Preimplantation Genetic Testing (PGT) in horses is a technique that allows for the examination of horse embryos before they are implanted in the uterus. This procedure is possible by embryo biopsy, involving careful extraction of a few cells from the outer layer of the embryo, typically on day 6 or 7 after fertilization.

The extracted cells undergo DNA testing that can determine the sex of the embryo, identify coat color variants, and screen for genetic diseases. Therefore, by integrating PGT into reproductive strategies, breeders can make decisions that promote the welfare of the horses and maximize the potential for a healthy foal.