Blowfish / Pufferfish Toxicity

Perth's coastal lifestyle allows access to multiple pristine beaches and popular fishing spots where owners can enjoy the sea in the company of their beloved pets. Though the ocean presents a wonderful opportunity to exercise an relax in the fresh air, it must be remembered that that other animals have lived in these same seas for thousands of years, and in the process, have developed multiple ways to defend themselves against would-be predators. Many creatures possess spines, scales, teeth and toxins amongst their armaments, and blow fish and puffer fish are no exception.

Blow Fish and Pufferfish are members of the group Tetradontidae, which contains more then 120 species of highly toxic marine (salt water) fish. In addition to "puffing up" in an effort to trick predators into thinking they are bigger then they are, and to show off the spines some species possess, this group also produces a potent neurotoxin called Tetradotoxin, which affects the nerves in animals who choose to eat these fish. In some Asian countries, certain species are eaten by humans, but only after carefully trained chefs remove the internal organs which contain the most toxin - though even with careful preparation, this practice still caries a risk of "accidental" death.

Signs of Toxicity

Dogs often ingest blowfish or pufferfish on a casual basis while roaming along the sea shore or riverbanks and around jetties. Occasionally they are fed to the dogs by accident by well - meaning pet owners or fishermen. These fish are toxic both alive and dead, and even eating a portion of the fish can lead to poisoning. As your dog may not be witnessed eating these fish, it is important to be on the lookout for the signs of toxicity any time your pet has had access to the sea side. Dogs will often appear unwell after ingesting the fish, licking their lips and panting. They then may display nausea (drooling) and vomiting, and start to show signs of weakness, usually starting in the legs and continuing towards the head. This weakness eventually leads to an inability to control swallowing and eventually impairs the dog's ability to breath, resulting in death by asphyxia (respiratory failure). Treatment for this poisoning is possible, but success is more likely in pets receiving prompt and aggressive treatment by their veterinarian.

Treatment

Unfortunately, there is no specific "antidote" for blowfish/ pufferfish toxicity. After admission to hospital, initial treatment is aimed at removing as much unabsorbed toxin from the affected dog's gastrointestinal tract. Procedures, such as emesis (inducing vomiting) gastric lavage ("pumping the stomach") and enemas may be used to remove undigested fragments of fish. Activated charcoal may then be infused into the stomach to absorb dissolved toxin. Some of these procedures may be carried out under a general anesthetic if the pet requires help in breathing and to prevent aspiration (inhalation of vomit or fluids into the lungs).

Supportive care may include an intravenous fluid drip to rehydrate the pet and maintain normal blood pressure. Special fluids, such as Intralipid (a soluble fat solution) may be used to dissolve toxin in the bloodstream and decrease the amount of toxin affecting nerves. Pets which have lost the ability to breath may need be admitted to an intensive care facility to have their breathing maintained by a ventilator (a machine used to mechanically inflate and deflate the lungs via a tube in the throat). The longer a dog has been in this weakened state, the more likelihood it has of acquiring severe complications, such as pneumonia, brain and organ injury. The more severe and longstanding the signs, the lower the chances of a full recover, so prompt treatment is essential if blowfish/ pufferfish toxicity is suspected.

Prevention

Care must be taken when pets may be exposed to salt and brackish water areas where these fish exist. Keeping your pet on a lead allows the owner control over the pet's travels. Owners should also keep an eye out for any fish or fish parts on the beach or on fishing piers and be wary of any fish offered to pets. Though dogs are over represented in these toxicities, it is important to remember that cats and other carnivorous pets can also be affected if these fish are ingested.If you notice your dog your dog “eating” something on the beach or riverbank, you should ALWAYS assume it is a blowfish unless proven otherwise. A quick trip to the vet, for an early vomit, is always preferrable to the latter more protracted cases of poisoning, and also carries a much brighter prognosis.