Embryonic transfer is the process by which a mare can carry a foal that is actually the result of a mating between a stallion and a different mare altogether. For the sake of this explanation, let’s say that your mare is a world-class, perfectly conformed competitor with an excellent disposition. You would love to reproduce all of her qualities, but you just can’t let her take the time out of the show schedule to carry a foal, give birth, and be reconditioned – altogether many months.
And if you wait to breed her, you are afraid her age may become an issue. You also may not want to risk a pregnancy for fear of complications.
No matter what method you choose to breed your mare, you need to be prepared. AQHA's "Equine Breeding Techniques and Foal Health" report prepares you not only for the breeding, but for the care of the foal once it hits the ground.
In the embryonic transfer process, the veterinarian inseminates your mare with the semen of the stallion you have chosen, and a week or so later, the embryo is “flushed” from her uterus and transplanted into another mare. The “recipient” mare carries your new foal while you and the actual mother continue with your busy show season. When the foal is born, DNA testing confirms that the dam is the mare that was inseminated, and the foal is properly registered. Let’s say you really get greedy and want 10 foals out of your mare in one year. Depending on the fertility of your mare, you could feasibly implant 10 different mares, and come spring, have 10 new foals out of your favorite mare while she never missed a beat or a blue ribbon. Approximately 6 to 8 days after ovulation, the fertilized egg is removed via a catheter, and its condition and quality is checked. Then, either by surgical insertion into the uterine horn, or by transcervical insertion using a pipette, the fertilized egg is transplanted into the recipient mare. This should be a healthy, proven broodmare. I do not recommend using a maiden mare (one that never carried a foal). After the embryo is transplanted, the recipient mare must be checked regularly via ultrasound to see how it continues to develop. This procedure demands a highly trained vet who is up-to-date on all the latest advances in equine reproduction. The process should then become that of a normal pregnancy. If you are considering this method, there are questions you should ask your vet:
- Are you trained and equipped for the process of embryo transfer?
- What exactly are the medical procedures involved?
- What are the costs involved?
- Is my mare a good candidate for this procedure?
- Will any of this process be harmful to my mare?
- Will any of this process harm the recipient mare?
- What is the success rate with this procedure?