An umbilical hernia in a foal can result from a number of causes.
It can be the result of trauma at birth, which may not have been apparent to any onlookers, or a hereditary defect. In the latter, most common cause, the hernia results purely and simply because the muscles around the navel failed to close at birth.
Whatever the cause, it manifests itself as a bulge where the umbilical cord was or is attached. The swelling is usually part of the peritoneum, a sac of tissue that envelops the internal organs. A hernia may also contain part of the intestine.
This series of pictures show the use of elastrator rings to treat an umbilical hernia, and its healing. The veterinarian who performed the procedure has viewed the images and was of the opinion that the amount of tissue reaction around the site of the hernia was worse than usual. The foal, however, showed no apparent signs of discomfort during its recovery and did not require further treatment.
Umbilical hernias are not considered immediately dangerous, but a vet should nevertheless be called to assess the risk to the foal.
The danger is that intestine pushing through the hole in the abdominal wall may strangulate. This means a section of intestine becomes trapped. Circulation can be affected, bleeding may result, and infection and inflammation may develop. If badly affected, the section of bowel can begin to die (necrosis) and the outcome is usually the death of the foal.
Most umbilical hernias are of what is known as a reducible type. That means, any bowel in them is still healthy and can easily be pushed back through the abdominal hole.
Your vet will decided the appropriate course of treatment once he has assessed the size and status of the hernia.
In minor cases, the veterinarian may recommend leaving the hernia in the expectation the abdominal wall will close over of its own accord and the problem will right itself. It is important, however, that the vet make this call, as a bad decision may cost the foal its life.
In more serious cases, where the intestine cannot be pushed back through, where the hole is very large, or the hernia has strangulated, the only course open to the vet is surgery. The procedure is likely to cost upwards of $NZ2000.
An increasingly common method of treatment involves the use of elastrator rings – the kind used to dock lamb tails and castrate ram lambs or bull calves. The procedure involves giving the foal a general anaesthetic and rolling it on its back.
The vet then pushes the abdominal contents back through the hole and pulls the skin tightly together over the hernia site and holds it with the rubber rings. Some vets use only a couple of rubber rings, while others opt for several.
This tightened area of skin will hopefully stop the abdominal contents from coming back through the hole while the muscles of the stomach wall grow and seal over.
The procedure is not without risks. The ringed-off clump of skin, deprived of a blood supply, dies and rots, then falls off. There is a danger of infection from the site affecting too much healthy skin, causing the wound site to burst open. Infection can also enter the abdomen, with potentially serious consequences.
A veterinarian recommending the procedure should explain the risks. The success rate from this procedure is nevertheless very good, and few would argue that floating a foal to an equine centre for abdominal surgery is not without its risks in any case.
The procedure is likely to cost between $NZ300 and $NZ400.
It is essentially a modern-day equivalent of a procedure once used in which clamps were placed on the skin after the hernia has been pushed back inside the abdomen.
The key to a successful outcome for any umbilical hernia is early assessment by a veterinarian, who can recommend the best course of action.
DISCLAIMER: Information in this report is of a general nature only and is not intended to replace the advice your veterinary surgeon.This article is copyright Horsetalk and may not be reproduced in any form.
First published in February, 2006