Advanced reproductive technologies that can be used in horses are expanding every year. Geography is no longer a limiting factor in choosing a mate for your mare, as fresh cooled semen can be shipped across North America with ease. Frozen semen also means stallions from other continents can be used. Frozen semen allows for the continued breeding of a stallion even after he dies (for those breeds that allow it). Embryo transfer–once uncommon and expensive–is now commonplace and relatively affordable. These techniques allow horse breeders more options for their breeding programs, and are helping preserve endangered species. In this article, we will discuss the ins and outs of embryo transfer, the success rates, and the approximate costs involved.

A Brief History

Embryo transfer is the removal of a six- to eight-day-old embryo from one mare and the transfer of it into a recipient mare's uterus to continue development. This procedure has been performed in the United States since the mid-1970s, and the recovery of the embryos has changed very little in the last 15 years. However, new procedures are being used for the implantation of the embryo, which will be discussed later.

With the approval of several breed associations to register foals from embryo transfer, the demand and success of embryo transfer has grown