Snake Bites in Cats

In general, nonvenomous and venomous snakes tend to have different physical characteristics. Nonvenomous snakes often have round pupils and a rounded head. Venomous snakes usually have elliptical pupils, not unlike a cat's. Their heads are often angled like a diamond or triangle. Most snakes in North America are not venomous. A bite from a nonvenomous snake can still be harmful to a cat, as snakes often carry infection-causing bacteria and a great number of parasites from feeding on dead animals. Snakes need warm weather to function as they are cold blooded. In colder climates, they hibernate during the winter and come out in late spring. Venomous snakes who have just woken from hibernation may carry greater volumes of toxins than at other times of the year. In warmer climates, snakes pose a threat year-round.

Snakes are reptiles that most cats consider as prey. A cat's natural instinct is to curiously investigate a snake, and even to pursue, hunt, and attack the animal. This can end poorly for the cat, as many snakes will bite when they feel threatened. Both venomous and nonvenomous snakes can bite. A venomous snake has the ability to inject powerful toxins into its victim's body that have the potential to be lethal. These include hemotoxins (affecting the blood), neurotoxins (affecting the central nervous system) and cytotoxins (affecting the cells of the body). A venomous bite from a snake can cause kidney failure, tissue death, adverse allergic reaction, and paralysis. Not every bite from a venomous snake involves a release of toxins.

The wound caused by a snake bite will vary greatly based on the type and size of the snake itself. Venomous snakes tend to leave two large puncture wounds in the flesh from their fangs. Nonvenomous snakes leave more of a horseshoe shape of smaller incisions. Not all bites are visible, especially in cats with long fur, and some bites do not puncture the skin. Symptoms may worsen as time passes. Signs to watch for include:

• Swelling
• Puncture wounds
• Bleeding
• Trembling 
• Vomiting
• Diarrhea 
• Weakness
• Ataxia (unbalanced gait)
• Tachypnea (rapid breathing)
• Cyanosis of the gums
• Ptosis (drooping eyelids)
• Dilated pupils 
• Hematuria (blood in urine)
• Paralysis 
• Coma

A cat who is allowed any outdoor exploration may at some point come in contact with a snake. If the snake feels threatened by the confrontation, a bite may follow. Possible causes are listed below.

• Venturing into areas with long grass
• Exposure to rural surroundings
• Hunting or chasing a snake

Unless you are an expert on snakes and you witnessed the bite take place, it is best to treat any snake bite as potentially venomous. Rush the cat to a veterinary clinic or animal hospital immediately so that life saving treatment can be administered. Call ahead to verify if the center you are going to carries antivenin on hand, and get a referral to somewhere that does if they do not. Keep the cat laying down and prevent movement. Try to position the bite area below the cat's heart. A pressure wrap, but not a tourniquet, may be used to slow the cat's circulation.

Once you have arrived at the hospital or clinic, be prepared to answer questions about the location and environment your cat may have been in when bitten. If you saw the snake, try to remember details about its appearance to help identify what type it was. Some centers in areas venomous snakes are known to inhabit may carry a snake venom test kit to further assist with snake identification. Full blood work will be needed, including a complete blood count and a biochemical profile. The time it takes for the cat's blood to clot may be measured. The vet may take note of fibrinogen (clotting protein) and platelet counts. 

Differentiation may be needed from other type of bites and wounds. Cultures may be performed to see if any bacterial infections are developing. A fecal exam may help confirm whether parasites are present. All of these tests and evaluations may be performed while the cat is already receiving supportive care.

In venomous snake bites, the goal of treatment will be to reverse the effects of the venom on the cat's body. In all snake bites the prevention and treatment of infection may be needed. 

Supportive Care 

Stabilization of the cat can greatly help its ability to survive a venomous bite. Hospitalization is required for this care, as intravenous fluids and feeding tubes may be required. Oxygen supplementation can assist in cases when the cat is having trouble breathing. 

Antivenin 

If it has been determined that the cat has been bitten by a venomous snake, the corresponding antivenin should be administered. It may take more than one vial to counteract the effects of the venom. Some cats develop allergic reactions to the antivenin.

Antibiotics 

As snake bites tend to be very unclean, antibiotics are often prescribed to rid the body of any harmful bacteria that may have been left by the snake. These prescriptions generally last from 1-4 weeks.

It takes most cats a minimum of one to two days to recover from a venomous snake bite with antivenin treatment. If immediate treatment has not been given, venomous bites are often fatal. Once discharged from the hospital, monitor the cat for any worsening in its condition. Keep the cat's activity lowered throughout the healing process. 

Administer all medications as prescribed by your veterinarian. The faster that treatment was received, the better chance the cat has of surviving a venomous snake bite. It may be best to keep cats indoors to prevent possible snake encounters. If you do allow your cat outdoors, do your best to eliminate things that attract snakes, such as piles of wood or long grass. Get to know what snakes live in your area and what they look like.