Today we are going to discuss equine embryo transfer.  Embryo transfer has become fairly common in the horse business due to the increasing success of the procedure.  One of the advantages of embryo transfer is that you can get several foals every year from just one mare by breeding her several times, removing the embryos, and transferring them to other mares called recipients.  These recipient mares will have their estrus cycles synchronized within a few days of the donor mare so the embryo is transferred from one uterus to the other at the same stage of cycling.  This synchronizing of estrus cycles is done with drugs and response is monitored with ultrasound. 

The donor mares are usually bred artificially.  Seven to 8 days after breeding, large volumes of solution are use to flush the embryo out of the donor mare’s uterus.  The embryo is trapped in a filter, microscopically identified, and carefully placed in the uterus of a recipient mare that will carry the foal to term.  In recent years, a new hormone product has become available that can cause mares to have multiple ovulations and multiple pregnancies.  In this case, multiple embryos can be flushed from a single mare in one cycle.  Embryo transfer is useful for owners that would like to get a pregnancy from a performance mare but not take her out of competition.  Also, even mares that are too young to carry a pregnancy can donate an embryo and have a foal.  Mares that have a damaged uterus can donate an embryo even though they may not be able to carry a pregnancy to term.  If you have a mare that you would like to get a foal out of but have been unable to get pregnant, contact your vet about embryo transfer, or contact us at tfbradio.com.