If they haven't been checked into there are some interesting geriatrics studies done partly by folks at Tufts that attribute more value to the higher levels of muscularity that are often found in lean folks than in fewer calories consumed. Of course, both could be useful things to have on one's side... Look into research into sarcopenia for those aspects. Anyway, it's an aspect that affects human studies of the long-lived, and certainly poor levels of muscularity have also been shown to have multiple negative health affects in multiple species and have downsides for ferrets such as some which Betty mentioned so well in her post. I agree that we do have to consider how over-weight -- including the extreme forms Betty mentioned which really are too common -- may play into bad outcomes, but having been too often through the difficulty of nursing very naturally gracile ones I know that leanness too often makes nursing harder and may shorten lifespans in that way, so I tend to prefer a middle ground when that is attainable. Then again, we make a point of taking in ones who already have major strikes against them so that causes our household to differ from many others. One thing that seems to work well with the ones we've had here as a predictor of a decent lifespan is good muscularity. Muscle levels are important enough in multiple studies of assorted species that they even can off-set some of the effects of over-weight, and when there is good muscularity they can offset some of those extremely well. If restricting diet then it may be more important to have some kibble in the diet from the ferret-specific high quality foods to make sure to not lack any essential micronutrients. >Recently a response from the FHL was crossposted here (it was on vaccine >duration). I wrote the original post to the FHL and because none of my >original post was forwarded I am sending it now. I appreciate you >forwarding these posts to this list for the benefit of others Sukie, but >in this case I feel the actual questions should of been sent along with >the reply. Thanks, Amy. Sometimes there are time or space constraints. One IMPORTANT thing that may be of use to you was a past discussion that vets were in about the problems with know what titer levels to treat as effective. You'll want to go to the FHL archives and read there. I've been hoping to have the time to search those out for the discussion on teh FHL but just haven't had the time. [Posted in FML issue 3958]