If you carefully watch your ferret eating its kibbled dinner, you will notice that it picks up a piece, then turns its head slightly to the side to bring the piece to the middle teeth. It crunches it a few times, swallows, and repeats the process. What the ferret is doing is to cut the kibble into small pieces using the carnasials, or cutting molars. The pieces are further broken into tiner bits using the tiny rear molars. Because the ferrets molars are so small, the major part of grinding the kibble is left to the cutting teeth, which are ill prepared for the task. Consider the effects of a kibbled diet on the teeth. Kibble is normally baked to about 8-12% water--10% is about average. When you consider the enamel in your teeth is 3% water and dry bone is about 7%, then 10% isn't much. While I haven't found any literature that rates the hardness of the kibble, from experience I can say its pretty hard, harder than some smaller bones. This is often touted as a "plus;" because kibble is so crunchy, it helps scrape the tartar off the teeth. The problem is, polecats and ferrets don't subsist on a diet of bones, and they do not have the bone crunching teeth found in the mouths of bone scavengers such as hyenas. Remember what polecats eat? We are talking small tiny bones, easily chewed, almost always less than a half inch in diameter, not big ol' elk bones. Ferret teeth are not designed for much chewing; they are designed to *cut* meat, tendon and bone. They do have a small molar hidden behind the last cutting teeth. The lower one is about the size of the head of a pin, and in the upper jaw its a little bit smaller than 1/8 by 1/4 inch (look at the capital "O" on your keyboard). Eating hard kibble does three things (and I have dozens of skulls to prove it). First, it wears down the back molars to the roots. Second, it wears down the carnasials to flattened stubs. Third, it forces grain paste (kibble n bits) under the gumline, causing inflamation on the surface of the bone. (I can't show you the pictures here, but Modern Ferret is likely to publish a digest of this series, and I *will* supply photos of all three dental problems). Yes, ferret teeth are designed to cut bone, but not *all* the time. Polecats and feral ferrets have pretty clean teeth, because the animal tissues (fur, bone, tough skin) polish and clean the teeth (those that have bad teeth fall into the ranks of garbage eaters, and have teeth as well kept as in bears, raccoons, and people who chew tobacco. Try and get that image out of your mind). Grains (because of the albumin) are as sticky as raisins, and small particles work their way under the gumline with each bite. This causes the gumline to receed, and the reactive changes of the bone cause the teeth to loosen. The food particles promote bacterial tooth decay, given footholds by the deep scratches on the teeth caused by the hard kibble particles as well as by the sticky kibble paste. But wait, you say, aren't raisins full of sugar? How is that similar to kibble? Because kibble is probably 40-60% carbohydrates, mostly starches. You don't realize this because it isn't normally listed in the analysis on the side of the package. Add up the listed analysis and subtract from 100, and you have a large percentage of "unknown and unlisted." This is primarily plant starches and sugar. Take one part starch, add a part ferret slobber, and you have instant sugar. Mix this with a sticky kibble paste and you now have the makings for a dental nightmare; just ask any dental pathologist looking at agricultural-era teeth prior to the Toothbrush Age. After comparing polecat to feral ferret to pet ferret skulls for the last year, I have almost a 100% identification rate for the pet ferrets based on nothing more than tooth wear and decay. One person from Britain donated a pet ferret skeleton to me, and I could not separate it from the feral ferrets nor the polecats based on tooth wear. That pet ferret was actually a working ferret, and ate mostly rabbit for the 12 years it was alive. I have about 20 pet ferret skeletons donated by USA pet owners, and, with a few exceptions, the teeth and surrounding bone are in horrific shape; dental abscesses, cavities, ground-down teeth and reactive bone surfaces are the norm. Softening kibble with water or broth will prevent the wear to the tooth, but will not prevent the stuff from sticking to the teeth or getting under the gums. To get rid of that, you need a tooth scraper and lots of bandaids. Of course, you could use of nature's dental floss; bone and fur. Bone and fur? Aren't these bad for ferrets to eat? Well, think about it. Remember what polecats eat? While they may not completely consume the entire carcass during each feeding, they do ingest quite a sizable amount of feathers and fur during normal eating. This is so common that one of the ways zoologists can tell what polecats eat is by looking at the bits of (washed) fur and feathers under a microscope and matching them to known specimens. The other way is to look at the small pieces of bone to make species identifications. This means that in wild polecats and feral ferrets, bone and fur are a typical part of the diet. So typical that the bulk of the poop *is* bone and fur. Yet these guys seem to do fine. So why the idea that fur and bone are bad for ferrets? The problem with fur probably relates to furballs, and the danger of plugged intestines they can cause. And this is indeed a potientially serious problem. The problem is not so much the fur as it is the rest of the diet. If you swallow fur and kibble paste, the paste tends to push through leaving the fur behind, which can ball up and plug things not meant to be plugged. In animals subsisting on a natural diet, parts of the carcass, including partially digested skin, tendons and bone, tend to help push the fur along the digestive tract. Kibble paste has very little undigested bulk, and the particle size of the fiber is microscopic, so it isn't very helpful in moving the fur down the road. Can fur have some sort of biological advantage for the ferret? Some evidence seems to indicate that the fur acts like thousands of minature brushes, sweeping the deep valleys of the intestinal tract clean of bacteria and other nasties. While just a hypothesis, it has yet to be disproven. If you compare the idea to current research in many other animals, including people, the idea that undigested bulk increases the intestinal health of the individual has a lot of support. Bob C and 20 MO Erudite Earbiters [Posted in FML issue 2313]