I had noticed that Basil (ferret) had a weird orangish patch between his shoulders and a little less fur on his tail, so he went to the vet for a checkup. Vet said that the discoloring is just on his fur, and is probably from his fur changing for the seasons. Same with the tail. He was all healthy (except we should try to brush his teeth, but it's not a big deal if we don't) and I'm reeeeeeaaaally happy We're just going to keep an eye on the tail fur and fur on his sides to make sure he's not getting adrenal disease.