Snakes

Article written in Spring 2011

Part 1: Ssssspring and ssssssummer are sssssnake ssssssseasons...

Yes it's that time of the year again. It's warming up, the sun has come out and so have the snakes. Just last week one of our patients, Jessie, had a nasty fright. Her owners were in the kitchen when they heard her yelp as if in pain. When they looked out of the window they saw a big Eastern Brown snake quickly slithering away. Fearing the worst they called us at Murwillumbah Vet Clinic and we told them to bring Jessie in to see us immediately.

Fortunately Jessie hadn't shown any of the signs of snake bite by the time she came in. These can include trembling, vomiting, collapse, and hypersensitivity. In order to be sure she hadn't been bitten we performed some blood tests, kept her in hospital under observation and repeated the tests 3 hrs later. All seemed well but, as snake bite signs can be delayed and some tests can give us false negatives, Jessie was sent home under strict instructions to observe her closely for at least the next 24hrs. Jessie was very lucky and probably received a dry bite in which no venom was transferred or just got a scare.

With Eastern Brown snake bites there is a wide variation in the time from being bitten to the onset of signs and all patients suspected of snake bite must be observed closely for a minimum of 24 hrs. Cats often initially show a weakness and wobbly legs (unfortunately very similar to tick paralysis) progressing to difficulty breathing, disorientation, drooling saliva, red urine and glazed eyes. In dogs, initial signs are often vomiting, drooling and collapse followed by an apparent recovery for half to twelve hours. From this point they will deteriorate quickly with similar signs to cats. The vast majority of dogs and cats will die without antivenom.

Any pet suspected of snake bite should be kept quiet and immobilised to delay the spread of the venom while you call your nearest vet for advice. A snake bite is a life-threatening emergency and treatment can be very expensive and involve your animal needing intensive care for days. Even with the most thorough treatment available we still lose pets to snake bite. Please consider pet insurance as often treatment will be covered by your policy.

Next month we will discuss a case of a bite from a Small Eyed Snake which is another snake commonly found in our area.

Part 2: Small-eyed snakes can cause a big problem

In our last newsletter we talked about Eastern Brown Snakes and their effects on our pets. Another very common snake in our area is the Small Eyed snake, which is often mistaken for a juvenile red-bellied black because of the similar colouring. This snake differs from Brown Snakes and Red Bellied Blacks in that it is more active at night. One of our patients, ‘Gizmo', was found to have killed what her owners thought was a red bellied black late on the night of the Melbourne Cup Races. They rushed her (and the dead snake) into the clinic and on further investigation it was indeed a Small Eyed Snake.

There is less understood about this snake's venom, but we do know it causes muscle breakdown, which leads to kidney failure as the breakdown products are excreted through the kidneys and urine. Initial signs can be mild to moderate swelling at the bite site, sometimes vomiting and diarrhoea, anxiety and drooling, followed by weakness, collapse, and red urine. We test for a positive bite by looking for a muscle breakdown enzyme in the blood and looking for muscle pigment in the urine. When we tested ‘Gizmo' she did indeed have these so we started her on high rate fluids to protect her kidneys. ‘Gizmo' stayed in hospital for a week and required regular testing of her kidney function for a month, so it was VERY lucky that she was fully insured!! There is no specific antivenom for this snake as it is not common all around Australia, though tiger snake antivenom is thought to be slightly helpful by some vets.

Any pet suspected of snake bite should be kept quiet and immobilised to delay the spread of the venom while you call your nearest vet for advice. Snakebite is a life-threatening emergency and treatment can be very expensive and involve your animal needing intensive care for days. Even with the most thorough treatment available we still lose pets to snake bite. Please consider pet insurance, as often treatment will be covered by your policy.