A hernia is the displacement of an organ or tissue through a hole in the body wall that contains it. The body wall may be compromised because it is weak and/or is breached due to physical stress.

Umbilical hernias are the most common congenital (hereditary) disorder in the horse. It is a failure of normal development of the body wall at the umbilicus. The result is a defect that can be felt in the body wall, as a balloon or sac of abdominal lining that typically hangs down from the hernia. Umbilical hernias can also result from the foaling process.

Small hernias are common in foals and most of them slowly close over 6-24 months. This can be helped by gently pushing the hernia sack up with your fingers on a daily basis. However, larger hernias, defects in body wall larger than three fingertips wide, may need to be treated surgically. In larger hernias, there is also the risk of intestine becoming trapped in the hernia, a life threatening problem that may require emergency abdominal (colic) surgery.

For this reason, discuss whether or not surgery should be performed to repair the hernia, and when with your vet. There are several potential methods of treatment. The only well-accepted treatment is surgical closure of the hernia ring under general anesthesia.