Pre-Implantation Genetic Testing

What is PGT?

Equine PGT (Preimplantation Genetic Testing) is a specialised reproductive technique used in horse breeding to screen embryos for genetic diseases, desirable traits, or sex before they are implanted in a recipient mare. It involves biopsying cells from a 6/7 day old embryo, commonly produced via ICSI or in vivo, to analyse DNA for genetic markers. Breeders can determine the foal's sex, screen for genetic disorders, and select for desired traits like coat colour, maximising breeding efficiency.

Requirements

The primary requirements for PGT involve strategic planning and regulatory compliance. You must first ensure your donor mare is healthy and that both parents have been genetically screened to identify which traits or diseases need testing. Logistically, you must coordinate with an approved veterinary team to perform the embryo collection and biopsy, often requiring the use of ICSI to produce the embryos in the first place. Financially, you need to budget for lab fees, shipping, and the maintenance of synchronized recipient mares. Finally, if you are in Ireland or the EU, you must ensure all animals have valid passports, are microchipped, and that all procedures are documented according to DAFM (Department of Agriculture) regulations to ensure the foals can be properly registered.

The advantage of PGT is the ability to guarantee a healthy, high-value foal before the pregnancy even begins. By screening embryos, you can eliminate the risk of devastating genetic diseases like WFFS or HYPP and select for specific marketable traits such as gender or coat colour. This precision significantly improves breeding efficiency by ensuring only viable, "normal" embryos are transferred, which reduces the rates of early pregnancy loss and the substantial costs associated with a "lost" breeding season. Ultimately, PGT protects your financial investment and reputation by ensuring every foal born is genetically sound and fits your specific breeding goals.

Advantages