>What I am curious about, for all people who have had lots of ferrets or
>shelters, is were the ferrets who lived to an old age 8+ thin?  It would
>be interesting to take a poll.
 
One problem with just going from thinness is a problem that has also been
encountered more than once in relation to the human studies on caloric
restriction: that there is a lot more going on with thinness than just
the calories taken in.  For humans one of the most major problems is that
higher caloric consumption and sarcopenia have strong overlaps.  That can
also happen with ferrets.  Sarcopenia is a condition in which there is
too little muscle mass from too little exercise.  There is a spiral there
because low levels of exercise cause fat increase while fat increase also
often further reduces exercise.
 
Low levels of muscle mass have already been linked to multiple health
problems, from some malignancies through a pile of other things and on
to increased injury rates due to reduced balance (BTW, there is some neat
new work on a different approach to balance loss which will interest
some folks here with medical problems or elderly family members:
http://www.nytimes.com/2002/11/14/technology/circuits/14next.html .).
High activity rates are also good for mental stimulation and can add to
enjoyment of life for ferrets that way.  High activity rates and good
muscle mass keep ferrets and humans thin.
 
Obviously, it is hard to know off-hand when seeing a thin ferret or
person if the individual eats less, is more physically active, or both.
It may turn out that both can have positive effects, but tweezing the two
apart among humans is a very hard task which is not complete at this time
from what i have read, and the same difficulty would exist when presented
with thin ferrets.  Surveying thin ferrets would not separate caloric
intake from muscle mass and could give credit for benefits of an active
lifestyle to diet incorrectly.  It also easily might not work to then
say, "Well, we'll look only at thin ones who have lousy muscle mass."
because thin ones with lousy muscle mass are more likely to be ill, so
those illnesses would skew the survey in the opposite direction and make
caloric restriction likely look a degree of bad which also isn't likely
to be the reality *when nutrients and comfort are carefully taken into
account and the diet is suited to the individual's specific needs*.
 
This is a question which extends beyond what an annotated bibliography
can answer; real research is needed and until that exists I do think that
folks are best off discussing it with their treating vets and going by
what these independent, health-expert judges choose.  I do not consider
that to be an insulting opinion or a condescending approach; it's the way
I handle such questions myself.  I have 20 years of ferret background
and a related educational background but I am not a vet and knowing my
limitations is good for the health of my ferrets.
 
Sharon quoted:
>"Many studies have shown that aminals placed on severe calorie-restricted
>diets throughout adulthood live 30% to 40% longer than animals kept on
>regular diets.  The animals in these studies also show fewer signs of
>aging and have fewer chronic medical problems, including cancer."
>
>Of course, they don't recommend this for very old or ill animals (or
>humans).
 
Yes, there have been studies into caloric restriction which are
interesting, as i have said before, but a lot remains unknown including
but not limited to: if this approach will work out to be useful for
ferrets, if there are nuances such as this best being done at certain
ages, what medical conditions preclude use, how to best be sure to
balance in the essential nutrients and optimal comfort levels (As I've
also said before this may turn out to be best done with a future kibble
type that incorporates a decent percentage of indigestible matter if the
problems are overcome which might be associated with that such as bad
effects on urine pH to debris in the stomach, to who knows what depending
on the approach tried...), etc., etc., etc.  I don't consider this an
easy approach to try safely or comfortably (which is not to say that it
can't be done, just that it needs careful care for comfort and safety),
so i think that those who are interested need to discuss it with their
vets and if the vet says it is okay to try then they need to work out
beforehand with those health professionals or with a veterinary dietician
how to do so most safely and which individuals to not try it on.  (Of
course, not trying it on the health compromised ones will make it look
more good than reality, so in an unbiased study those considerations for
individuals couldn't be made if the study purported to address the health
of the general population, but I know that I wouldn't try something on
one of our ferrets if a vet said it would be dangerous, and I am sure
that is a common feeling here.  Just know that eliminating compromised
individuals definitely will skew results to the more glowing side.)
[Posted in FML issue 3970]