The Influence of Aspiration Pressure, Follicle Flushing Method and Needle Rotation During Single-Operator OPU Technique on Oocyte Recovery and Embryo Production in the Mare.
Abstract: The objective of this study was to determine the effect of two aspiration pressures (75 vs. 150 mmHg), the follicle flushing method (injection pump controlled by a foot pedal vs. a plastic syringe) and the twisting of the OPU needle on oocyte recovery and in vitro embryo production. OPU data from a total of 104 warmblood sport mares belonging to a commercial OPU-ICSI program were collected as part of a prospective study split into three experiments. Each mare was used only once for OPU. In Experiment 1, the mares' follicles were aspirated using either a high aspiration pressure (flow rate of 1.33 mL/s; = 18) or low aspiration pressure (0.75 mL/s; = 18); in Experiment 2, follicles were flushed using either a manual method (plastic syringe, = 18) or an automatic method (injection pump controlled by a foot pedal, = 18); and in Experiment 3, the follicles were aspirated by scraping the follicle wall with needle rotation (needle twisting, = 16) or without needle rotation (control, = 16). In all the experiments, the same OPU operator and technician searching oocytes were used, and the allocation of each mare to the different treatment groups was randomized. The overall mean oocyte recovery rate of the study was 54.2 ± 17.1%, and the mean number of embryos per OPU-ICSI session was 1.9 ± 1.6. The oocyte recovery rate was not influenced by any of the parameters investigated ( > 0.05). However, high aspiration pressure (150 mmHg) tended to yield oocytes with lower maturation (51.6%; = 0.09) and blastocyst rates (20.6%; = 0.08) following IVM and ICSI, respectively, compared with the low aspiration group (64.4% MII rate and 31.4% blastocyst rate). In conclusion, increasing aspiration pressure does not increase oocyte recovery. Furthermore, when a single operator performs the OPU (holding the ovary and handling the needle simultaneously), needle rotation to scrape the follicle wall does not improve oocyte recovery.
Publication Date: 2025-03-14 PubMed ID: 40150362PubMed Central: PMC11939359DOI: 10.3390/ani15060832Google Scholar: Lookup
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Summary
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The research tested different methods of oocyte recovery and embryo production in sport mares to determine which were most effective. The specific technique variables examined were aspiration pressure, follicle flushing methods, and needle rotation during OPU technique. In general, the results found that neither increasing aspiration pressure nor using needle rotation enhanced oocyte recovery rates.
Objective and Methodology of the Study
- The goal of this research was to evaluate the impacts of alterations in certain operational variables on oocyte recovery and in vitro embryo production. The variables scrutinized were aspiration pressure (two levels: 75 and 150 mmHg), method of follicle flushing (via foot pedal-controlled injection pump or plastic syringe) and twisting of the OPU needle.
- The data was gathered from 104 warmblood sport mares each only used once for oocyte pick-up (OPU). It was a prospective study broken down into three parts—each testing a different variable.
- All experiments were conducted by the same operator and oocyte locating technician to eliminate possible inter-operator variation.
Experiments and Findings
- In the first experiment, follicles were aspirated using high and low aspiration pressures, recorded at 1.33 mL/s and 0.75 mL/s, respectively. The second experiment compared follicle flushing methods—with a manual technique involving a plastic syringe and an automatic technique using a foot pedal-controlled injection pump. In the third experiment, some follicles were aspirated using an OPU needle rotated to scrape the follicle wall and in others, no needle rotation was applied.
- Despite changes in these operational variations, the overall mean oocyte recovery rate remained fairly steady at around 54.2%.
- However, experiments showed that employing a high aspiration pressure of 150 mmHg resulted in lower oocyte maturation and blastocyst rates compared to the low aspiration group. This suggests an optimal pressure level for highest oocyte maturation and blastocyst success.
- Additional findings illustrated that using a scraping motion with the OPU needle did not improve oocyte recovery rates.
Conclusion
- The findings concluded two main points—increasing aspiration pressure does not boost oocyte recovery and using a rotating OPU needle to scrape the follicle wall does not improve oocyte recovery rates.
- Given these outcomes, it was deduced that the most effective approach to oocyte recovery and in vitro embryo production should maintain a low aspiration pressure and not necessarily involve the scraping technique.
Cite This Article
APA
Cuervo-Arango J, Sala-Ayala L, Márquez-Moya A, Martínez-Boví R.
(2025).
The Influence of Aspiration Pressure, Follicle Flushing Method and Needle Rotation During Single-Operator OPU Technique on Oocyte Recovery and Embryo Production in the Mare.
