We've often found yogurt with active cultures to be helpful for ferrets who are ill or getting antibiotics but that the tablet probiotics don't always seem to make any difference. The current issue from Consumer Lab, which costs to join, has some useful info on probiotics and refrigeration. https://www.consumerlab.com/index.asp It seems that many probiotics require refrigeration BOTH before and after opening, and that many times when CL has done spot checks the tablets in stores do not contain the right amounts that they claim, very possibly due to improper storage. On their last check 17% did not have the amounts stated o on labels. The ones which do not require refrigeration are usually freeze dried and stored with blister packs to prevent moisture, or just are a few of the spore-forming bacteria or some yeasts. Liquid ones should always be refrigerated. They point out that if in doubt with a probiotic then refrigerate it, and if it says that it should be refrigerated then make sure that the store also had it in refrigeration. When buying online they suggest overnight shipment. What they mention may be part of the explanation for such variable results on this regard. Any mistakes in that paraphrasing are my own. CL is an excellent resource which I recommend. I find that if it even has one article that is applicable for our family it pays for itself rapidly, considering the costs of such items. Yes, I know that the old things say that ferrets lack intestinal bacteria to a large extent but recent work on commensal species of bacteria show that there are a number of tender anaerobic types that need to be found by their genetic traces. Most of that work is in humans, in rodents, and there appears to be some in dogs that I want to get to reading. There isn't any such work published done in any mustelid species, it appears. See also: http://pets.groups.yahoo.com/group/ferrethealth/message/17385 http://pets.groups.yahoo.com/group/ferrethealth/message/17383 http://pets.groups.yahoo.com/group/ferrethealth/message/17306 and articles in the separate FHL Archives. Sukie (not a vet) Recommended ferret health links: http://pets.groups.yahoo.com/group/ferrethealth/ http://ferrethealth.org/archive/ http://www.miamiferret.org/ http://www.ferrethealth.msu.edu/ http://www.ferretcongress.org/ http://www.trifl.org/index.shtml http://homepage.mac.com/sukie/sukiesferretlinks.html all ferret topics: http://listserv.ferretmailinglist.org/archives/ferret-search.html "All hail the procrastinators for they shall rule the world tomorrow." (2010, Steve Crandall) [Posted in FML 7446]