I have three cats and have had one of them for a few years, which I adopted from the outside. He was dewormed and neutered and given a flea/tick bath and everything! Well, since then, nearly every day that I have had him he has thrown up at least once per day. It is SO annoying because he'll do it on my couch, carpet, stairway, etc. I know it is because he eats too fast, it was a survival instinct from the wild. He likes to eat his throw up, too. How do I prevent him from eating so fast?