Walnuts can be toxic to dogs. They may cause stomach upset, vomiting, diarrhea, and severe abdominal pain. In some cases, walnuts can trigger seizures and neurological problems. Moldy walnuts are especially dangerous because the mold may produce neurotoxins that are harmful even in small amounts. Even fresh-looking walnuts should not be given to dogs.
Walnuts for cats
Walnuts are equally dangerous for cats. They are hard to digest and may cause nausea, diarrhea, lethargy, and weakness. Their high fat content puts extra stress on the liver and pancreas. If a cat eats a moldy walnut, the risk of poisoning increases significantly.
If your pet eats walnuts and shows vomiting, diarrhea, seizures, or lethargy, seek veterinary help immediately.