Message Number: YG2341 | New FHL Archives Search
From: RRC
Date: 2001-04-08 04:34:00 UTC
Subject: Re: Questions for Bob C.- RE:Fasting and Light exposure

Thanks (regarding Nosette and Sam Luc). I'll answer the first question
now and the other one later.

>First, in a recent posting you mentioned that you periodically will
>fast your ferrets for a day. I was wondering what the purpose of this
>is. I thought that it only took 3-4 hours for food to be passed as

I am essentially a ol' country hardcore Darwinian evolutionist. I
believe animals evolved on this rock over millions of years and their
physiology, behaviors and food choice reflect that history. Carnivores
have a long ancestry of eating flesh for nutritional and caloric needs,
and possess a unique physiology and anatomy to do so, including changes
to the digestive enzymes, stomach, intestines, pancreas, teeth, and
skull. The ferret is just a domesticated polecat, and polecats have an
evolutionary history which is ultimately older than that of most
carnivores—including the cat and dog. The weasel line, which includes
the domesticated ferret, is more than 20 million years old. In
comparison, the line that gave rise to modern humans is between 6 and 8
million years old, and modern humans have only walked the planet for
about 100,000-300,000 years. There are recovered skeletons of extinct
forms of polecats nearly identical to the ones living today that are
between 5-7 million years old; thus the dietary choice in these
carnivores not only has a very long history, but their anatomy and
physiology is also very well adapted to a diet of flesh.

In short, the dietary choice of ferrets was made long before human
ancestors climbed out of the trees, lost their tails, learned to walk
upright on the African Savannah, started stealing meat from wild
carnivores, invented tools, grew large brains, thought symbolically,
domesticated livestock, learned to grow cereals, and invented indoor
plumbing to control waste problems created by high fiber diets. Ferrets
are primary, obligate carnivores with a gastrointestinal tract so
adapted to flesh digestion that they can hardly tolerate the ingestion
of UNPROCESSED vegetable foods. A primary carnivore is one which eats
mostly flesh, and an obligate carnivore is one which must eat flesh to
obtain essential nutrients. For the most part, the two terms are used
interchangeably, but they are not strictly the same. Humans evolved as
obligate carnivores; vegetarians in the pre-Columbian world required
animal byproducts to survive, such as eggs, blood, milk or cheese. (When
I hear someone say meat "rots" in the human gut, or the human intestinal
tract is designed for herbivory, I have to wonder where they took
comparative anatomy and physiology and if it was an accredited school,
or if some scurvy dog is promoting a lifestyle at the expense of
historic accuracy. Vegetarianism is a political or moral construct, not
an evolutionary adaptation). Still, even though humans evolved as
obligate carnivores, we are NOT primary carnivores, and instead follow
an omnivorous lifeway. The ferret, however, is both.

The point to this is that, based on sound evolutionary principles, the
best food for ferrets is that which they evolved eating. And not just in
terms of essential nutrients, but also in terms of mental pleasure, oral
satisfaction, digestive need, and those non-digested parts which form
the bulk of elimination. To me, it is a package deal; a rodent goes in,
some parts are used, and others discarded, and all are important in
their own way. With apologies to Dr. Willard, while modern ferret foods
met most understood nutritional needs, they do not necessarily address
digestive needs. I say "apologies to Dr. Willard" because I do not want
anyone to think I dislike Totally Ferret. I think Totally Ferret is
cutting edge technology in terms of processed ferret foods. Dr. Willard
is caught between a rock and my hard head; even if he sold canned whole
mice in a light gravy, few people would be willing to put up with the
mess, smell (and sight) of the food, cleanliness requirements and poop
odor. I think he is doing the best he can to make the best ferret food
possible in a style that people demand.

Back when 2001: A Space Odyssey was a cutting edge movie with a light
show only a dead head could love, a commonly held, futuristic human
nutritional theme was the use of concentrated nutrients to feed people.
Using the anthropological technique of using movies/TV as cultural
mirrors, you saw this theme everywhere; in Soylent Green, many Star Trek
episodes, the Andromeda Strain, 2001, Lost in Space, even Woody Allen
flicks. It was a common idea that some day people would swallow a pill
and get everything they needed in their diet. But guess what? It doesn't
work that way, unless you WANT cancers and severe intestinal problems.
Humans evolved eating a diet of about 75-80% vegetable (mostly raw
fruits and vegetables, but some starchy tubers) and 20-25% meat (our
deep love of fat is reflected in our need to consume essential fatty
acids). Our gastrointestinal tract, physiology, and need for intestinal
bulk is proof of the fact, as is about 5 million years of recovered
bones broken, beaten and burned by humans or our ancestors. The absolute
most exciting aspect of my chosen career is the investigation of the
human diet and how it has impacted our evolution, both cultural and
physical. We are creatures of thought and technology because some dumb
ape once cracked a bone for marrow and taught their family to love fat.
That love of fat has fueled our shift from gathering plants to
scavenging, from scavenging to hunting, and from hunting to french fried
potatoes deep fried in heavenly tallow. In the last few thousand years,
human diet has shifted from something close to the evolutionary
hunter-gatherer diet to one heavily based on processed cereals and
starches. You can trace most human obesity, pancreatic disorders, bowel
disease and carbohydrate addiction to dietary changes caused by the
adoption of modern agricultural practices. The point here is that if
monkeying around with an omnivore's diet can cause such profound health
changes, what can happen if you mess with the diet of a primary,
obligate carnivore?

