We offer high quality embryo transfer (ET) techniques. The technique developed more than two decades ago has evolved into a well accepted and successful procedure. Many horse registries accept embryo transfers, however, you should first contact your horse registry to get an update on their regulations before considering this procedure.

Embryo transfer has many advantages. It allows the production of foals from older sub-fertile mares and from mares that foaled late in the year. High performance mares can produce foals while they are still in training. Occasionally, more than one foal can be obtained from a single mare in a given year.

The success rate of embryo transfer is dependent upon many individual components. For example, age and fertility status of the donor mare and recipients, stallion semen quality, synchronization of both donor and recipients, and handling of the embryo after recovery. In general, the success rate of ET is good. Sub-fertile mares may require treatment before entering the program to maximize the success rate. Dr. Elizabeth Martinsen can evaluate your mare on an individual basis to give you a better prediction of results.

Embryo Transfer Technique

The donor and recipients are monitored daily at Bella Vista Equine Reproductive Services. The donor is bred as close as possible to ovulation to increase the chances of fertilization. Ovulation timing is also important in order to schedule the day and time for the embryo flush. This should occur 7 to 8 days after ovulation. During embryo recovery, several liters of a special solution are placed inside the donor’s uterus and the flush is recovered through a special cup containing an embryo filter. The filter allows separation of the embryo from the fluid recovered from the uterus. The cup containing a small amount of this special solution is transferred into a search dish. The dish is placed under the microscope and the embryo is searched.

Once the embryo is found and determined to be healthy, it is transferred to other dishes containing a special solution. The embryo is “washed out” of any debris. The embryo is manipulated carefully and placed inside a special embryo transfer pipette. The recipient mare is prepared and the vulvar area is cleaned for the procedure. The embryo is deposited into the recipient mare’s uterus. Most embryo transfers at Bella Vista Equine Reproductive Services are performed in this manner, without surgery.

Following the embryo transfer, the recipient receives oral progesterone to help her recognize that she is pregnant. The first pregnancy check occurs at 14 days (7 days after the embryo transfer, since the embryo was 7 days old at that time). The recipient is then checked at 25 days for a heart beat. Additional exams are performed at 30, 60 and 90 days to ensure that the pregnancy is progressing normally. The recipient mare can be released from Bella Vista after the 30 day pregnancy check.

Obtaining Recipients

We recommend at least two recipients per donor mare in case one of the recipients fails to have a normal cycle. Recipients can be provided by the donor mare owner. However, the recipients must undergo a breeding soundness exam to determine if they are suitable for the program. We encourage the use of young recipient mares or mares of known fertility.
Firethorn Equine Services has a limited number of mares for the embryo transfer program. The mare owner will have the option to lease or to purchase the recipient mare from Bella Vista Equine Reproductive Services. Please, contact us for more information about our recipient herd.

*Please consult our fee schedule by calling us.
*For questions please contact, Dr. Elizabeth Martinsen: (740)503-2004