Botulism in dogs is a rare, but serious disease. It is caused by a very potent toxin produced by bacteria called Clostridium botulinum and it usually occurs after the dog ingests contaminated food or feeds on carcasses of infected animals. Symptoms include weakness, difficulty eating and breathing, vomiting, refusal to drink, papillary dilatation, and muscle paralysis.
There are seven different types of Clostridium botulinum: A, B, C, D, E, F, and G. Types A, B, E and F usually affect humans. Type C causes the disease in domesticated animals, including DOGS, birds, and horses, but it also has been reported in wild birds, like waterfowl. C. botulinum type D often affects cattle. There haven't been enough reports on the type G of C. botulinum, but it can potentially affect humans as well as animals.
The bacteria is present widely in nature, especially in soils and aquatic sediments, but it grows only in warm (40 to 120 degrees F), low-acid, oxygen-free environment. Otherwise, it produces spores that can stay dormant for years. Once the conditions are more favorable, the spores become active, germinate and produce the botulism toxin.
There are two forms of botulism in dogs: food-borne and toxicoinfectious.
The food-borne botulism occurs when the dog ingests either active bacteria or spores (which, then, become active and produce toxins) with food. Most incidents result from the dog consuming the carcass of a dead animal, but feeding the dog improperly handled raw meat or fish may also cause botulism. Canning process does not kill C. botulinum and from time to time canned dog food is recalled from the market due to contamination.
The toxicoifectious form of botulism in canines is similar to the wound and intestinal forms of the disease in humans. The bacteria may grow in improperly cared for wounds, in dead tissues of the liver or digestive tract (which may be caused by other gastrointestinal problems), and even in the lungs.
Dogs are relatively resistant to the toxin and botulism in dogs is rare. Unfortunately, because of this rarity, the disease may be easily misdiagnosed especially that its symptoms are similar to other problems, like poison ingestion, drug reaction, or stroke. It is important, then, for the dog owner to keep an eye on the dog to make sure it stays away from dead animals and other decaying food. Also, if the signs of botulism are present (the symptoms can be noticed within 12 to 36 hours of infection), the dog should be taken to the vet as soon as possible to ensure fast recovery. In most cases it takes about two weeks for a dog to fully recover, but botulism can be fatal if not caught early enough.