BREDA-LAKE VIEW VETERINARY SERVICES
1181 9 TH STREET
BOX 905
LAKE VIEW, IA 51450
(712) 657-8553
(712) 657-2245 (FAX)
EQUINE EMBRYO TRANSFER
Equine Embryo Transfer is a process where a fertilized embryo is removed from a mare’s uterus (this mare is called a donor mare) by a sterile flush (a sterile catheter is placed into the mare’s uterus, a sterile solution is flushed into the uterus and back out into a sterile filter cup to trap the embryo). This collected embryo is then transferred into a different mare (this mare is called a recipient mare) directly into her uterus with a sterile pipette.
A Donor Mare is a mare that has been chosen to become pregnant but to not carry the foal to term.
A Recipient Mare is a mare that has been chosen to receive the embryo from a pregnant donor mare, to carry the foal to term as well as nurse and raise the foal to weaning. A recipient mare may be a normal reproductively healthy mare (a mare that cannot carry their own foal or is reproductively compromised for any other reason is not a good candidate. The recipient mare needs to be a normal reproductively healthy mare that has ovulated her own follicle within a short time of the donor mare. This mare must be ultrasounded daily to determine the exact ovulation time.
The donor mare as well as the 3 possible recipient mares estrus cycles are synchronized using hormones. All mares are ultrasounded daily through the heat cycle to determine exactly when the donor mare ovulates to match ovulation of the closest recipient mare.
On day 7-8 post ovulation the donor mare is flushed and IF an embryo is recovered it is transferred to the recipient mare.
The donor mare can go home after the flush; the recipient mare stays at the clinic for approximately 7 days. She will be given Regu-mate therapy until approximately 7 days post transfer when she will be ultrasounded to determine if the embryo transfer is a success (the embryo is approximately 14 days old at this time). If the transfer is a success the recipient mare can go home on Regu-mate therapy as described above. Repeat ultrasounds at 21, 30, and 45 days are recommended.
EQUINE EMBRYO TRANSFER PROCEDURE:
The donor mare is bred as normal. She is ultrasounded to determine the exact time of ovulation. We then flush the mare’s uterus with up to 6 liters of a special solution searching for the 7-8 day old embryo. Upon collection of the embryo the donor mare’s uterus is flushed with 1 - 4 liters of sterile saline with antibiotics to aid in the health of her uterus. Oxytocin and Lutalyse are used to expel any remaining contents from the uterus and to bring her back into heat.
Once we have collected an embryo from the donor mare, this embryo is maintained in a special solution until the recipient mare is prepared at which time the embryo is transferred into her uterus. The normal recipient mare must be given Regu-mate for the first 30 days of pregnancy in most cases. Blood tests will need to be done to determine progesterone/estrogen levels.
Success rates – in young healthy mares less than 15 years old usually run a 60-80% recovery rate per flush. Older/problem mares generally run about 30-40% recovery rates per flush. Once a good embryo is recovered, success rates generally run about 75% to 30 days pregnancy. An additional 5-10% of pregnancies may be lost after 30 days.
**We will do EVERYTHING in our power to make the collection and transfer a success. However, there are no guarantees. This is not a natural process and sometimes the recipient does not accept the embryo.