We have a white ferret/ yellow. Don't know why but he is. Maybe diet? We used a Ferrret whiting shampoo, Shepard and Green. Made our boys hair on his tail fall out and turn brown first. So be carefull what you use. I just deal with the yellow Ferret, than to take a chance and harm him again. I use Tomlyn Ferret shampoo or baby shampoo when needed. Wet rag helps between washings. Carol [Posted in FML issue 4632]