A CBC is a complete blood count. It can clue you in to things like viral and bacterial infections, lymphoma, etc. It should be done on any animal going under anesthesia but especially an older animal. Yes you should be concerned about your ferrets teeth. Dry cat food is not enough to keep the plaque off. A vet. can look at your ferret's teeth and let you know if they need cleaning. [Posted in FML issue 0461]