I'd be worried about ring worm - in dogs, it's not a ring - but it does sorta look like cradle cap. Marcel caught ring worm from his previous vet. To diagnose it, vet has to grow culture out for 10-14 days, and scope it. If positive, they usually do fluconazole x 6wks - then do another culture to assure it's gone. Did the vet do a scraping? At least then they'd know if it was bacterial. Let us know how it goes
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