KALIYAT asks: "My Sheltie has a round sore that looks like a blister on the underside of his ear. It's itchy and the skin is warm around it like it's infected. There is also some scaly skin around it too. It's been there for a couple weeks and doesn't seem to get any better. It's not a tick, the inside is liquid like a blood blister. I've used an anti-biotic cream on it but it hasn't gone away yet. Does anyone have any experience with something like this?"