Pregnancies from vitrified equine oocytes collected from super-stimulated and non-stimulated mares.
Abstract: The objectives were to compare embryo development rates after transfer into inseminated recipients, vitrified thawed oocytes collected from super-stimulated versus non-stimulated mares. In vivo matured oocytes were collected by transvaginal, ultrasound guided follicular aspiration from super-stimulated and non-stimulated mares 24-26 h after administration of hCG. Oocytes were cultured for 2-4 h prior to vitrification. Cryoprotectants were loaded in three steps before oocytes were placed onto a 0.5-0.7 mm diameter nylon cryoloop and plunged directly into liquid nitrogen. Oocytes were thawed and the cryoprotectant was removed in three steps. After thawing, oocytes were cultured 10-12 h before transfer into inseminated recipients. Non-vitrified oocytes, cultured 14-16 h before transfer, were used as controls. More oocytes were collected from 23 non-stimulated mares (20 of 29 follicles), than 10 super-stimulated mares (18 of 88 follicles; P < 0.001). Of the 20 oocytes collected from non-stimulated mares, 12 were vitrified and 8 were transferred as controls. After thawing, 10 of the 12 oocytes were morphologically intact and transferred into recipients resulting in one embryonic vesicle on Day 16 (1 of 12 = 8%). Fourteen oocytes from super-stimulated mares were vitrified, and 4 were transferred as controls. After thawing, 9 of the 14 oocytes were morphologically intact and transferred into recipients resulting in two embryonic vesicles on Day 16 (2 of 14 = 14%). In control transfers, 7 of 8 oocytes from non-stimulated mares and 3 of 4 oocytes from super-stimulated mares resulted in embryonic vesicles on Day 16. The two pregnancies from vitrified oocytes resulted in healthy foals.
Publication Date: 2002-09-06 PubMed ID: 12212891DOI: 10.1016/s0093-691x(02)00920-2Google 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.
- Journal Article
- Research Support
- Non-U.S. Gov't
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 study investigates the rate of embryo development in horses through the use of two methods, super-stimulation and non-stimulation, to collect oocytes (a cell in an ovary which may undergo meiotic division to form an ovum). Embryo development rates were higher from non-stimulated mares compared to super-stimulated mares, and two healthy foals were successfully born from this process.
Objective of the Research
- The study aimed to compare the embryo development rates after the transfer of vitrified-thawed oocytes (egg cell that has been frozen and then thawed) collected from super-stimulated and non-stimulated mares.
- This method was compared to the traditional procedure of transporting non-vitrified oocytes, just after maturation, into inseminated recipients.
Research Methodology
- The researchers took mature, in vivo (within the living) oocytes from mares 24-26 hours after administering human Chorionic Gonadotropin (hCG) through follicular aspiration, a procedure to extract eggs from the ovaries. The mares were either super-stimulated or non-stimulated for this process.
- The oocytes were then cultured for 2-4 hours before vitrification, a process to freeze the cells.
- After vitrification and thawing, the oocytes were once again cultured, this time for 10-12 hours, before transfer into inseminated recipients.
- For the control group, non-vitrified oocytes after a 14-16 hour culture period were transferred.
Results of the Research
- Higher numbers of oocytes were collected from non-stimulated mares in comparison to super-stimulated mares.
- Ten of the 12 vitrified-thawed oocytes from non-stimulated mares were successfully transferred, resulting in one embryo development.
- For super-stimulated mares, 9 of the 14 vitrified-thawed oocytes were transferred, two of which resulted in embryonic development.
- The embryonic development rate in the control group was higher – seven out of eight in non-stimulated mares and three of four in super-stimulated mares.
- The development from vitrified oocytes resulted in the birth of two healthy foals.
Conclusion
- This study revealed that using vitrified-thawed oocytes might be a plausible technique for equine reproduction, and non-stimulated mares could provide more viable oocytes for this process.
- However, further research might be required for enhanced optimization due to the lower embryonic development rate in comparison to non-vitrified oocytes.
Cite This Article
APA
Maclellan LJ, Carnevale EM, Coutinho da Silva MA, Scoggin CF, Bruemmer JE, Squires EL.
(2002).
Pregnancies from vitrified equine oocytes collected from super-stimulated and non-stimulated mares.
Theriogenology, 58(5), 911-919.
https://doi.org/10.1016/s0093-691x(02)00920-2 Publication
Researcher Affiliations
- Department of Physiology, Colorado State University, Fort Collins 80523-1683, USA.
MeSH Terms
- Animals
- Cells, Cultured
- Cryopreservation
- Embryonic and Fetal Development
- Female
- Horses
- Insemination, Artificial / veterinary
- Oocytes / physiology
- Oocytes / transplantation
- Pregnancy
- Superovulation
- Tissue and Organ Harvesting / veterinary
Citations
This article has been cited 10 times.- Angel-Velez D, Meese T, Hedia M, Fernandez-Montoro A, De Coster T, Pascottini OB, Van Nieuwerburgh F, Govaere J, Van Soom A, Pavani K, Smits K. Transcriptomics Reveal Molecular Differences in Equine Oocytes Vitrified before and after In Vitro Maturation.. Int J Mol Sci 2023 Apr 7;24(8).
- Bolton RL, Mooney A, Pettit MT, Bolton AE, Morgan L, Drake GJ, Appeltant R, Walker SL, Gillis JD, Hvilsom C. Resurrecting biodiversity: advanced assisted reproductive technologies and biobanking.. Reprod Fertil 2022 Jul 1;3(3):R121-R146.
- Ortiz I, Dorado J, Pereira B, Diaz-Jimenez M, Consuegra C, Gosalvez J, Hidalgo M. DNA fragmentation of equine cumulus cells from Cumulus-Oocyte complexes submitted to vitrification and its relationship to the developmental competence of the oocyte.. Reprod Domest Anim 2022 Oct;57 Suppl 5(Suppl 5):64-67.
- Angel-Velez D, De Coster T, Azari-Dolatabad N, Fernandez-Montoro A, Benedetti C, Bogado Pascottini O, Woelders H, Van Soom A, Smits K. New Alternative Mixtures of Cryoprotectants for Equine Immature Oocyte Vitrification.. Animals (Basel) 2021 Oct 28;11(11).
- Tharasanit T, Thuwanut P. Oocyte Cryopreservation in Domestic Animals and Humans: Principles, Techniques and Updated Outcomes.. Animals (Basel) 2021 Oct 13;11(10).
- Benammar A, Derisoud E, Vialard F, Palmer E, Ayoubi JM, Poulain M, Chavatte-Palmer P. The Mare: A Pertinent Model for Human Assisted Reproductive Technologies?. Animals (Basel) 2021 Aug 4;11(8).
- Keros V, Fuller BJ. Cryopreservation of Mammalian Oocytes: Slow Cooling and Vitrification as Successful Methods for Cryogenic Storage.. Methods Mol Biol 2021;2180:437-454.
- Yi X, Zhou X, Yang Y, Dai J, Zhang D. [Effect of cryoprotectant removal by microfluidic chip on developmental capacity of oocytes].. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2018 Feb 25;35(1):123-130.
- Purohit GN, Meena H, Solanki K. Effects of Vitrification on Immature and in vitro Matured, Denuded and Cumulus Compact Goat Oocytes and Their Subsequent Fertilization.. J Reprod Infertil 2012 Jan;13(1):53-9.
- Prentice JR, Anzar M. Cryopreservation of Mammalian oocyte for conservation of animal genetics.. Vet Med Int 2010 Sep 21;2011.
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
