The Embryo flushing is a non-invasive procedure that, through an uterine flushing performed at 7-9 days after insemination, allows an embryo to be colllect from a mare (donor) and transferred to another mare (recipient), who will carry the pregnancy to term.
The advantages of the embryo transfer are several:
1.Increase the reproductive capacity of high-genetic-value mares;
2. .Allow to have offsprings from a mare that is still in competition and therefore not able to carry a pregnancy without stopping her competition career,
3. .Optimize the fertility of older mares with fertility or reproductive system problems.
4. Allow to have foals from mares that have reproductive or general problem and not able to carry the pregnancy.
5. A mare can produce no more than one foal per year; with this technique it is possible to produce multiple foals from the same mare in one breeding season allowing the use of different genetic combinations.
The success of an embryo collection after an embryo flushing depends by several factors:
-The age and fertility of the donor. In general we can say that we have the 60-80% of success in young and fertility mares, and 50-30% in older mares (over 15 years old) or subfertile mares.
-The fertility of the stallion and the use of fresh or frozen semen (the % are higher with a fresh semen).
- The quality of the recipient mare, and the recipient/donor synchronization.
- The quality of the embryo collected from the mare.
The 75% of the embryos transferred results pregnant at the 14-day checkup, and there is typically a 10% rate of pregnancy loss.