My dog has these itchy spots popping up. They’re risen and have a scab over them. If you remove parts of the scab, there is a clear wet substance coming from the spot. Hair is also coming off with the scab. They are the size of a nickel, and I don’t see any other tiny spots or bumps around them. No change in diet/monthly preventatives. He has one on his back and one on his chest. He is a neopolitan mastiff if that matters. Trying to avoid a vet visit if possible.