Re: doing darkness One thing that we do is after dusk (sometimes before) we try to switch any lights around them to amber ones. Amber has the least effect on the body's own natural melatonin production. Sadly we can't do anything about some green and blue equipment lights except try to cover them. Blue is the most disruptive color and green is the second most disruptive color. Those are probably more readily available than they were when we got them because so much more research has come out on the importance of melatonin, but when we got ours we had to buy them from Low Blue Lights dot com https://www.lowbluelights.com which apparently still exists. Why does darkness matter? Increases in light exposure decrease the amount of melatonin the pineal gland produces and in turn that allows the pituitary to release larger amounts of LH and FSH. LH has been connected, by over a hundred studies, to the development of neoplasia (new growths) and hyperplasia (overgrowth of tissue) in adrenal glands and so to adrenal tumors among those studies (including not only ferret ones from veterinary study but also ones where ferrets were the animal models for human studies). BTW, a recent human study showed that the rate of human prostate growths was lower for those who live in locations that do not have much night lighting, using the NASA maps of ambient night lighting. There is a lot of info from resources like PubMed, Science News back issues, scotobiology professors, etc. BTW, notice that some of those studies looked tightly at portions of the endocrinology while others did overviews for a larger adrenal picture, but bit by bit each portion has been very well studied by one than one, alternatives considered and dismissed, and now people are down to learn more about any nuances. Sukie (not a vet) Recommended ferret health links: http://pets.groups.yahoo.com/group/ferrethealth/ http://ferrethealth.org/archive/ http://www.afip.org/ferrets/index.html http://www.miamiferret.org/ http://www.ferretcongress.org/ http://www.trifl.org/index.shtml http://homepage.mac.com/sukie/sukiesferretlinks.html [Posted in FML 6267]