Cocker Spaniels betty turned black

Question
Hi,

My 9 year old cocker spaniel's belly turned black about 7 weeks ago. Recently, while grooming, I noticed the black is spreading and has turned one of his moles completely black. I thought it was the new treats I had bought him but I stopped feeding him those over a month ago and it's still spreading. I'm aware cocker's seem to be sensitive towards allergies but in this case I don't know what to do.  Do you have any idea of how we can nurse our precious dog back to health and have his belly/skin pink again? Also, our dog has a bad habit of licking his bumm all day which started about a year ago. Our vet says that is due to his anal gland being full but the behavior continues even after it's drained. any ideas about licking? Thank you for your help. Oh, by the way we feed him Nature's choice fish and potatoes mixed with Veggies(this seemed to agree with his stomach. All other foods would cause major gas for him) Not sure if this info is needed. Thanks. ~Mina~

Answer
IF this black stuff is pigmented skin, there is probably not much that can be done.

However, if the dog has skin allergies or is hypothyroid, then that can change back to pink as the disease is controlled.  Ask your vet to see if your dog has either of these conditions.