[107barney]

Originally Posted by ladyjane

Did the vet do any skin scrapings or blood work? His hair looks very dry. Could be thyroid..that often happens with hypothyroidism.

Hypothyroidism in Dogs: Symptoms and Treatment on MedicineNet

If your vet cannot diagnose it, I would suggest a vet dermatologist.

I agree with LadyJane. If your vet didn't scrape the skin to make a diagnosis, then a vet dermatologist surely can. You can find one here: https://www.acvd.org/locator/locator.asp