Animals (Basel), 15(6), 832.
https://doi.org/10.3390/ani15060832 Publication
Researcher Affiliations
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Alfara del Patriarca, Valencia, Spain.
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Alfara del Patriarca, Valencia, Spain.
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Alfara del Patriarca, Valencia, Spain.
- Equine Fertility Group, Faculty of Veterinary Medicine, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Alfara del Patriarca, Valencia, Spain.
Conflict of Interest Statement
The authors declare no conflicts of interest.
References
This article includes 32 references
- Hinrichs K. In Vitro production of equine embryos: State of the art.. Reprod. Domest. Anim. 2010;45((Suppl. S2)):3–8.
- Galli C, Colleoni S, Duchi R, Lagutina I, Lazzari G. Developmental competence of equine oocytes and embryos obtained by in vitro procedures ranging from in vitro maturation and ICSI to embryo culture, cryopreservation and somatic cell nuclear transfer.. Anim. Reprod. Sci. 2007;98:39–55.
- Felix M.R., Turner R.M., Dobbie T., Hinrichs K. Successful in vitro fertilization in the horse: Production of blastocysts and birth of foals after prolonged sperm incubation for capacitation.. Biol. Reprod. 2022;107:1551–1564.
- Stout T.A.E. Clinical Application of in Vitro Embryo Production in the Horse.. J. Equine Vet. Sci. 2020;89:103011.
- Lazzari G, Colleoni S, Crotti G, Turini P, Fiorini G, Barandalla M, Landriscina L, Dolci G, Benedetti M, Duchi R. Laboratory Production of Equine Embryos.. J. Equine Vet. Sci. 2020;89:103097.
- Cuervo-Arango J, Claes A.N., Stout T.A.E. Mare and stallion effects on blastocyst production in a commercial equine ovum pick-up-intracytoplasmic sperm injection program.. Reprod. Fertil. Dev. 2019;31:1894–1903.
- Claes A, Stout T.A.E. Success rate in a clinical equine in vitro embryo production program.. Theriogenology 2022;187:215–218.
- Hinrichs K, Kenney R.M. A colpotomy procedure to increase oocyte recovery rates on aspiration of equine preovulatory follicles.. Theriogenology 1987;27:237.
- Vogelsang M.M., Kreider J.L., Bowen M.J., Potter G.D., Forrest D.W., Kraemer D.C. Methods for collecting follicular oocytes from mares.. Theriogenology 1988;29:1007–1018.
- Hawley L.R., Enders A.C., Hinrichs K. Comparison of Equine and Bovine Oocyte-Cumulus Morphology within the Ovarian Follicle.. Biol. Reprod. 1995;52:243–252.
- Márquez-Moya A., Sala-Ayala L., Carreras-Vico N., Martínez-Boví R., Cuervo-Arango J. Factors influencing oocyte recovery during ultrasound-guided follicle aspiration in mares: A postmortem study.. Theriogenology 2025;235:39–45.
- Sasamoto Y., Sakaguchi M., Katagiri S., Yamada Y., Takahashi Y. The effects of twisting and type of aspiration needle on the efficiency of transvaginal ultrasound-guided ovum pick-up in cattle.. J. Vet. Med. Sci. 2003;65:1083–1086.
- Bols P.E., Van Soom A., Ysebaert M.T., Van den heede J.M., de Kruif A. Effects of aspiration vacuum and needle diameter on cumulus oocyte complex morphology and developmental capacity of bovine oocytes.. Theriogenology 1996;45:1001–1014.
- Bols P.E., Ysebaert M.T., Van Soom A., de Kruif A. Effects of needle tip bevel and aspiration procedure on the morphology and developmental capacity of bovine compact cumulus oocyte complexes.. Theriogenology 1997;47:1221–1236.
- Ritchie W.A. Nuclear transfer in sheep.. Methods Mol. Biol. 2006;325:11–23.
- Galli C., Duchi R., Colleoni S., Lagutina I., Lazzari G. Ovum pick up, intracytoplasmic sperm injection and somatic cell nuclear transfer in cattle, buffalo and horses: From the research laboratory to clinical practice.. Theriogenology 2014;81:138–151.
- Colleoni S., Lagutina I., Lazzari G., Rodriguez-Martinez H., Galli C., Morrell J.M. New methods for selecting stallion spermatozoa for assisted reproduction.. J. Equine Vet. Sci. 2011;31:536–541.
