Since the question's been raised again recently... The real story on those two blue dots in your ferret's ear by Dr. Judi Bell reprinted by permission from the WNYFLFA Ferret Chatter, Sep/Oct '95 Marshall Farm spays, neuters, and descents ferrets at 6-7 weeks of age. Because they heal so quickly, and regrow the hair at the incision sites before they leave the farm a week later, a system was devised to prevent unaltered kits from accidentally being sold with the ones that had had surgery. A simple tattoo, consisting of two black dots, is placed in the right ear at the time of surgery. The dots mean that the ferret has been both descented and either spayed or neutered, depending on sex. As the kits grow, the dots grow and soon look blue instead of black. The tattoo was not originally intended to identify Marshall Ferrets for anyone but Marshall Farms personnel. However, these dots have become an unofficial trademark of Marshall Farms' ferrets. There is nothing distinctive about two simple dots, which can and have been copied by other ferret breeders. Most of the time, if you see a ferret with two black dots in its right ear, it will be a Marshall Ferret. If the dots are any color but black/blue, or are in the left ear, of if there is a single dot in either ear, the ferret came from somewhere else, even if the owner has documentation showing the Marshall Farms name. Documents can be copied or transferred, and the ferrets have no unique marks to absolutely identify them. [Posted in FML issue 1477]