If it's a significant weight loss, he should see the vet. If he's a hunter and eats his prey, that's even more reason as, if he ingests a mouse or other rodent that's eaten poison, it can also poison him. Is he neutered? Hopefully so. If you suspect that your cat is not well, your best bet is to take him to his vet. A cat's weight should remain fairly consistent. It's possible he is more active in the spring and this causes him to lose weight, but it's always a good idea to keep an outside cat vaccinated and vetted for his protection.

Izadore (Izzie) answered on 6/6/11. Helpful? / 0