Deuce has these little red bumps on his chin that sometimes pop and bleed. He is also loosing the hair on his chin and its looking very red and irritated. He has some bumps on his muzzle around his nose and mouth that look white, but would probably be red if his muzzle wasn't black. Is there anyway to tell if this is acne versus an allergic rash? We are going through the process of elimination to determine if he has a food allergy. He started to show allergies when we switched from Iams to Canidae so we have been on Natural Balance Potato and Duck for two weeks and no improvement on the chin/muzzle area. I took away his plastic water dish tonight and put out a stainless steel one instead. Any ideas would be appreciated. I hate to see his handsome face with these little bumps, I miss his cute little white chin.