Although toads do not have a venom injection system, they are considered venomous animals. This secretion acts as a defense against predators of these animals that lack spines, nails, and sharp teeth. Dogs may be envenomed via the mouth by playing, biting, or eating parts of the toad. Venom is secreted into the dog s mouth and is absorbed by the mucosa or by skin injuries. Ingestion of dead, dehydrated, or desiccated toads may also cause envenoming.
Toad venom is mainly cardiotoxic and causes envenoming similar to digitalis.
There are several components in toad venom, which may be classified according to their toxicodynamics as basic compounds and steroid derivatives. The steroid derivatives include cholesterol, ergosterol, and g -sistosterol, with no toxic action. The bufodienolids and bufotoxins have a digitalis-like action. Clinical signs and symptoms Symptoms of toad envenoming occur immediately after contact with venom. They may be restricted to local irritation or cause systemic signs, which may lead to death.