Message Number: YG6139 | New FHL Archives Search
From: RRC
Date: 2001-08-06 06:40:00 UTC
Subject: Bob C: "Ferrets" quiz Question

Three people asked me to comment on the idea that Cherrios and chopped
vegetables and fruits are good ferret treats. It appears to have been a
question in a recent issue Ferrets magazine. I haven't read the original
article yet, so can't comment directly. But I am happy to offer my
opinion on the matter in a general sense.

When discussing the diet of the ferret, I find it useful to forget that
our pets are domesticated wimpies, and instead concentrate on the
polecat progenitor. After all, ferrets ARE polecats in much the same way
that dogs are wolves and humans are just big apes with an attitude and
carrying weapons. So you have to ask yourself two basic questions. 1.
What do polecats eat? 2. What is available to feed ferrets that
approximate the polecat diet? You cannot easily answer the second
question without answering the first. Well, you can bottle ferrets into
bubbles and collect every last molecule of waste products and look to
see what happens when you fed them certain foods. When finished, you can
see if the ones still alive can reproduce. That works, if you have the
time, money and a number of disposable ferrets. But outside of that,
about the best thing you can do is to study what the wild progenitor of
our domesticated polecats eat and offer an approximate diet to ferrets.

The number one thing you notice when investigating the polecat diet is
they do NOT eat grains, especially processed cereal grains. Some
nutritionists have argued that polecats DO eat some grains that are
found in the gastrointestinal tract of prey animals, but realistically,
that is more than stretching the point on three counts. First, wild
European polecats are anuran specialists; they tend to eat a LOT of
frogs and toads. So much so that in many parts of Europe, anurans
constitute the majority of the yearly diet. I don't know a lot of frogs
and toads that eat cereal grains, although I admit some have a fondness
for algae. Second, there is a concept called optimal carnivory, which
suggests carnivores eat the most nutritious part of the prey carcass
FIRST, just in case they are chased away from their meal. Polecats will
generally eat the brains first, then turn the animal over and start
consuming muscle groups, heart, liver, spleen and kidneys, and then, if
enough time exists, they MAY eat the gastrointestinal organs. In other
words, there is little or no guarantee the polecat will get to eat those
"processed" grains found in the rodent or lagomorph gut. Finally, how
much grain can a mouse hold in their intestines? In relationship to body
weight, not a lot. You don't have to be able to do quadratic formulae in
your head to know the percentages are minor, and an insignificant part
of the diet.

Do polecats eat fruits and vegetables? Ferrets do; we have all heard
stories of ferrets stashing potatoes and devouring broccoli and going
bonkers over raisins. Well, ferrets have a built-in desire to eat
sugars, and polecats are no different. Sugars are the currency on which
the economy of the body runs. Sugars represent calories, and just about
every mammal has a predisposition to crave sugar (and salt). Polecats
have been recorded eating honeycomb (every year skunks raided my dad's
hives), and will certainly consume fruits when encountered. But if you
look at the physiology of the ferret, you discover they can manufacture
sugar from protein, without any adverse health problems. Humans can't do
this for very long; neither can most mammals. In most mammals, ketones
and other break-down products of protein glucogenesis can severely
damage the kidneys and other organs. In humans, it can lead to "rabbit
fever' and death. But the ferret is absolutely immune from the effects,
and can obtain their caloric currency from protein alone, which simply
means carbohydrates are such a small aspect of their diet that they
don't make a difference.

To be able to get nutrition from a vegetable, you must first be able to
grind the food to a pulp; ferrets cannot masticate their food--they cut
it into chunks and bolt it like a cat, and their teeth are formed into
cutting blades rather than grinding surfaces. Then you must be able to
have a prolonged gastric digestion, but ferrets have a gastric emptying
time measured in minutes (designed to process proteins as soon as
possible so the stomach can be rapidly refilled). In order to break down
the cellulose and get to the goodies, you need a long, complex
intestine, and a region inhabited by symbiotic bacteria; ferrets lack a
visual caecum and have a short, simplistic intestine. Since cellulose
sucks up a lot of water, herbivores need an efficient water-absorbing
large intestine to keep water requirements as low as possible; the
ferret large intestine is hardly different from the small, and is not
very efficient at resorbing water. The point of this exercise in ferret
digestive physiology is that ferrets are incapable of obtaining
nutrition from minced vegetables, and can only obtain minor amounts of
nutrition—mostly sugars—from fruits.

