Skin pigmentation change

Question
Hello, my 7 1/2 yrs male neutered Staffordshire Bull Terrier has recently had a mast cell tumour removed.  He has made a good recovery but it was a Grade 3 so we know he doesnt have too much longer with us but as I say he seems to be doing well.  His food has recently been changed, he is on Hill Science Plan N/D which is cancer specific.  I have noticed that his skin pigmentation has gone dark pretty much all over, obviously you cant notice it where the fur is but it has spread quickly.  Other than that nothing else of note except his wind is very smelly.  Sorry but thought I should add all details I could think of. I was wondering whether I needed to take him back to the vet because of the change of skin colour.

Answer
Yes this is something your vet needs to see and assess. It could be the medication that he is on if he is on any, or it could be a sign of something else.

I am sorry to hear about the grade 3 diagnosis. These things can be a real pain and have a sad outcome. I hope that he is with you for a long time.
The gassiness is probably from the change in diet. That should settle down with time.

Call your vet for a check up on that skin.