Roaring Fork Equine Medical Center offers the following services for reproduction:

  • Mare breeding management with cooled or frozen artificial insemination
  • Ultrasound examination for pregnancy
  • Routine gestational health care

We do not offer any embryo transfer or stallion services at this time.

Is it possible to breed your horse?

In order to determine if it is possible to breed your horse, veterinarians need to know some additional information such as her history. How old is she? Has she had any foals in the past? If she has, has she had any issues with them? These questions help identify any red flags that could be an issue in getting her pregnant again. A thorough physical exam is performed to evaluate for any underlying conditions that might interfere with her ability to get pregnant or carry a foal to term. The reproductive tract is evaluated via a per rectum examination, where the cervix, uterus, and ovaries are palpated. Ultrasound can also be used to detect any abnormalities in these tissues. Advanced diagnostics, such as cytology (examining cells from the uterus and cervix under a microscope) and culturing for potential bacterial growth, can further assess the health of the reproductive tract. Biopsies may also be performed to identify any underlying tissue abnormalities that could interfere with her ability to get pregnant.

Dr. Kari Bevevino
Roaring Fork Equine Medical Center

How do you find a stud or stallion for your mare?

Finding a stud or stallion for your mare depends on your intentions with the foal. If you plan to register or paper the foal, you need to meet the requirements of the relevant association or registry. Check their websites or consult with them to ensure compliance. The internet and word of mouth are great resources for finding potential stallions. Local contacts may also have stallions available for breeding.

What is the process for breeding a horse?

There are several options for breeding a horse. One of the more hands-off methods is placing a mare in a pasture with a stallion and allowing her to accept the stallion during her heat cycle, known as live cover. Another option involves closely tracking the mare's cycle with the help of a veterinarian, using transrectal palpation and ultrasound to time ovulation accurately. Mares are seasonal breeders, typically cycling and ovulating in warmer months (spring, summer, early fall). In late fall and winter, mares are usually not cycling. If you plan to breed in early spring, it's advisable to have your veterinarian evaluate the mare's reproductive tract to determine if she is ready for seasonal cycling.

What are the different methods for breeding a mare?

The different methods for breeding a mare include:

  • Live Cover: The mare accepts the stallion or the stallion mounts the mare for live cover breeding.
  • Artificial Insemination: Semen is collected from the stallion and inseminated into the mare using a straw. This can be done with fresh, cooled, or frozen semen. Fresh semen is used immediately, cooled semen is shipped and used within 24-72 hours, and frozen semen requires more intensive management and precise timing.
  • Embryo Transfer: The mare is bred, and 7-8 days after ovulation, a uterine flush is performed to collect the embryo. The embryo can be frozen for future use or placed into a recipient or surrogate mare to carry to term.
  • ICSI (Intracytoplasmic Sperm Injection): An egg is harvested from the mare and injected with a single sperm under a microscope. The resulting embryo can be frozen, placed back into the mare, or placed into a surrogate mare.

What is the ideal age to breed your mare?

The ideal age to breed a mare is less than 10 years old. Beyond 10 years, a mare's fertility decreases, especially if she hasn't had a foal before. Mares that start foaling around three years of age and continue having one every year tend to remain fertile into their late teens and early 20s. While it is possible to breed older mares for the first time, it can be more challenging due to reduced fertility.

How long will your horse be pregnant?

The equine gestational length is around 340 days, which is nearly a year. There are many apps available that can help you calculate the foal's due date based on the mare's breeding or ovulation date.

How can you tell if your horse is pregnant?

Early pregnancy detection in mares can sometimes be achieved as early as 10 days using a transrectal ultrasound, though it may take until day 11 or 12 for the embryo to be detectable. Throughout the pregnancy, transrectal ultrasounds continue to be performed to monitor the pregnancy. As the foal grows and drops lower into the abdomen, a transabdominal ultrasound may be needed. Gender determination of the foal is possible but not precise, typically attempted between 54 to 80 days of pregnancy.

Are there any risk factors for your horse giving birth?

Horses generally do well with foaling, unlike cows. Mares usually regulate the size of the foal effectively, minimizing the risk of the foal being too large to birth. However, difficulties can still arise, and if a mare struggles with foaling, it is an emergency requiring immediate veterinary intervention. Prompt action increases the likelihood of successfully delivering a live foal. In some cases, a veterinarian may need to manipulate and remove the foal or perform a C-section.

If you have any other questions, please give us a call at (970) 987-4757. You can also email us at [email protected] and we will get back to you as soon as we are able. Don't forget to follow us on social media: Facebook and Instagram