Sorry, I am behind on everything - very sick fuzzy ... I have had a few biters, one really bad one (adrenal male, testosterone overload) and one the owner was trying to return to a pet shop. In the former case, once the problem was identified and the (very large) adrenals were removed, as the hormone level dropped he became the greatest, most loving ferret ever. (He was only 11 mos. old and NOT a MF ferret by the way). I tried "everything" with the second one (also about a year old), and nothing seemed to help. Finally, one day when he struck, I started yelping LOUD, like a scared or wounded puppy. He looked horrified, and stopped immediately. After the 4th or 5th time, he had almost stopped, but occasionally would forget, and I would repeat .... after about a year, he stopped completely. I have only had to try this one other time, with a hard nipper, and it was successful - so no guarantees. By the way, the hard biter is the one with the health crisis. He is now six years old, and has been a great little guy. His days are numbered, but he has had a great life, and given me more than I have given him ... I wish you and your fuzzy well .... [Posted in FML 6373]