- Rodríguez C., Anel L., Alvarez M., Anel E., Boixo J.C., Chamorro C.A., de Paz P. Ovum pick-up in sheep: A comparison between different aspiration devices for optimal oocyte retrieval.. Reprod. Domest. Anim. 2006;41:106–113.
- Sá M.A.F., Paiva S.O., Dutra G.A., Barbosa C.G., Mello M.R.B., Jacob J.C.F. Use of different pressures for transvaginal follicular aspiration in mares.. Arq. Bras. Med. Vet. Zootec. 2017;69:529–534.
- Brüssow K.P., Torner H., Rátky J., Hunter M.G., Nürnberg G. Ovum pick up in swine: The influence of aspiration vacuum pressure on oocyte recovery from preovulatory follicles.. Acta Vet. Hung. 1997;45:189–196.
- Ferré L.B., Alvarez-Gallardo H., Romo S., Fresno C., Stroud T., Stroud B., Lindsey B., Kjelland M.E. Transvaginal ultrasound-guided oocyte retrieval in cattle: State-of-the-art and its impact on the in vitro fertilization embryo production outcome.. Reprod. Domest. Anim. 2023;58:363–378.
- Foss R., Ortis H., Hinrichs K. Effect of potential oocyte transport protocols on blastocyst rates after intracytoplasmic sperm injection in the horse.. Equine Vet. J. Suppl. 2013;45:39–43.
- Sala-Ayala L., Pytel A.T., Stychno K., Cuervo-Arango J. Use of excised ovaries for oocyte recovery by ultrasound guided follicular aspiration—Validation of an experimental model for research purposes in live mares ovum pick up.. Theriogenology 2024;228:9–16.
- Claes A., Cuervo-Arango J., van den Broek J., Galli C., Colleoni S., Lazzari G., Deelen C., Beitsma M., Stout T.A. Factors affecting the likelihood of pregnancy and embryonic loss after transfer of cryopreserved in vitro produced equine embryos.. Equine Vet. J. 2019;51:446–450.
- Cortez J.V., Hardwicke K., Cuervo-Arango J., Grupen C.G. Cloning horses by somatic cell nuclear transfer: Effects of oocyte source on development to foaling.. Theriogenology 2023;203:99–108.
- Cuervo-Arango J., Claes A.N., Beitsma M., Stout T.A.E. The Effect of Different Flushing Media Used to Aspirate Follicles on the Outcome of a Commercial Ovum Pickup-ICSI Program in Mares.. J. Equine Vet. Sci. 2019;75:74–77.
- Lazzari G., Colleoni S., Barandalla M., Benedetti M., Duchi R., Galli C. 57° Influence of donor mare age on pre- and postimplanation embryo development within an equine ovum pick-up-intracytoplasmic sperm injection-embryo transfer (OPU-ICSI-ET) program over a three-year period.. Reprod. Fertil. Dev. 2021;34:264.
- Papas M., Govaere J., Peere S., Gerits I., Van de Velde M., Angel-Velez D., De Coster T., Van Soom A., Smits K. Anti-Müllerian Hormone and OPU-ICSI Outcome in the Mare.. Animals 2021;11:2004.
- Ramírez-Agámez L., Hernández-Avilés C., Whitfield-Cargile C.M., Coleman M.C., Love C.C. Treatment of mares with the non-steroidal anti-inflammatory drug (NSAID) phenylbutazone transiently affects in vitro maturation of equine oocytes and blastocyst development after Intracytoplasmic Sperm Injection (ICSI). Theriogenology 2024;223:53–58.
- Walbornn S.R., Felix M., Schnobrich M.R., Bradecamp E.A., Scoggin C.F., Stefanovski D., Hinrichs K. Effect of day of estrus cycle at time of transvaginal follicle aspiration for oocyte recovery on rates of in vitro maturation and blastocyst production after intracytoplasmic sperm injection.. J. Am. Vet. Med. Assoc. 2022;260:1683–1689.
- Dobbie T., Felix M.R., Gleason K., Hinrichs K. Transvaginal aspiration, oocyte maturation and production of blastocysts and a pregnancy via ICSI in an endangered breed: Baudet du Poitou donkey.. Theriogenology 2024;224:34–40.
- Martin-Pelaez S., Fuente A., Takahashi K., Perez I.T., Orozco J., Okada C.T.C., Neto C.R., Meyers S., Dini P. IVF with frozen-thawed sperm after prolonged capacitation yields comparable results to ICSI in horses: A morphokinetics study.. Theriogenology 2025;232:39–45.
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