Snake venom and horses
by Lyndi Gilliam, DVM, MS, Ph.D., DACVIM
Standing in the pasture or riding on the trail, horses are susceptible to snake bites. Snake venom can vary by species and many factors affect the severity of the bite.
Snake venom often contains substances that affect the overall health of your horse. Specifically, snake venom can cause digestion and the breakdown of tissues and blood vessels. It can also impair blood clotting or damage the heart. Some may even contain neurotoxins.
Common locations for snake bites in horses are the lower legs and the muzzle. Factors that influence the severity of the bite include:
– Snake species
– Size of the snake
– Age of the snake
– Recent feeding history of the snake
– Number of bites received
– Time of year
The severity of the bite can be related to the size and age of the horse as well as the location of the bite. In addition, any concurrent medical conditions the horse has and any drugs the horse is receiving may weigh in on how severe the bite is to the horse’s overall health.
So how do you know if your horse has been bitten by a snake?
Signs may occur within minutes or be delayed for hours. It can vary depending on the snake species, the dose of venom received, the location of the bite and other factors. You may see paired puncture wounds with a small amount of blood. If the bite occurs on the face, there may be painful, rapid swelling of the nose.
Horses are obligate nasal breathers – they cannot breathe through their mouth. If the nasal passages swell significantly, the horse may suffocate. Bites on the muzzle constitute a veterinary medical emergency.
If your horse’s nose starts to swell, lubricate a short section of garden hose and pass it into the nostril. This will keep the airway open while you wait for veterinary attention.
There are several treatment options for snake bites. These include administration of anti-venom. A tracheostomy may be placed for horses having trouble breathing. Some horses may require fluids given in the vein to treat shock. Frequently horses are administered anti-inflammatory and pain medications. Horses may also receive tetanus protection and antibiotics.
A mare named Barbie was treated for a snake bite by veterinarians at Oklahoma State University’s Veterinary Medical Hospital using an unconventional method. The daughter of a three-time world champion roping horse received three maggot therapy treatments and survived. Nearly 10-years later, her owners report she is a big, strong and healthy horse.
Snake venom can remain in the horse longer than one might think and it can damage the heart muscle. This damage may or may not be permanent. A recheck by your veterinarian can determine if permanent damage has occurred and when the horse is safe to ride again.
Do not attempt to suck out the venom, use a tourniquet or use ice or heat at the snake bite site. Contact your veterinarian immediately and follow their instructions for the safety of your horse.