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]