One thing to take into consideration: DO start the old age exams and tests earlier than for others with any neural crest variant ferrets. One repeated topic of conversation on the FML and in Ferret-Genetics in Yahoogroups has been about how many of the neural crest variant ferrets develop problems at earlier ages and how many have had a somewhat shortened life span compared with other ferrets so this is just a logical health precaution. What you would have started doing at 6 in medical care do instead at 5, and what you would have started doing at 5 start instead at 4 just to be safest. You can find these past conversations in the Archives. [Posted in FML issue 4565]