Make no mistake about it: this type of dental wear is pathological. The teeth are not designed to withstand it, it causes or contributes to other dental disease, and it probably causes enough pain or discomfort to reduce a ferret s quality of life. Think about it for a moment. If you have a worn tooth, you know how sensitive it can be to pressure; bite something hard and it hurts like the blazes. Ferret teeth look different from human teeth, but the basic design is the same: a pulp cavity containing a nerve and blood vessels, surrounded by dentine and covered with enamel. Imagine how it would feel to a ferret with worn carnassials trying to chew hard kibble: each bite could potentially cause discomfort, even pain, leading to mild anorexia and weight loss. You should note the rate of wear is not a linear relationship to time; it is a curve. The reason is because enamel is harder than dentine and when the outer enamel shell wears away, the wear rate increases: the less enamel, the faster the rate of wear. This is the main problem with using tooth wear to estimate the age of ferrets; ferrets with worn teeth are generally estimated to be older than they actually are. This is also why you cannot use dental wear rates determined from wild populations to estimate the age of pets; the wear rates are not correlated, and because of diet and other factors, may not be congruent. There is no doubt that the dental wear rates and type of wear is a direct result of eating a kibbled diet. The characteristics of wear and location are as distinctive as a fingerprint. Of course, diet-mediated wear is harder to determine in young adults and may be impractical in juveniles, but distinguishing it in older ferrets is a snap. It is so clearly apparent from a forensic point of view that I am convinced the analysis of wear facets can distinguish a lost pet ferret from one living in a feral state, and after my European and New Zealand trips, I will publish such a paper describing exactly how to do it. Once you know what to look for, all you would need is an impression of the ferret s teeth and a few measurements, and you would know without a doubt if the ferret was a lost or abandoned pet, or if it was truly feral. How can you protect a ferret from the wear caused by a kibbled diet? You can t; there is not a kibble on the market that doesn t cause tooth damage. It is not that kibble was designed to wear down a ferret s teeth; it was designed to be poured in a bowl and not spoil. In the manufacturing process moisture is driven off the food, making the particles resistant to bacterial growth. It is made that way because people want to pour a bowl-full of food and place it on the floor for a week and never worry about it. The problem starts when you drive off the moisture: the resulting product is quite hard, which is why it is so crunchy. Because the components of kibble are small, as they harden they turn into organic sandpaper. If you feed your ferret kibble, the damage will be inevitable. The best you can do is to soften the kibble before serving. One way to do this is to soak the kibble in water or broth, but generally, this causes the pellet to disintegrate. Another method is to place the kibble in a bowl, spray a light mist over it, then warm it in a microwave; the water vapor will help to soften the kibble without making it fall apart. Or, you can simply pour kibble on top of Bob s Chicken Gravy or some other suitable duck soup. The kibble should absorb enough liquid to soften. Cage bite wear is another type of dental attrition found exclusively in pet ferrets, with 23.8% of the skeletons displaying the trait. Most of the wear is limited to the canines and front premolars, which can take a nasty beating. As the ferret hooks their canines around the wire and tugs at the cage, the metal is rubbed against the enamel, sandpapering it away. Once the enamel has been breached, the softer dentine wears at a faster rate, notching the tooth. When enough of the tooth is abraded, it is prone to fracturing. Sometime prior to that point, the tooth generally becomes sensitive, and the ferret may shirk away from cold or slightly hot foods. If the canines are sensitive, even if they are not used to consume kibble, the discomfort may be enough to reduce their desire to eat or drink, and they can lose weight, exacerbating other problems. There is not a lot you can do to stop a ferret from cage biting in an attempt to escape; I ve tried all kinds of things that rarely work 100% of the time. The only thing that I ve found that ALWAYS works is to let the ferrets free-roam. However, most people cannot allow their ferrets to live outside a cage, so some attempt to stop cage biting is in order. You can extend the time the ferret is out of the cage, but that won t stop them from cage biting while they are inside it. One person told me they recycled a model railroad transformer to run a weak electric current through the wire; not enough to hurt, but just enough to tickle the ferret, making cage biting uncomfortable (like the feeling you get when you lick 9-volt battery terminals). I think this has potential: perhaps an electrical engineer can come up with some plans that can safely perform this task and post them on the FML. At this point in time, perhaps the best solution is to buy cages where the screen is 1/2 inch or less. This prevents most ferrets from hooking their teeth over the wire. Using cages with plastic-coated wire might also help reduce the rate of wear, but I doubt if it will stop it; the plastic quickly wears through at popular cage-biting locations. If you have a ferret that refuses to stop biting the cage, you might want to consider moving it from a wire cage into wood one with small wire screening, or have a cage built out of perforated Plexiglas. If you don t stop cage biting, the front premolars and the canines will take a beating, wear at an accelerated pace, and ultimately fracture. They become sensitive to touch, and it is possible, although I didn t see it, that exposed root canals can become infected, spreading disease to the rest of the body. Check the back of the canines and the front premolars regularly, and if you think you have noticed wear or notching, bring the damage to the attention of your veterinarian. Most animal dentists can quickly rebuild the back of the canine with acrylic material, both restoring it as well as protecting it from further damage. In the next installment, I will discuss missing teeth in ferrets. Bob C Questions?: [log in to unmask] Communications? [log in to unmask] [Posted in FML issue 4519]