Need suggestions. Background: My daughter has a terrier that was found stray several years ago. We don't know his age but suspect he is quite old now. He has always had chronic ear infections but they don't seem to hurt him. He is pretty much deaf now. He is on antibiotics for them quite often. He has also had chronic diarrhea for a long time. He was 19# when found and has been losing weight little by little and is now about 15#. His ribs are sticking out like he's starving yet he eats a lot. She has changed food a number of times, always using a single protein kibble. The diarrhea is really stinky. Sometimes he eats it if he has an accident when she is not home. Flagyl doesn't seem to help. He has had excellent vet care. Last week they finally tested him for EPI - negative. Has no giardia or any type of parasites. Bloodwork is excellent. Does anyone have any ideas?