Embryo Transfer — The New Age in Breeding

by Debra Ottier
Equine Research Centre
Guelph, Ontario, Canada

Although embryo transfer has been a common practice in the cattle industry for a number of years now, it has only recently gained steam in the equine world. Breed registries are now beginning to allow the use of embryo transfer in the registration of offspring as the development of blood typing and DNA parentage verification can prevent fraud and parentage errors. Thousands of embryos have been collected and transferred into recipient mares since the 1980s with the future looking towards the importation/exportation of viable embryos, rather than animals. This new age technology will have a tremendous impact on the equine industry today and in building the horse of tomorrow.

Embryo transfer allows for:

  • mares to continue performance careers,
  • outstanding mares to have more than one offspring per year,
  • obtain foals from problem and aged mares, and
  • immature two year olds to produce offspring.

The requirements are first to select a quality recipient mare to carry the foal to term. This mare needs to have a good reproductive history, be in good health with an adequate plan of nutrition. Both the donor mare and recipient mare need to be synchronized such that ovulation occurs approximately at the same time. This is where most problems arise, as attempts to synchronize the mares precisely can be difficult. The recipient mare must ovulate 24-48 hours after the donor mare, or progesterone levels are too high in the recipient.

Once the mares are synchronized, the donor mare is impregnated. The embryo is flushed at day seven after ovulation and transferred into the recipient by a surgical or non-surgical technique. Pregnancy, if established, is confirmed at day 17.

Armstrong Bros. in Inglewood, Ontario is the second largest breeder of Standardbreds in North America. With six resident stallions and nearly 200 broodmares, they have spent years perfecting the technique of embryo transfer and are now offering their services commercially to all breeds. Armstrong’s veterinarian, Cheryl Lopate, was trained in non-surgical embryo transfer and has a very high success rate with it.

You can expect to pay anywhere from $1,500 to $7,500 to lease or purchase a recipient mare. Costs for drugs for synchronization of ovulation, with professional fees payable to the veterinarian can amount to $2,000. Stabling fees for both the donor and the recipient, for a period of approximately 30 days, can add up quite quickly. One must not forget the stud fee that must be taken into account as well. In total, costs for embryo transfer range from $4,000 – $12,000.

Technology has advanced further so that embryos can be collected and preserved to enable shipping to a central facility which may have a large herd of recipient mares to choose from.

Although the equine industry lags behind in applying the tremendous advances in reproduction already made in other species, the time will eventually come when a catalogue of banked genetic material will be available to breeders to choose their next crop of potential equine athletes.