Effect of type of semen, time of insemination relative to ovulation and embryo transfer on early equine embryonic vesicle growth as determined by ultrasound.
Abstract: Embryonic vesicle growth in the mare is easily monitored by ultrasound. Apart from pregnancy diagnosis, assessment of the embryonic vesicle in practice is also useful to evaluate its viability. Although subject to individual variation, embryo growth rate follows a constant pattern in the early stages of development in relation to embryonic age. Previous studies have shown a significant effect of some factors routinely used in practice, such as post-ovulation insemination and embryo transfer, on embryonic growth and the time in which the vesicle is first detected. This study attempts to confirm previous results in different settings and characterise the causes for this delay in growth. A total of 159 pregnancies from different mating protocols: (1) pre-ovulation natural mating, (2) pre-ovulation natural mating and transfer into recipient mares, (3) post-ovulation natural mating, and (4) post-ovulation AI with frozen/thaw spermatozoa were evaluated ultrasonographically from day 12 to 19 of pregnancy and vesicle diameters recorded. Regression analysis between embryonic vesicle diameters and embryonic ages was performed for each group and mean vesicle diameter at different age periods among groups were tested for statistical difference with a general linear model of variance. There was no significant difference between groups 1 and 2 (P=0.73) or between groups 3 and 4 (P=0.71). However both pre-ovulation groups (1 and 2) had larger vesicle diameters (P<0.000) at any embryonic age analysed than either of the post-ovulation groups (3 and 4). In conclusion, post-ovulation inseminations produced pregnancies with smaller vesicle diameters equivalent to approximately 1 day's growth.
Publication Date: 2009-02-26 PubMed ID: 19246082DOI: 10.1016/j.theriogenology.2008.12.020Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Comparative Study
- Evaluation Study
- Journal Article
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 research explores how different horse breeding protocols impact the growth of the embryonic vesicle, an early stage of equine pregnancy. It specifically looked at the timing of insemination in relation to ovulation, the type of semen used, and whether an embryo transfer takes place.
Research Context and Methodology
- This study builds on previous research exploring how certain commonly used breeding approaches can influence early equine pregnancy, specifically the growth of the embryonic vesicle (the fluid-filled structure that develops around the embryo).
- The research examines 159 pregnancies that were a result of four different mating protocols: pre-ovulation natural mating, pre-ovulation natural mating followed by transfer into surrogate mares, post-ovulation natural mating, and post-ovulation artificial insemination using thawed, frozen sperm.
- The presence and size of the embryonic vesicles in the resulting pregnancies were tracked via ultrasound from day 12 to day 19 of pregnancy, and the data was statistically analyzed to determine any effects of the different mating protocols on growth.
Main Findings
- Analysis of the data revealed no significant difference in embryonic vesicle size between pre-ovulation natural mating and pre-ovulation natural mating followed by embryo transfer. Similarly, no significant difference was found between post-ovulation natural mating and post-ovulation artificial insemination.
- However, it was discovered that the timing of insemination relative to ovulation had a significant impact on embryonic vesicle size. Specifically, vesicles were generally larger in pregnancies resulting from pre-ovulation inseminations (either natural or followed by transfer) compared to those resulting from post-ovulation inseminations (either natural or artificial).
- The decrease in vesicle size associated with post-ovulation insemination corresponded to roughly one day’s worth of growth, suggesting that the timing of insemination may delay early embryonic development.
Research Conclusion
- The research concluded that the timing of insemination in relation to ovulation plays a crucial role in the early development of equine pregnancy, represented by the size of the embryonic vesicle.
- Moreover, the study found no significant impact of the type of semen used (fresh or frozen-thawed) on early embryonic growth, nor of whether an embryo transfer took place after fertilization.
- Therefore, the researchers emphasized the importance of pre-ovulation insemination to achieve optimal embryonic vesicle growth, which should be further evaluated for potential impacts on pregnancy success rates and long-term health of the foals.
Cite This Article
APA
Cuervo-Arango J, Aguilar J, Newcombe JR.
(2009).
Effect of type of semen, time of insemination relative to ovulation and embryo transfer on early equine embryonic vesicle growth as determined by ultrasound.
Theriogenology, 71(8), 1267-1275.
https://doi.org/10.1016/j.theriogenology.2008.12.020 Publication
Researcher Affiliations
- Veterinary Clinical Science, Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, AL9 7TA Hatfield, UK. copicuervo@hotmail.com
MeSH Terms
- Animals
- Blastocyst / diagnostic imaging
- Blastocyst / ultrastructure
- Cytoplasmic Vesicles / physiology
- Embryo Transfer / methods
- Embryonic Development / physiology
- Female
- Horses / embryology
- Insemination, Artificial / methods
- Insemination, Artificial / veterinary
- Male
- Ovulation / physiology
- Pregnancy
- Semen / cytology
- Semen / physiology
- Semen Analysis
- Time Factors
- Ultrasonography
Citations
This article has been cited 3 times.- Morrell JM. Sperm Selection by Colloid Centrifugation. Methods Mol Biol 2025;2897:249-265.
- Ortiz-Rodriguez JM, Ortega-Ferrusola C, Gil MC, Martín-Cano FE, Gaitskell-Phillips G, Rodríguez-Martínez H, Hinrichs K, Álvarez-Barrientos A, Román Á, Peña FJ. Transcriptome analysis reveals that fertilization with cryopreserved sperm downregulates genes relevant for early embryo development in the horse. PLoS One 2019;14(6):e0213420.
- Lindahl J, Dalin AM, Stuhtmann G, Morrell JM. Stallion spermatozoa selected by single layer centrifugation are capable of fertilization after storage for up to 96 h at 6°C prior to artificial insemination. Acta Vet Scand 2012 Jul 12;54(1):40.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
