A study in the Journal of Comparative Biochemistry and Physiology compared the effects of snake venoms on the blood-clotting factors in dogs and cats. The researchers found that 31 percent of dogs survive a bite by an eastern brown snake without receiving antivenom, while 66 percent of cats survive. With some snakes, death is caused by “venom-induced consumptive coagulopathy,” a condition in which the venom causes a massive clotting response, resulting in consumption of clotting factors and resultant inability to form blood colts.
The researchers used a coagulation analyser to test the effects of 11 venoms on dog and cat plasma in the lab. They found the spontaneous clotting time of the blood—even without venom—was dramatically faster in dogs than in cats. This is consistent with clinical records, which show a more rapid onset of symptoms in dogs.
Cats have other advantages. Dogs are more likely to be bit around the head, which is a very vascular area, so venom moves quickly throughout the body. Most dogs are also more active after a bite, often attacking the snake. Cats are more cautions, perhaps tapping a snake with a paw. With their quick reflexes, cats can avoid many bites and, if they do get bitten, it is usually out on a limb. In addition, they are more likely to hunker down and be still after a bite, so the venom does not travel as fast through their bodies.n
Zdenek,C.N., et al. Pets in peril: The relative susceptibility of cats and dogs to procoagulant snake venoms. Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2020; 108769 DOI: 10.1016/j.cbpc.2020.108769.