Does anybody know how to help my cat Domino lose weight? He's an American Shorthair who weighs 15-22 pounds. I have a bag of treats that I used to spoil him with but I don't really do it so often anymore. I've also not been giving him as much food and he's still fat. I've also have tried to give a little more exercise when I'm not busy. What else should I do to help him lose weight?