Halitosis or bad breath in ferrets can be caused by several factors-- periodonatal diease, mouth ulcers adn the like ( bad teeth) or it can be caused by kidney / liver insufficiencies ( diseases) . I would have a ferret knowledgeable vet examione your ferret and do a blood panel to check kidney / liver function if no cause can be found orally--- just my thoughts Alicia I am *NOT* a vet-- visit our shelter page at: http://www.dartmouth.edu/~crassi/index.html [Posted in FML issue 2465]