Snake Bites can be Deadly
There are more than 25 different venomous snakes in Australia. The mere thought of encountering one makes me do a tiny vomit in my mouth. Almost. I should definitely consider moving to a nice, snake-free country like New Zealand. Throughout Australia, most (most than 75%) snake bites are from brown snakes, but here in Victoria tiger snakes account for around half.
Snake bites are common in our pets, because these creatures are often outside sharing the same space, and our four-legged friends usually can’t resist hunting or playing with things that move. Snake bites are usually seen during the warmer part of the year from September through to April, with most cases occurring over summer. The severity of symptoms and how quickly they occur depends on how many times a pet is bitten and where on their body they are bitten.
Unfortunately bites often occur on the face or in the mouth, because this is the body part that pets are usually poking at the snake. Right at this moment we have an adorable cat called Casper in the vet clinic, having sustained his second snake bite of the season! He’s pretty sore all over and has a particularly painful mouth. With some antivenom, intravenous fluids and tender loving care we expect him to make a full recovery. He gets a little grumpy with us now and again, but all it takes is a tummy rub and we’re best buddies again.
Why is Snake Venom Bad?
Australian venomous snakes are all part of one big slithery family called Elapidae. The venom from elapid snakes is devilishly complex, and does a number of horrible things. The main issues it causes are paralysis due to neurotoxins, muscle damage due to myotoxins, and bleeding tendencies due to coagulation system toxins.
Snakes can often be found around water sources or hiding in long grass. They also like to hide in places like piles of firewood or under sheets of corrugated iron. I vividly remember lifting a sheet of this on my grandparents’ farm as a child and the terrifying discovery of a young snake warming itself underneath. If you have areas with these sorts of things lying around it’s best to tidy up what you can and keep your dog away from what you can’t.
If you decide to do some summer bush walking or hiking with your dog, take extra special care near water and around long grass. Keep your dog on a leash rather than letting him run free, and stick to paths or tracks if possible. Snakes generally aren’t aggressive and don’t seek confrontation, so staying alert and keeping out of their way is the best way to prevent a bite. Most bites to humans occur when they are trying to capture or kill the snake.
Signs of Snake Bite in Pets
If your pet has been bitten by a snake you want to recognise the signs so you can get veterinary attention as soon as possible. The symptoms can vary depending on the species and age of the snake and where on its body the pet is bitten.
Generally brown snake envenomation causes paralysis and bleeding tendencies, while tiger snake bites cause muscle damage as well (which is why our friend Casper is feeling so miserable).
There are two main stages possible after a snakebite.
Stage 1: The Pre-Paralytic syndrome (Collapse and Vomiting)
Pets, especially dogs, may collapse and vomit soon after being bitten. Other signs we might see at this stage include salivation, trembling, and rapid breathing.
The pre-paralytic syndrome is vitally important.
Any animal that experiences this syndrome has received a lethal dose of venom.
Pets often appear to recover shortly after, so prompt treatment is not sought. If a dog or cat that has been bitten by a snake vomits and collapses, the worst is yet to come. It doesn’t matter if they seem fine.
Get to a veterinary clinic immediately.
Stage 2: Paralytic Signs (Dilated Pupils, Weakness, Paralysis and Death)
This is really unpleasant to read about, but being aware of the signs just might save your pet’s life.
- Around two to six hours after being bitten by a snake, a pets pupils will become large and unresponsive to light.
- They become weak in their hind legs which can make them stagger around and fall when walking. Over a short time this progresses to involve the front legs as well, and then worsens until the animal is paralysed.
- At this stage the pet will be lying on its side, unable to even lift its head. Breathing becomes more and more difficult.
- This leads very quickly to death.
What to do if Your Pet is Bitten by a Snake
Keep them as calm and quiet as possible and get straight to your vet. There is nothing you can do at home. If you are hiking or camping and are a long way from a veterinary clinic you can apply a pressure bandage over the bite site, but this really only has potential benefit if the bite is on a limb, and obviously isn’t an option for a pet that is bitten on the face.
A dog or cat that has received a bite from a venomous snake needs antivenom and intravenous fluids at a veterinary clinic. Reported survival rates in dogs range from 75 – 91% for those that receive antivenom, down to 31% if they don’t.
What NOT to do
While it may be helpful for a vet to know what type of snake was involved, please,
DO NOT TRY TO CAPTURE OR KILL THE SNAKE.
You won’t be able to help your pet from the back of an ambulance and if someone walks into the clinic with a wriggling snake in a paper bag I may just run away and never return. Snakes are really difficult to identify anyway, varying substantially in appearance within a single species. There are tiger snakes without stripes and brown snakes can vary in colour considerably, as illustrated by the two very different brown snakes below.
If you can see where your pet has been bitten, it’s best not to wash the bite site. Some vets may use this to obtain a sample for use in a venom detection kit.
Do not apply a tourniquet.
How Do Vets Treat Snakebite in Pets?
Antivenom vials contain enough antivenom to neutralize one average venom yield. What this means in practical terms is that the antivenom needed by an individual animal does NOT have anything to do with the size of the pet. It relates to the amount of venom injected during the bite and how many times the pet has been bitten.
Antivenom is really expensive. It’s produced by gradually making horses immune to the venom, collecting some of their blood, and harvesting the antibody-containing serum.
Affected dogs and cats need to behospitalised for administration of antivenom and intravenous fluid therapy. They need to be monitored carefully fordeterioration in their condition, signs implying a need for a second vial of antivenom, and signs of an allergic reaction to the antivenom itself. Some more severely affected patients may require oxygen therapy or even mechanical ventilation if they can’t breathe for themselves. They require constant monitoring and nursing care. For these reasons treatment for snake envenomation can cost thousands of dollars.
1. Be Prepared and Minimise Risk
- Before going for a bushwalk or hike try to find out if there are expected to be snakes in the area.
- Use your judgment based on the area and surroundings and keep your dog on lead if there is a risk.
- Don’t let your dog run around near water sources or in long grass
2. Know the Signs of Snakebite
You may not actually see your dog get bitten, but if there is vomiting and collapse, excessive salivation and trembling, or your dog becomes weak in the hindlegs, it should be considered an emergency until proven otherwise. Get to the nearest veterinary clinic as quickly as possible.
3. First Aid
Unfortunately there isn’t much that can be done prior to receiving veterinary care. Keep your dog as calm and quiet as possible and consider a compression bandage if appropriate.
This post is adapted from one I wrote in 2015 for the awesome Dog Adventures.
Have you ever encountered a wild snake?