Secondary Poisoning: How Rodenticide Kills Dogs and Cats

Expert guidance from Southern California's chemical-free gopher control specialists.

909-599-4711 Book Service

Secondary poisoning — also called relay toxicosis — is one of the most tragic and preventable causes of pet death in California. It occurs when a dog or cat eats a rodent (or other animal) that was killed by rodenticide bait.

How Secondary Poisoning Works

When an anticoagulant rodenticide (like brodifacoum, diphacinone, or bromadiolone) is eaten by a gopher or ground squirrel, the poison accumulates in the rodent's body tissue. If a dog or cat then eats that rodent — or even parts of it — they ingest the accumulated rodenticide. Second-generation anticoagulants in particular concentrate to very high levels in rodent tissue, meaning even a small amount of poisoned prey can deliver a lethal dose to a pet.

Symptoms of Anticoagulant Poisoning in Pets

Anticoagulant poisoning prevents blood clotting. Symptoms typically appear 3–7 days after exposure and include:

If you suspect rodenticide poisoning, take your pet to an emergency veterinarian immediately. Do not wait for all symptoms to appear — by the time obvious bleeding occurs, internal damage may already be severe.

Which Animals Are Most at Risk

In Southern California, dogs are most commonly affected because they dig and explore areas where gopher control has been done. Outdoor cats who hunt are also at significant risk. Raptors like red-tailed hawks and barn owls are frequently killed by secondary poisoning from rodenticide-contaminated prey throughout the region.

Prevention

The only way to completely eliminate secondary poisoning risk is to not use rodenticide bait at all. Chemical-free mechanical trapping removes gophers without leaving any toxic residue in the environment or the gopher's body. Gopher Guys uses only mechanical traps for this reason.

Need chemical-free gopher control? 909-599-4711Book Online

Related Guides