Using a recipient mare has become a fundamental part of high-level equine breeding programs, whether through traditional embryo transfer or implantation following ICSI (Intracytoplasmic Sperm Injection). This technique allows a donor mare, often still competing or unable to carry a pregnancy, to pass on her elite genetics without having to gestate the foal herself.

However, the success of the process depends heavily on the selection and management of the recipient mare. She is far more than a passive host. Her health, temperament, veterinary care, and daily environment directly influence the outcome of the pregnancy and the health of the foal.

Key criteria for selecting a good recipient mare

A suitable recipient mare must be in excellent physical condition. This means undergoing a thorough veterinary exam, including a full reproductive assessment, disease screening (free from contagious equine metritis, negative Coggins test, up-to-date vaccinations), and maintaining a healthy body condition. Ideally, she should be between 4 and 12 years old, with a history of at least one successful, uncomplicated pregnancy.

Hormonal synchronization with the donor mare is also essential. The embryo transfer can only succeed if the reproductive cycles of both mares are aligned, with ovulation occurring within a very narrow timeframe. This is why specialized breeding centers often track multiple recipient mares to ensure one is hormonally ready when the donor’s embryo is available.

Temperament matters too. A calm, well-handled mare with a gentle disposition is far more likely to carry the pregnancy smoothly and demonstrate proper maternal behavior after foaling. On the other hand, anxious or aggressive mares may jeopardize both the foal’s safety and postnatal care.

The importance of proper care and welfare

Choosing the right recipient mare is only part of the equation—caring for her properly is equally important. As a living, sentient animal, she deserves the same attention and respect as any other horse in the breeding program. This includes proper nutrition, regular veterinary checkups, a stress-free environment, and comfortable, secure housing.

Beyond ethical responsibility, these welfare measures have a direct impact on pregnancy success. A healthy, well-managed mare is far more likely to carry the foal to term and give birth without complications. In contrast, poor nutrition, chronic stress, or undiagnosed infections can all increase the risk of miscarriage or foaling issues.

Insurance: A smart way to protect the pregnancy

Given the financial and emotional investment involved in embryo transfer, it’s strongly recommended to take out pregnancy loss and foal mortality insurance. This type of coverage typically applies from day 45 of gestation through to a live foal surviving the first 48 hours after birth.

To activate this insurance, the recipient mare must undergo a veterinary exam and be issued a pregnancy certificate confirming that the pregnancy is progressing normally. In the unfortunate event of loss, a veterinary death certificate ara required to file a claim. This insurance provides peace of mind and also promotes better oversight throughout the gestation.

To conclude

Embryo transfer success doesn’t rely solely on elite genetics or precise techniques. A large part of the outcome depends on the recipient mare’s health, behavior, and the care she receives. Choosing her wisely, treating her well, and providing consistent follow-up throughout the pregnancy aren’t just best practices—they’re essential.

A well-chosen, well-cared-for recipient mare offers the best chance of delivering a healthy, strong foal. By putting her welfare at the center of the breeding process, breeders aren’t just protecting an investment—they’re upholding the values of responsible and sustainable equine reproduction.