No there isn't a scientific medical test for deafness so to speak. I've heard that its "possible" but it would be extremely invasive and stressful to the ferret (and expensive for you), and that only one or two places would even be equiped to do that. And I dont' have that on good authority. I'd say that there are reliable tests that you, yourself, can do. Home tests that may even be better than testing at a vets office. I say that because in a vets office a ferret is far too overwelmed with the new odors, sounds, sights, etc, to get reliable results from any tests there. Here is an addie to a site that tells you step by step how to test your ferret. http://www.geocities.com/wolfysluv/test.html If you find that your ferret is deaf, then go on to my deaf page. You may even want to join Amy Flemmings deaf ferret egroup for further info and some fun. The link to that group is on the main deaf site. Deafness can come not only from breeding with the Waardenburg gene that expresses itself in those sterotypical markings, but it can come from medication (Gentacin, Gentamycin), infection, and severe prolonged ear mite infestation also. Make sure you're little guy has no ongoing ear infection, or ear mite infestation if you find that he is deaf. I notice recently too, that I"m seeing more and more dilute colors with deafness in stores from the major farms. I'm seeing champaynes and light chocolates with none of the tell tail markings that are stone deaf. Very odd. On the other hand, I'm seeing more and more "fanciful" marked ferrets that are NOT deaf in stores. Which is good. I think maybe the Waardenburg gene is getting so washed out that the deafness factor is getting eliminated in some cases. The bad part is when the few that have that gene, but don't have the obvious markings, get the deafness because people don't think to look for it or consider it. Wolfy Please visit: http://www.geocities.com/wolfysluv/ for information on ferret deafness: http://www.geocities.com/wolfysluv/deaf.html [Posted in FML issue 3905]