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Vertebrate reproductive science and technology
REVIEW

Perspectives on the development and incorporation of assisted reproduction in the equine industry

E. L. Squires https://orcid.org/0000-0002-4569-2886
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Reproductive Management, 5536 North County Road 3, Fort Collins, CO 80524, USA. Email: edward.squires@uky.edu

Reproduction, Fertility and Development 31(12) 1753-1757 https://doi.org/10.1071/RD19365
Submitted: 24 July 2019  Accepted: 23 October 2019   Published: 15 November 2019

Abstract

Marked changes in equine breeding technologies have occurred over the past 25 years. Although there have been numerous reviews on assisted reproduction techniques for horses, few publications include the acceptance and impact of these techniques on the horse industry. In this review, several techniques are discussed, with an emphasis on how they developed in the horse industry and altered equine reproductive medicine. Embryo transfer has become a widely used technology, allowing multiple foals to be produced per year. Embryos can be collected, cooled or frozen, and shipped to a distant facility for transfer into recipient mares. Failure to obtain embryos from some mares stimulated the development of oocyte collection and transfer. Oocyte technologies became more practical when intracytoplasmic sperm injection was developed in the early 2000s. There are now facilities across the world that routinely produce embryos in vitro. Cryopreservation of oocytes has lagged because of limited success, but embryo cryopreservation is commonplace. Techniques such as sex-sorted semen, superovulation and genetic diagnosis of embryos are not widely used, and they will require more development before they are established in the horse industry in a cost-efficient manner.

Additional keywords: assisted reproductive technology, embryo transfer, intracytoplasmic sperm injection, ovum pick-up, superovulation.


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