This is actually something I wrote for someone on the FHL, but it can answer questions that a couple of folks on the FML posed, too. ----- Well, first off they are not known to get the rhinoviruses that we call human colds, though they can catch influenza (which may seem like a cold if a human has only a mild case), and we have had a bacterial sinus infection in the household years ago that they turned out to be able to get. Such infections are not caused by being exposed to the cold; they are from exposure to the infectious organism which causes the disease, so isolation during contagious times, many hand washings, facial masks, etc. can be useful in stopping the spread. Ferrets actually do well in the cold, and I sure that many a British ferret keeper will tell you of their ferrets out in the winter. They actually have more of a problem with too much heat. There are special types of heating pads made for animal use or for being able to be covered. Using standard ones for those uses can at times result in a fire. I am sure that is something you would rather avoid. I can well recall the day a friend who is a fireman dropped by to relax and told us of a fire that day in which a person had tried to use a standard heating pad to heat seedlings and instead wound up burning down the house -- total loss. If you are worried then give them extra blankets. They will use the ones they want and toss off the rest. [Posted in FML issue 3631]