My dogs skin is turning black, starting on her belly, She is a 3 yr old, basset/chow mix and this has never happened before. I have scrubbed and it wont come off. It is the skin and not dirt. It is getting darker and covering more area over time. I don't know if this is significant but she was sprayed by a skunk about 1 1/2 months ago, i used a concoction off the internet to bath her in when it happened: peroxide, baking soda, and dawn dish soap. She also has a musty smell that wont go away maybe a little still lingering from the skunk but i wonder if it has to do w/ the skin problem.
Age: 3; Female; Breed: basset/chow mix
Often the darkening of abdominal skin is due to a problem with the thyroid hormone being too low. Along with that can come a yeast infection of the skin leading to the odor you are smelling. You can read about thyroid issues in dogs here
I'd suggest having your vet check her over to see if the problem is her thyroid. A blood test will show if that is it and there are meds that can help with that.
Another possibility is an adrenal gland problem causing Cushings disease but a thyroid issue is fairly common and your vet will likely check for that first.
Hope this helps you!
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics