in opposite uterine horns for 43% of the successive, daily, ultrasound examinations on days 11 and 12, 12 and 13, 13 and 14, and 14 and 15; 24% of the successive examinations on days 15 and 16; and 8% on days 16 and 17. No movement was detected after day 17. The vesicle was found in opposite horns during 41% of the successive examinations at 2-4 hour intervals on days 11, 12, 13, 14, and 15, but no movement was detected on day 16. In addition, no transuterine migration was found by rectal palpation between the day of first detection of an embryonal enlargement (mean, day 17) and day 48. During ultrasound examination on days 11-15, the vesicle was found significantly more frequently in the left horn (66% of the observations) than in the right horn (34%); however, final attachment occurred more frequently in the right horn (63% of the mares). In analyses of brood-farm records, ovulation occurred with equal frequency in left and right ovaries in barren and lactating mares, but with significantly greater frequency in the left ovary (63%) in maiden mares. Regardless of the side of ovulation, final attachment of the conceptus occurred significantly more frequently in the right horn (66%) in barren and maiden mares, but not in lactating mares.
Publication Date: 1983-04-01 PubMed ID: 16725808DOI: 10.1016/0093-691x(83)90180-2Google Scholar: Lookup
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- Journal Article
Summary
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The research article investigates the movement of the early equine embryo within the uterus. Through a series of experiments and analysis, the researchers found notable rates of transuterine migration during the initial developmental stages, but observed no movement after day 17, with final attachment of the embryo mostly occurring in the right uterine horn.
Experimental Overview
The study consisted of three main experiments:
- Experiment 1 involved daily ultrasound examinations on mares between days 11-20 and by rectal palpation from days 15-48. The goal was to track the movement of the conceptus within the uterus over time.
- Experiment 2 was a more intensive version of Experiment 1, entailing ultrasound examinations 3 or 4 times per day at 2-4 hour intervals, in order to observe any smaller-scale changes not captured in the first experiment.
- Experiment 3 involved a review of broodfarm records to determine if the side of ovulation correlated with the side of embryo attachment.
Key Observations
A number of key findings emerged from each of the experiments:
- In Experiment 1 and 2, the researchers noted that the vesicle (fluid-filled structure that will develop into the embryo) was found in opposite uterine horns in 43% of the daily ultrasound examinations on days 11 to 15, and in 41% of more frequent examinations. However, no movement was detected after day 17, indicating that this transuterine movement is time-limited.
- Palpation results revealed no transuterine migration from the day of first detection of an embryonal enlargement (average day 17) until day 48.
- In Experiment 3, the analysis of broodfarm records indicated that while ovulation occurred equally in left and right ovaries, final attachment of the conceptus occurred more often in the right horn (66%) in both barren and maiden mares, but not in lactating mares.
Conclusions
The research found that mobility of the early equine conceptus is common, with notable transuterine migration until approximately day 17 of development. Importantly, despite this initial mobility, final attachment most commonly occurs in the right uterine horn. These findings can be valuable in understanding equine reproductive processes, enabling more informed attempts at breeding and resolving fertility issues.
Cite This Article
APA
Ginther OJ.
(1983).
Mobility of the early equine conceptus.
Theriogenology, 19(4), 603-611.
https://doi.org/10.1016/0093-691x(83)90180-2 Publication
Researcher Affiliations
- Department of Veterinary Science, University of Wisconsin, Madison, WI 53706, USA.
Citations
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- Segabinazzi LGTM, Roberts BN, Peterson EW, Ambrosia R, Bergfelt D, Samper J, French H, Gilbert RO. Early Pregnancy in Jennies in the Caribbean: Corpus Luteum Development and Progesterone Production, Uterine and Embryo Dynamics, Conceptus Growth and Maturation. Animals (Basel) 2022 Jan 6;12(2).
- 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).
- Klein C, Bruce P, Hammermueller J, Hayes T, Lillie B, Betteridge K. Transcriptional profiling of equine endometrium before, during and after capsule disintegration during normal pregnancy and after oxytocin-induced luteostasis in non-pregnant mares. PLoS One 2021;16(10):e0257161.
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- Klohonatz KM, Coleman SJ, Islas-Trejo AD, Medrano JF, Hess AM, Kalbfleisch T, Thomas MG, Bouma GJ, Bruemmer JE. Coding RNA Sequencing of Equine Endometrium during Maternal Recognition of Pregnancy. Genes (Basel) 2019 Sep 25;10(10).
- Klohonatz KM, Nulton LC, Hess AM, Bouma GJ, Bruemmer JE. The role of embryo contact and focal adhesions during maternal recognition of pregnancy. PLoS One 2019;14(3):e0213322.
- Takahashi H, Haneda S, Kayano M, Matsui M. Differences in progesterone concentrations and mRNA expressions of progesterone receptors in bovine endometrial tissue between the uterine horns ipsilateral and contralateral to the corpus luteum. J Vet Med Sci 2016 May 3;78(4):613-8.
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- Drews B, Roellig K, Menzies BR, Shaw G, Buentjen I, Herbert CA, Hildebrandt TB, Renfree MB. Ultrasonography of wallaby prenatal development shows that the climb to the pouch begins in utero. Sci Rep 2013;3:1458.
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- de Castro T, van Heule M, Domingues RR, Jacob JCF, Daels PF, Meyers SA, Conley AJ, Dini P. Embryo-endometrial interaction associated with the location of the embryo during the mobility phase in mares. Sci Rep 2024 Feb 7;14(1):3151.
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