Directional freezing of equine semen in large volumes.
- Journal Article
Summary
This study examines how a novel method of freezing horse semen called multi-thermal gradient (MTG) proves more effective than the conventional controlled-rate cryopreservation method (CRCM), in terms of the sperm’s post-thaw motility, viability, and membrane integrity.
Objective of the Research
The researchers aimed to improve the process of freezing equine semen, which has been a challenge in the horse industry because conventional methods resulted in a reduction in pregnancy rate and an increase in cost per pregnancy. The new method being evaluated was multi-thermal gradient (MTG) freezing, which was compared against the conventional controlled-rate cryopreservation method (CRCM).
Methodology
- 97 ejaculates with 50% or higher motility were collected from 31 stallions. Each sample was divided into two; one was frozen using MTG, and the other by CRCM.
- After freezing, the samples were stored in liquid nitrogen until they were thawed for evaluation.
- The efficacy of both methods was evaluated using three criteria: progressive linear motility (PLM), viability stain, and hypoosmotic swelling (HOS) test.
Results
- Among the samples frozen by MTG, 88% had a post-thaw PLM of at least 35%, whereas only 59% of the ejaculates frozen with CRCM reached such motility.
- Post-thaw evaluations for samples frozen by MTG and CRCM were: PLM – 50.2 +/- 1.5% and 37.4 +/- 1.5%, respectively; viability – 53.6 +/- 1.5% and 39.5 +/- 1.4%, respectively; and membrane integrity, as assessed by the HOS – 36.2 +/- 1.3% and 26.5 +/- 1.1%, respectively.
- The differences in outcomes based on all the evaluation methods were highly significant (p < 0.001), proving that MTG is superior to CRCM for freezing stallion semen.
Conclusion
The application of the MTG method of semen freezing in horses led to a significant improvement in post-thaw sperm health indicators compared to the traditional CRCM freezing method. This method could potentially impact the horse industry positively by lowering the cost per pregnancy and increasing pregnancy rates.
Cite This Article
Publication
Researcher Affiliations
- Institute of Animal Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel.
MeSH Terms
- Animals
- Cryopreservation / methods
- Cryopreservation / veterinary
- Female
- Fertility / physiology
- Horses / physiology
- Insemination, Artificial / veterinary
- Male
- Pregnancy
- Pregnancy Rate
- Random Allocation
- Semen Preservation / methods
- Semen Preservation / veterinary
- Sperm Count / veterinary
- Sperm Motility / physiology
- Spermatozoa / physiology
- Time Factors
Citations
This article has been cited 5 times.- 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.
- Bahari L, Bein A, Yashunsky V, Braslavsky I. Directional freezing for the cryopreservation of adherent mammalian cells on a substrate.. PLoS One 2018;13(2):e0192265.
- Saragusty J, Lemma A, Hildebrandt TB, Göritz F. Follicular size predicts success in artificial insemination with frozen-thawed sperm in donkeys.. PLoS One 2017;12(5):e0175637.
- Kim S, Hooper S, Agca C, Agca Y. Post-thaw ATP supplementation enhances cryoprotective effect of iodixanol in rat spermatozoa.. Reprod Biol Endocrinol 2016 Jan 29;14:5.
- Gil L, Galindo-Cardiel I, Malo C, González N, Alvarez C. Effect of Cholesterol and Equex-STM Addition to an Egg Yolk Extender on Pure Spanish Stallion Cryopreserved Sperm.. ISRN Vet Sci 2013;2013:280143.