9. Processed dry, extruded foods (kibbles) are nutritionally sound.
 
FALSE.  Proper nutrition is not just defined as having the proper
nutrients necessary for a healthy life, but also having those nutrients
supplied in proper amounts and proportions.  For example, a food may
exceed a ferret's calcium or phosphorus requirements, but if the RATIO
of one to the other is off for an appreciable period, or during early
growth, the result could be serious bone disease, such as osteoporosis
or rickets.  An additional example is zinc, which in trace amounts is an
essential nutrient in all mammals.  However, ferrets are very sensitive
to zinc levels, and a food exceeding zinc nutrient requirements could
easily poison a ferret.
 
The argument dry, processed foods are nutritionally sound is dependent
upon a single factor: the complete knowledge and understanding of ferret
nutritional needs.  That knowledge is not currently known, nor will be
known for any appreciable period of time.  It isn't known in humans,
despite decades of concerted effort.  Thus, any formulation postulated to
fulfill a ferret's nutritional needs is, at best, an approximation.  Call
it a best guess.
 
Kibble is a product designed to conveniently feed ferrets.  It is dry,
so it doesn't rot in the dish.  Most formulations lack appreciable odor
prior to consumption, as well as after elimination.  Because kibble is
made of powdered materials, if well mixed prior to extrusion, it
guarantees each bite will have the same nutrition as the last (it makes
me smile to watch herbalists insist on natural medicines because they
distrust processed and purified drugs, yet pour the dietary equivalent
into a dish and call it food!).  Kibble is NOT a food designed for
ferrets, but rather for the human who feeds the ferrets, who would rather
not worry about feeding a ferret several times a day, who dislikes
natural smells of foods or waste byproducts, and would rather not think
about what a strict carnivore actually eats.  We all need to understand
kibble is a compromise between what the ferret needs and what the human
owner wants.
 
The single most important ingredient in kibble is the starchy
carbohydrate that forms the bulk of the ingredients -- a necessary
ingredient to make the kibble.  Most kibbles are about 50% starch, some
exceed 60%, and the best kibbles are about 40%.  What this means is, even
if you are feeding the best kibble on the market, you are still feeding
a food that is about 40% carbohydrate, and carbohydrates are nothing
but long chains of sugar.  Would you feed your ferret a tablespoon of
processed, white sugar?  Why not?  You feed the equivalent each time
you pour kibble into your ferret's dish!
 
A food is not nutritionally sound if it lack nutrients, nor if it has
some nutrients in excess of needs.  Clearly, dry, extruded kibble
contains carbohydrates far in excess of a ferret's nutritional needs.
We assume such overfeeding is harmless, but the consequences of such a
diet is unknown in ferrets.  However, recently published studies have
shown a clear link between overfeeding starchy carbohydrates and
pancreatic problems in humans, carnivores, and many rodents.  While the
exact disease mechanism is unknown, the correlation between pancreatic
disease and excess carbohydrate in the diet have been confirmed.  I know
of two on-going studies that have preliminary data statistically linking
a carbohydrate-rich diet to increased rates of insulinoma in ferrets (and
other pancreatic disease in cats).  The study has several years to go
before it can be published (long term studies take a long time), but the
preliminary data is statistically convincing.  Regardless of published
and ongoing studies, one thing is clear.  As long as kibble is composed
of carbohydrates in far excess of a ferret's nutritional needs, it is NOT
a nutritionally sound food.
 
Bob C
[Posted in FML issue 3942]