I read BIGs archieves on tooth and teeth and was so surprised there was not alot on brown or dark teeth in a ferret. Not found even a white ring around the tooth either.. It makes me wonder if this is not so common... Read alot about broken teeth tho. We have one with this and will probably take him in.. Read Purina Cat Food fed to ferret's with dark teeth and this is what one of our rescues was on. We don't know for how long this food was fed for. Anyone else have knowledge on this? Debbie [Posted in FML issue 2924]