Decon is absolutely harmful to dogs. Decon contains warfarin which is a blood thinner. This poison will cause bleeding. If you believe that your dog has ingested the poison you should get it to the vet as soon as possible. The vet will treat the dog with vitamin K to help stop the bleeding.
Depends.... Warfarin (Decon, Pindone) Warfarin is incorporated into grain feeds for use as a rat and mouse poison. In dogs, a toxic dose is one half teaspoonful per pound body weight. In these amounts can be quite harmful to the dog.