i have two cats as well as ferrets. the cats roam... the ferrets don't. i don't have any problems with my ball and them as long as i haven't handled the cats or ferrets prior to handling my snake.. same as with mice... wash their scent off of your hands. usually if im going to handle my snake, i make sure i havent touched the other animals.. i even sometimes put on a fresh t-shirt if the cats have been on me.. the cats dont usually see the snake at all. if the snake is out i make sure the cats are locked in another room with food, water and litterbox. hope that helps ya.