My dog is a Pitbull and Akita mix and is 5 years old.He has these sores that are like scabs that he keeps getting. They get bigger and they bleed when he scracthes them. Eventually they go away and new ones appear. I apply Hydrocortisone spray for dogs which is suppose to relieve the itching and promote the healing of flea bites, rashes & skin inflammation. But it doesn't stop them from reappearing. At one time he had a line of them that developed on his side. Once they go away, his fur is missing from that spot until it grows back in. When he had fleas in the summer time I thought they could have been from the fleas, but I checked him and he does not have any fleas at this time and he is still getting these sores. I would like to know what they are and what can I get to treat them? Thank You.