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Reproduction in domestic animals = Zuchthygiene2024; 59 Suppl 2; e14625; doi: 10.1111/rda.14625

Equine ART and antral follicle count: Can we deepen our understanding to improve outcomes?

Abstract: Assisted reproductive technologies (ARTs) are performed worldwide in the equine industry to produce genetically valuable foals. Among them, ovum pick up (OPU) combined with intra-cytoplasmic sperm injection (ICSI) can now be more efficient than embryo transfer (ET) under optimal conditions. However, OPU is not a benign procedure for the mare and the process is costly. Improved efficiency is therefore in the interest of everyone, maximizing mare welfare and optimizing economics for the client. One of the key factors of success is the antral follicle count (AFC) at the time of OPU and subsequently the number of oocytes obtained. Variations in AFC are reported between individuals and between geographical areas. This leads to a significant increase in numbers of embryos produced per session in some countries compared to others, independent of the laboratory efficiency. This article revisits the basics of folliculogenesis involved in establishment of the antral follicle population and explores work in other species given the paucity of equine research in this area. The aim of the review is to elucidate interesting areas of further research that could generate essential information for clinicians and clients about the management and selection of the donor mare for OPU and potentially identify pharmacological targets for manipulation.
© 2024 The Author(s). Reproduction in Domestic Animals published by Wiley‐VCH GmbH.
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Publication Date: 2024-09-05 PubMed ID: 39233592DOI: 10.1111/rda.14625Google Scholar: Lookup
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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 article discusses the role of equine Assisted Reproductive Technologies (ARTs), specifically ovum pick up (OPU) combined with intra-cytoplasmic sperm injection (ICSI), in improving reproduction efficiency in horses. The study also explores the impact of antral follicle count (AFC) on the success of OPU and suggests potential areas of future research.

Assisted Reproductive Technologies in Horses

  • This study focuses on the use of Assisted Reproductive Technologies, especially OPU and ICSI, in the equine industry. These procedures are performed worldwide with the intention of producing genetically valuable offspring.
  • The researchers note that OPU, when combined with ICSI, can sometimes be more efficient than embryo transfer (ET) in ideal conditions. However, they note that OPU, the process of extracting eggs directly from the horse’s ovaries, is not a harmless procedure and can be costly, indicating a need for improved efficiency for the sake of animal welfare and economics.

Antral Follicle Count and OPU Success

  • The study identifies the AFC at the time of OPU as a major factor influencing the number of oocytes and consequently the success rate of the procedure. The AFC varies among individual horses and between different geographical areas.
  • This variation results in a significant increase in the number of embryos produced per procedure in some countries compared to others, independently of laboratory efficiency, suggesting a linkage between AFC and ART success in horses.

Suggestions for Future Research

  • The article also examines the principles of folliculogenesis (the process of ovary follicle development) that contribute to the establishment of the antral follicle population.
  • The researchers admit a lack of extensive equine-specific research in this area and turn to insights from studies on other species.
  • The review aims to identify potentially interesting areas for future research, such as better donor mare selection for OPU, and possible pharmacological targets for manipulation to enhance the AFC. Such research could generate crucial knowledge for both clinicians and clients involved in equine ARTs.

Cite This Article

APA
Le Breton A, Lewis N. (2024). Equine ART and antral follicle count: Can we deepen our understanding to improve outcomes? Reprod Domest Anim, 59 Suppl 2, e14625. https://doi.org/10.1111/rda.14625

Publication

Reproduction in domestic animals = Zuchthygiene
ISSN: 1439-0531
NlmUniqueID: 9015668
Country: Germany
Language: English
Volume: 59 Suppl 2
Pages: e14625

Researcher Affiliations

Le Breton, Aurore
  • School of Veterinary Medicine, University College Dublin, Dublin, Ireland.
Lewis, Niamh
  • School of Veterinary Medicine, University College Dublin, Dublin, Ireland.

MeSH Terms

  • Horses / physiology
  • Animals
  • Ovarian Follicle
  • Female
  • Reproductive Techniques, Assisted / veterinary
  • Oocytes / physiology
  • Sperm Injections, Intracytoplasmic / veterinary
  • Sperm Injections, Intracytoplasmic / methods
  • Embryo Transfer / veterinary
  • Embryo Transfer / methods
  • Oocyte Retrieval / veterinary
  • Oocyte Retrieval / methods
  • Pregnancy

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Citations

This article has been cited 3 times.
  1. Márquez-Moya A, Carreras-Vico N, Sala-Ayala L, Martínez-Boví R, Cuervo-Arango J. Comparative Evaluation of Follicular Flushing Frequency and Scraping Time During Ovum Pick-Up in Mares: Effects on Oocyte Recovery Rate and Technical Considerations. Reprod Domest Anim 2026 Feb;61(2):e70183.
    doi: 10.1111/rda.70183pubmed: 41674388google scholar: lookup
  2. Van den Branden E, Salamone M, Broothaers K, Peere S, Polfliet E, Dewulf M, Van Steenkiste G, van Loon G, Smits K, Govaere J. Physiological and behavioral parameters of pain and stress in mares during and after transvaginal ultrasound-guided follicular aspiration. Front Vet Sci 2025;12:1574351.
    doi: 10.3389/fvets.2025.1574351pubmed: 40271484google scholar: lookup
  3. Gambini A, Smith JM, Gurkin RJ, Palacios PD. Current and Emerging Advanced Techniques for Breeding Donkeys and Mules. Animals (Basel) 2025 Mar 29;15(7).
    doi: 10.3390/ani15070990pubmed: 40218383google scholar: lookup
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