If there is little evidence in print, is there practical experience? To test this idea, I obtained a copy of the current AVMA membership roster, and used a random number table to select veterinarians (excluding well known ferret vets to minimize bias). I called these randomly selected vets, and if they acknowledged they saw 20 or more ferrets per month, I asked a series of questions that included feeding bone to various animals and ferrets. I continued to randomly call vets from the list until I talked to a total of 100 vets (I'm a sucker for N statistical populations). Among the many things I found was that if the vet disapproved of feeding bones to dogs, they generally disapproved of feeding bones to ANY animal. Conversely, if they approved of feeding bones to dogs, they generally had very few objections to feeding bones to ferrets. What does this mean? It could mean personal prejudices were governing the vet's attitude towards feeding bone to ANY animal. It probably also suggests the information available is inconclusive and animal health care professionals are basing decisions not on demonstrable facts, but on unsupported opinion. In other words, in the absence of definitive evidence, vets do what everyone else does=97they rely on their personal belief systems for the answer. That is, personal prejudices. The bottom line is, WHEN PRESSED, most vets admitted they hadn't actually seen problems from ferrets eating bone, or perhaps--in a very few cases-- just an occasional problem during an entire career. Sometimes, a vet will hear that a ferret consumes a natural diet that includes bones, and will suggest a bone fragment caused a particular problem, but never confirms the diagnosis with X-rays, surgery, or necropsy. These types of hypothetical, unproven diagnoses are often seized by ferret owners as factual, and the incident becomes part of the anecdotal evidence decrying the practice. For example, I know of a specific incident where a vet made a diagnosis of a bone fragment puncturing the bowel, causing bleeding and infection that ultimately killed the ferret. This diagnosis was based on x-rays that showed small bone particles in the bowel. The suggestion of bone-caused death was made, and the incident would have become part of the argument against feeding bone if it weren't for the owner muddying the anecdotal waters by insisting on a necropsy. When the necropsy was performed, it was found the poor ferret died from an intestinal blockage caused from eating sponge, which did NOT show up on the x-ray, BUT was unmistakable on necropsy. Bone had NOTHING to do with the death! An even more interesting finding was when I followed up on the story; I found the vet continued to insist the ferret died from eating bone, even though a copy of the necropsy results refuted the finding. In another case, bone was blamed for causing esophageal and gastric bleeding, which a necropsy proved to be from an ulcer. The problem with anecdotal evidence is that it is more proof of observer bias than scientific fact. While anecdotes abound, veterinary literature lacks significant reference to problems in ferrets caused by eating bones. As stated before, there are only a handful of confirmed problems caused by bone eating in carnivores, much less mustelids. As a whole, data confirming the dangerousness of ferrets eating bone is a statistical phantom. That is not to say some people aren't convinced eating bone has harmed their ferrets, nor is it implying that problems don't occur. My only implication is that if it was as dangerous for ferrets to eat bone as some people imply, not only would there be better evidence, but there would be demonstrable evidence capable of withstanding statistical analysis. There isn't. As I said: it is a statistical phantom. Bob C [Posted in FML issue 4155]