Abstract: Insemination of mares with frozen-thawed spermatozoa requires intensive management and results in 40%-60% per cycle pregnancy rates. Objective: To determine if satisfactory fertility is possible for frozen-thawed semen after processing it through a microfluidic device, followed by storage at 17°C for up to 24 h before fixed-time insemination. Methods: Uncontrolled field trials. Methods: A pilot study evaluated the motility of frozen-thawed spermatozoa after centrifugation and storage (17°C) in two different media for up to 48 h. Subsequently, the motility of frozen-thawed semen processed through a microfluidic device, resuspended in two different media during storage (17°C) for up to 24 h was evaluated. The fertility of frozen-thawed spermatozoa, after microfluidic sorting and storage at 17°C for up to 24 h, was evaluated after fixed-time insemination in a commercial embryo programme. Experiment 1: Frozen-thawed spermatozoa (N = 5 stallions) were centrifuged and resuspended in Botusemen Gold™ or SpermSafe™ and stored (17°C) for up to 48 h. Sperm motility was evaluated by CASA at 0, 6, 24 and 48 h. Experiment 2: Frozen-thawed spermatozoa (N = 4 stallions) underwent microfluidic sorting and storage (17°C) for up to 24 h in both media. Sperm concentration and motility were evaluated at 0, 16 and 24 h. Experiment 3: Fertility of frozen-thawed spermatozoa (N = 3 stallions) was evaluated after insemination of 42 mare cycles at 6, 16 and 24 h after thawing, microfluidic sorting and storage before fixed-time insemination. Results: The stallion significantly influenced sperm motility, but there was no effect of media on motility parameters. Storage time significantly affected sperm motility after centrifugation but not after microfluidic sorting. Storage time had no effect on the overall embryo recovery rate (52%, n = 42). Conclusions: Field trial with small mare numbers and no control at time = 0 h. Conclusions: Fixed-time insemination of frozen-thawed spermatozoa after microfluidic sorting and storage at 17°C for up to 24 h produced satisfactory embryo recovery rates.
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.
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.
This research study explores the possibility of achieving satisfactory fertility in horses using frozen-thawed spermatozoa. The sperm is processed through a microfluidic device and then stored at 17°C for up to 24 hours before a fixed-time insemination.
Objective of the Study
The main aim of this research is to verify if satisfactory fertility can be achieved using frozen-thawed stallion spermatozoa, which has been processed through a microfluidic device and stored at 17°C for up to 24 hours.
Study Methodology
The study involved uncontrolled field trials to evaluate the motility of the frozen-thawed spermatozoa under different conditions.
The research was conducted in three experiments. The first experiment evaluated the motility of frozen-thawed stallion spermatozoa after centrifugation and storage in two different media for up to 48 hours. The second experiment assessed frozen-thawed semen processed via a microfluidics device and stored in different media for up to 24 hours. The last experiment examined the fertility of stallion’s frozen-thawed spermatozoa after being stored at 17°C for up to 24 hours, followed by fixed-time insemination in a commercial embryo program.
Results and Conclusion
The results found that different stallions influenced sperm motility, but the media used for storage did not affect motility parameters.
The storage time impacted the motility of sperm after centrifugation but did not affect it post-microfluidic sorting.
The storage time also had no influence on the overall embryo recovery rate, standing at 52% out of 42 mare cycles tested.
In conclusion, the study suggests that it is possible to achieve satisfactory embryo recovery rates by fixed-time insemination of frozen-thawed spermatozoa (processed through microfluidic sorting and stored at 17°C for up to 24 hours).
Cite This Article
APA
Morris L, Harteveld R, Gibb Z.
(2024).
A simplified fixed-time insemination protocol using frozen-thawed stallion spermatozoa stored at 17°C for up to 24 h before insemination.
Equine Vet J.
https://doi.org/10.1111/evj.14096
Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, University of Newcastle, Australia.
Grant Funding
3/2021 / New Zealand Equine Research Foundation
References
This article includes 32 references
Squires E, Barbacini S, Matthews P, Byers W, Schwenzer K, Steiner J. Retrospective study of factors affecting fertility of fresh, cooled and frozen semen.. Equine Vet Educ 2006;18:96–99.
Hollinshead FK, Hanlon DW. A single fixed‐time insemination prior to ovulation results in higher pregnancy rates than post‐ovulation insemination when using frozen‐thawed semen.. J Equine Vet 2018;66:198–199.
Sabatini C, Rota A, Panzani D, Tesi M, Camillo F. Postmating endometritis and pregnancy rate were not affected by the addition to frozen‐thawed semen of filtered seminal plasma when mares without evidence of endometritis were artificially inseminated once 40 hours post‐gonadotropin‐releasing hormone treatment.. J Equine Vet 2018;62:54–59.
Prell MJ, McCue PM, Moffett PD, Graham JK. Motility and fertility evaluation of thawed frozen stallion semen after 24 hours of cooled storage.. J Equine Vet 2020;90:102983.
Luhr J, Oldenhof H, Bigalk J, Martinsson G, Burger D, Sieme H. Evaluation of fertilization capacity of cryopreserved stallion sperm, directly after thawing and after cooled storage.. J Equine Vet 2018;66:72.
Clulow J, Gibb Z. Liquid storage of stallion spermatozoa—past, present and future.. Anim Reprod Sci 2022;247:107088.
Ricker JV, Linfor JJ, Delfino WJ, Kysar P, Scholtz EL, Tablin F. Equine sperm membrane phase behavior: the effects of lipid‐based cryoprotectants.. Biol Reprod 2006;74(2):359–365.
Felix MR, Hinrichs K. Selection of frozen‐thawed semen for standard in vitro fertilization.. J Equine Vet 2023;125:104648.
Rappa KL, Rodriguez HF, Hakkarainen GC, Anchan RM, Mutter GL, Asghar W. Sperm processing for advanced reproductive technologies: where are we today?. Biotechnol Adv 2016;34:578–587.
Cuervo‐Arango J, Nivola K, Väihkönen L, Katila T. The effect of storage temperature of stallion semen on pregnancy rates.. J Equine Vet 2015;35:611–616.
Gibb Z, Clulow JR, Maclellan LJ, Morris LHA, Aitken RJ, Swegen A. Storing stallion sperm in SpermSafe™ at 17°C may improve fertility by reducing mPTP formation.. J Equine Vet 2023;125:104589.