My boyfriend and I recently adopted a 2 year old pit bull terrier mix from our local humane society (3 days ago), and he seems to be scratching more than normal since we've brought him home. This morning I also noticed that he was licking / chewing on his right rear foot and when I looked between the pads on his foot, the skin was red and irritated. Is his scratching / licking a symptom of an allergic reaction, or is his skin just dry and we can remedy it with a moisturizing shampoo?