Still, not wanting the reputation of a fuss-budget, what about the
quality of the foods as TREATS? In tiny amounts, fed infrequently, they
are not life-threatening. So if your healthy ferret really likes them,
let them have some enjoyment. I wouldn't feed them to ferrets with
insulinoma, gastrointestinal diseases, or immunity problems (especially
the Cherrios). I would sincerely worry about the impact Cherrios and
fruits have on the teeth, especially for their role in the development
of caries or tartar, as well as their impact on ferrets with insulinoma.
They are absolutely NOT the best treats you can come up with. But they
can hardly hurt a healthy ferret if fed in small amounts, such as a half
a Cherrio or raisin at a time, or a couple of small chunks of melon
(which could be marketed as a ferret laxative). If your ferret is eating
the equivalent of three Cherrios a day, I would consider it excessive.

Better treats, and just as popular (once ferrets get used to them) are
meaty or oily foods (ferrets crave fat as much as sugar or salt). Mine
go bonkers over dried rainbow trout or beef, chunks of beef heart,
boiled beef ribs, and the ever popular frozen mice. Other treats include
chicken baby food (I WANT them to love it because I use it to feed them
medicines, so I give it as a treat), boiled chicken necks and backs (the
bone is harmless), flaked tuna, boiled egg, or tiny chunks of cheese.
The hard, fibrous fat you cut off your steak is a perfect treat, once
you teach your ferret it is edible. It's a tough connective tissue, so
as the ferret pulls and cuts it, it cleans the teeth. It is full of fat
(and essential fatty acids and vitamins), so it is nutritious. No other
food as as many calories per pound, so it is better than cream for
helping ferrets get their weight back after surgery or illness. Plus it
satisfies the ferret's instinct to chew. It may be impossible to
convince an older ferret of its value, but if you start with a kit, they
will rapidly become fanatical over the stuff. You can try chicken fat
with older ferrets, which isn't as fibrous so you may not get as many
benefits for chewing and teeth cleaning, but since a lot of ferret food
uses chicken, it might be easier to convince a ferret to try. Or you can
try my favorite trick; I get the ferret hooked on chicken fat, then feed
them some beef fat that had been stored in chicken grease. It fools the
ferret into thinking the beef is a chunk of chicken.

By the way, one of the main reasons ferrets "crave" vegetables,
crackers, breads, and Cherrios is because of the odor. Ferrets who eat
dry kibbled or extruded foods are olfactory imprinted on cooked
carbohydrates. The craving a ferret may display for a cracker or a chunk
of potato may have more to do with subsisting on a commercial diet
rather than because it is a "natural" behavior. Also, ferrets have
instincts to hunt and kill, but they have to be TAUGHT what animals are
suitable for those purposes by their parents, which include human
owners. If a kit sees you eating a carrot, and you give them a piece,
you are in essence TEACHING them carrots are good to eat. That is
exactly HOW polecats learn what foods are meant to be consumed; the
mommy polecat teaches them by eating some and offering the rest. I have
investigated a number of cases where a person will claim their ferret
loves veggies, and in almost every case, the human allowed their ferret
to nibble or eat the vegetable as a kit. Of course they will like the
food as a treat when older; they were taught it was a good food when
growing up! That is hardly a normal behavior. You can use this technique
to teach ferrets to try some foods. I bring the ferret up to my face so
they can clearly see what is going on, eat some of the food, then put
some in their mouth. It doesn't always work with the older ferrets that
are severely olfactory imprinted, but it works great with the young ones.

Personally, I would need some convincing before I would say Cherrios or
vegetables were good treats. Small chunks of fruit are somewhat better,
but not on my "A" list. They may not be bad in a healthy ferret if fed
infrequently in small amounts, but there are so many foods which are superior.

Bob C