Novice Cat owners - Cat disease manifestations, as a veteran cat breeder, here are some of the most common cat disease manifestations. I measured them all, otherwise I wouldn't share them with you. You may have heard that when a cat is sick or old enough, it will run away from home, find a quiet place, and wait for its death quietly, without letting its owner see it. Therefore, since you have raised such a proud pet, you must carefully take care of it and actively treat it.