That's the big question, isn't it? But it is not an answer. To be
honest, no one yet knows the answer for humans, much less an animal with
so little dietary research as the ferret. Moreover, it is unlikely that
in our lifetimes the answer will ever be known; what little money is
available for ferret dietary research is used to determine WHAT ferrets
need, not to answer questions about the impact of dietary changes. But,
like I said at the very beginning, I am a hardcore Darwinian
evolutionist, so I tend to fall back on the polecat standard for my
answers. I consider the polecat diet, especially that of the European
polecat (Mustela putorius), to be the "Evolutionary Dietary Standard"
(EDS) for domesticated ferrets. This not only applies to the various
prey items selected and quantities consumed, but also the frequency and
method of feeding, the nutrients used and non-digestibles eliminated,
and those other behaviors and practices which define polecat predation.
EDS is a baseline for comparison, not necessarily a dogmatic standard.
For example, just because the EDS says ferrets kill their prey by a bite
to the base of the head, it doesn't mean ferrets should kill animals for
their supper. EDS is a baseline for comparison, a powerful tool to help
investigate what may be good or bad about current dietary practices,
nothing more.

So, what is the EDS for ferrets? Well, polecats evolved eating small
rodents, lagomorphs, amphibians, eels, insects, some birds, some fish,
some crayfish, and carrion. They are considered to be generalist,
opportunistic predators, but they frequently specialize in amphibians
and small rodents under the pressure of competition. Because the major
cause of death after predation is starvation, polecats evolved the
behavior of killing multiple animals when found together and caching
prey for future use. Polecats use a combination of random search
patterns and olfactory clues to find prey, with a sense of smell so
refined they can sniff out a hibernating frog in a foot or more of thick
mud. Polecats kill by biting the base of the skull or by gripping,
crushing and shaking the upper cervical vertebrae. Because brains are
fat and protein rich, in consuming larger animals, polecats tend to eat
brains first, followed by breast and thigh meat, then internal organs
and then the rest of the carcass. Polecats readily eat bone and will
cache larger pieces for future consumption. They eat long bones from the
outer epiphyses towards the medial diaphysis, but will crunch down
irregular and flat bones in a random pattern. Polecats eat from 4 to 6
small rodents or amphibians per week (on average) and fill in the rest
of their caloric needs by consuming small insects, worms, and edible
carrion. Because of their high metabolic needs and frequent difficulty
in obtaining sufficient food, they frequently rest or sleep, and will
occasionally slip into a very deep sleep where the metabolic rate is
greatly reduced. They frequently fast a day or two between meals when
prey is hard to capture. Polecats do not eat soybean, rice, corn or
other processed cereals or beans, nor do they eat foods which have been
cooked, pulverized, ground to gruel, or otherwise processed to pulp.
There is a lot more to a complete EDS, but you get the idea. Because we
have no real idea of the nutritive requirements for ferrets, much less
the digestive system requirements, creating and using the EDS for
polecats can help us at least identify those areas which may have
importance. At the very least, they can help us understand ferret
behaviors and make us better caretakers.

So, the reason I occasionally fast my ferrets is because they EVOLVED
with occasional fasting. While I can cite chapter and verse about the
probable health benefits of fasting that has been reported for dogs and
cats, I do not know of such research in ferrets. So, I cannot actually
give evidence that fasting has actual health benefits for ferrets, but I
CAN say it does no harm if the ferrets are initially healthy. I have
noticed it tends to help control the weight problem seen in older
ferrets, especially those raised on kibble. I fast those ferrets in my
care about 3 or 4 times a month, never feed them sugary treats (I have
long since switched to meaty treats and haven't offered a raisin in more
than 2 years), have cut out 70% of the kibble, and I have never seen a
hypoglycemic event in my brood. Anecdotal evidence is worse than no
evidence at all, and there is little research in this aspect of pet
care, much less ferret care, so I can't offer solid data to back my
actions. But as an evolutionist, I cannot ignore the EDS, either.

Bob C