Equine Abortions

If you have pregnant mares, you should be vaccinating them with a vaccine that prevents abortion from Equine Herpesvirus. In mares, abortion is a failure of the fetus before it reaches the 300-day gestation period. Anything after that period is considered to be an early delivery of the foal. There are many reasons that abortions occur. They can occur because of bacterial, fungal, or viral infections, insufficient nutrition, deformities, twinning, twisted umbilical cords, disease, hormonal problems, or even stress. Only around 40% of equine abortions are actually diagnosed as to the exact cause. The picture below is a fetus that was aborted because of stress and trauma. The mare was moved into a pasture with a dominant mare a few months before she was due. The dominant mare kicked her in the side and not long after, she aborted the fetus.

A lot of time and money are spent on the care of pregnant mares, so it’s important to protect your investment by spending a few dollars on a vaccine, giving proper nutrition to the mare, and trying not to put her in stressful situations. The vaccine will prevent abortions from Equine Herpesvirus. There are many different types of vaccines that prevent abortion from Herpesvirus, please see the article below written by Mike Yoder posted on October 3^rd for names and times given. Most breeding contracts require mare owners to vaccinate pregnant mares.

You may not always find an aborted fetus in the pasture or stall, particularly with early term abortions. Other signs of abortion include: coughing, fever, depression, discharge, mammary gland growth, bleeding, and swelling in the legs. A mare, however, may not show any signs.

Many people ride pregnant mares, but you have to be very careful when doing this because you don’t want to cause any stress to the mare. You will need to refrain from strenuous activity and always check with your veterinarian about when it is safe to ride her. Mares do need some exercise to remain healthy during pregnancy. If they do not exercise and are too fat, they may have problems delivering a healthy foal.

Hopefully, everything will go right with the pregnancy after all of your preparations and you will get a healthy foal like the one below.