>Dear Dr. Williams,
>
>In a cross-post on today's fml (Oct 6th), I read the following in one of
>your responses:
>
>> "Low-protein diets are of some benefit in prolonging life in animals
>> with renal failure, but do not appear to have these benefits in older
>> animals with normal renal function."
>
>This has me somewhat confused, because I remember reading in one of
>your posts a year or so ago (sorry, I didn't keep the post), that you
>you advised a low protein diet for ferrets over 3.5 or 4 years of age,
>to help preserve kidney function into old age by putting less demand
>on the kidneys.  (Or at least that's how I remember it, and it made
>sense to me at the time.)
>
>My six ferrets range in age from almost 4 to almost 7.  They have been
>on a diet of Totally Ferret their entire lives.  After I read your
>advice last year, I started feeding them a 50/50 mixture of regular TF
>with the senior formula TF, hoping it would be beneficial to them.
>Actually, I first tried switching them to 100% senior formula, but they
>all started losing weight, even the eldest - even though they were
>eating heartily - so I decided on mixing the foods.  Since all my
>ferrets live together and eat out of the same dishes, it would be very
>hard to feed different diets to some of them.  In fact, they also all
>get Prozyme mixed with their food, since one of them has Eosinophylic
>Gastroenteritis, and my vet recommended it for him.
>
>The bottom line is that I just want to do what is best for them, to help
>them live long, healthy lives, so I'm now wondering what that is.
 
Dear X:
 
You are very perceptive, and correct about this change of opinion.
However, even I change my mind, often as a result of new information, or
because of some research that I have done when posed with a new question.
 
In the case of low-protein diets, this is still an area of some
controversy in veterinary and human medicine.  It has only been a matter
of a few years that researchers in small animal medicine have stopped
endorsing low protein diets for all animals and only for animals already
in renal failure.  (I usually take my guidance in the pathophysiology of
chronic renal disease from Dr. Delmar Finco of the University of Georgia -
one of my professors in school and one of the most highly regarded renal
experts).
 
My ferrets have never had a weight loss problem with feeding geriatric
diets, and switching them back to a higher protein diet probably would be
more stressful than they need.  I certainly understand the problems
associated with trying to feed ferrets different diets, and few people
have identified a solution.  However, if you are mixing regular and
geriatric diets, you are still feeding a regular diet.  But if they are
doing well on it, then let's stick with it.
 
With kindest regards,
Bruce Williams, DVM
[Posted in FML issue 3569]