Many dogs can get black freckles on their tummies. Other dogs get these black patchy/spotty areas on tummy due to inflammation. If you're doing belly bands, inflammation would most definitely be possible due to the constant exposure to urine on his belly skin. I would try using some hydrocortisone cream there.
__________________ ~ A friend told me I was delusional. I nearly fell off my unicorn. ~ °¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie °¨¨¨°ºOº°¨¨¨° |