Can A Dogs Anus Turn Black My Dog Is Bleeding From The Anus?

My dog is bleeding from the anus? - can a dogs anus turn black

smiles, and there was a question, but nobody gives a correct answer. I want to know why the vet could not do or say much more. I do not know where. I think you have cancer, why else would he every time I bleed a saddle? someone please help me, who with us for 7 years and a pit bull is very good and very sweet. Please help me ...