I found this with google
What is Schnauzer comedone syndrome?
In Schnauzer comedone syndrome, dogs develop multiple comedones (blackheads) on the back and neck. These small skin bumps develop when a pore, the skin’s opening for each hair, becomes clogged with skin oils and debris.
Despite the name, Schnauzer comedone syndrome can occur in non-Schnauzer breeds such as Carin terriers and other rough-coated terriers. It is also called Schnauzer comedo syndrome, Schnauzer back, and Schnauzer back bumps.
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