City or suburban dogs might never encounter a snake, but dogs that live in rural areas or are taken on hiking, hunting, or camping outings have a high possibility of coming across a snake at least once. Most of these encounters will be harmless, but because many dogs will try to attack the snake or even play with it, there's always a possibility of a bite.
If your dog is bitten by a snake, seek veterinary attention right away, even if you know that the snake was nonvenomous. At a minimum, snake bites are painful and can cause infection, but venomous snake bites can kill a dog within hours unless your dog is treated right away, which will usually involve a dose of antivenin.
Snake Bites And Dogs
Fatal snake bites are more common in dogs than in any other domestic animal. However, with prompt treatment, up to 80 percent of bitten dogs survive. Typically, dogs are bitten on the face, neck, or leg, but any part of the body might be bitten. As a general rule, snake bites on the body or face are more serious than bites to the legs, but all snake bites should be treated; a nonvenomous bite requires proper cleaning to prevent infection, while a bite from a venomous snake potentially requires treatment with antivenin.
Symptoms of a Snake Bite on Dogs
Many factors influence the types of symptoms your dog might experience after a snake bite, as well as the severity of those symptoms. The type of snake is the most important factor—a bite from a venomous snake is far more serious than a bite from a nonvenomous snake—but symptoms also depend on whether or not the snake injected venom (venomous snakes do not always release venom during a bite), how many bites were delivered, the size of your dog, and the part of the body that was bitten.
If your dog is bitten by a nonvenomous snake, or the snake does not deliver venom, common symptoms include swelling and bruising at the site of the bite. Usually, the bruise will spread quickly around the puncture wounds created by the snake's fangs, although this is not always easy to spot on dogs with long or thick fur. Depending on the type and size of the snake, you may or may not be able to see the actual punctures in the dog's skin.
However, if your dog is bitten by a venomous snake, the symptoms are likely to be far more severe. Symptoms your dog might display after a venomous bite include:
If a venomous snake bites your dog, dramatic symptoms may start within minutes. Your dog may begin to shake, or you might observe twitching muscles, especially in the dog's back legs. Often, the pupils of your dog's eyes will dilate wide, although this can be difficult to see in dogs with very dark eyes. The legs might become weak, causing your dog to fall to the ground. Most dogs will appear very agitated or nervous; you'll see your dog pant heavily, pace, drool, or even froth at the mouth. Many dogs will vomit, or your dog might develop diarrhea. It is crucial to get your dog to a veterinarian as quickly as possible if you observe any of these symptoms after an encounter with a snake.
While the majority of snakes are not venomous, and any snake might bite, a strike from a venomous snake is potentially far more serious for your dog. Venomous snakes endemic to the United States include copperheads, cottonmouths (water moccasins), rattlesnakes (pit vipers), and coral snakes. The four types have the following characteristics:
- Rattlesnakes usually are brown or reddish with darker diamond-shaped patterns on their back and rattles on the end of their tail. They can reach as much as 6 feet in length. In general, pit vipers have slit-eyed pupils like a cat (compared to round pupils in non-poisonous snakes), pits beneath their eyes, big arrow-shaped heads, rough scales, and a pair of fangs in the upper jaw.
- Water moccasins hang out near streams or in swamps. They reach 4 to 6 feet in length and are dark brown to black, with faint bands that can be hard to distinguish. The inside of the mouth is white, giving the snake its "cottonmouth" nickname.
- Copperheads can be reddish to golden tan and have darker hourglass-shaped bands along their body. They reach about 2 to 3 feet in length and are typically found around leaf litter and woodpiles.
- The coral snake can be recognized by its small black-nosed head and vivid stripes of red, yellow, and black. Red and yellow bands are always next to each other. Coral snakes can be distinguished from king snakes (same bands of color but in a different order) by remembering this rhyme: “Red next to yellow kills a fellow.”
If you can spot the snake that bit your dog, that information will be helpful to the vet and may help dictate the treatment plan.
Diagnosing Snake Bites on Dogs
Often, you'll actually see your dog being bitten by a snake. If you aren't sure of the type of snake, be prepared to give a clear description to the veterinarian, or take a photo if possible, but do NOT attempt to catch or kill the snake, which could lead to you yourself being bitten.
If you don't witness your dog being bitten by a snake, but the dog displays symptoms of snake bite, or has any obvious bite wounds, assume the dog was bitten and head to your vet's office. The veterinarian will make the diagnosis based on your account, a physical examination of your dog, and any symptoms your dog is experiencing.
If you know or suspect your dog has been bitten by a venomous snake, get to an emergency veterinary hospital immediately and follow these steps en-route:
- The poison can cause shock, paralysis, or make the nostrils or windpipe swell shut. Remove the dog's collar or harness so that if its body swells, the airways remain unrestricted. Be prepared to give your dog rescue breathing.
- Keep your dog as quiet as possible on the way to the vet. Any movement can speed up the poison’s spread through the blood circulation. Try and keep the area that was bitten below the level of your dog's heart.
- Turn up the AC in the car to help slow down circulation. Apply an ice pack directly to the wound; even a package of frozen vegetables will work. Keep the ice on until you reach the vet's office.
- If you can see bite marks, rinse the wounds with water or a baby wipe to get the venom off the dog's body.
Once you arrive at the vet's office, they will examine your dog and likely treat it with antivenin, which is a commercially made serum that neutralizes the effects of the snake venom. Some antivenin is specific to the type of snake that bit the dog, so the more information you have, the better the vet will be able to treat your dog.
Even if you are positive that your dog's bite was delivered by a nonvenomous snake, a visit to the veterinarian is still in order so the wound can be cleaned and antibiotics prescribed to prevent infection.
Prognosis for Dogs With Snake Bites
With prompt treatment, your dog is very likely to survive a snake bite, even if the snake was venomous. However, the first two hours after a bite from a venomous snake are critical; if treatment is delayed beyond this point, the dog may succumb to the injury.
With treatment, your dog generally will start to rebound within 24 hours. If not, the prognosis is poor. As a general rule, bites to the dog's abdomen or chest are the likeliest to prove fatal. And even a nonvenomous bite can become very serious if infection sets in, which is why all snake bites should be treated by a veterinarian as soon as possible.
How to Prevent Snake Bites
There is no absolute way to prevent snake bites in dogs. The best method is to supervise your dog, especially in areas where snakes are present. Clear away brush from your yard, and keep your dog close by while hiking or camping. It’s always easier to avoid and prevent tragedy than to deal with the aftermath.
Snakebite. Merck Veterinary Manual.
How to Treat Your Dog for Snakebites. Veterinary Specialists of the Rockies.
Hunter T, Ernest Ward. Snakebite Envenomization. VCA Animal Hospitals.
Types of Venomous Snakes. Centers for Disease Control and Prevention (CDC).