Just reading today's FML and I find Mike's survey very interesting.
Several things ***really pop out*** (though they might be red-herrings or
might just reflect the composition of those with access to the survey, it
could otherwise be that they could well have bearing).  It would also be
interesting if readers of Modern Ferret filled in the exact same survey and
that data was added to get a larger and more varied sample.
 
I was surprised that so many had early adrenal tumors.  We've had a
slightly lower incidence rate at home (about a quarter of our's if three
types of adrenal disease are included) than I've been told is typical
through all these years, but our youngest with one was already into her
5th year.  All here who had adrenals knew each other, just as all who had
lymphoma back when we had three who got that knew each other, and all who
had cardiomyopathy knew each other.  That might mean squat; there is
research on and off as funding permits, though, into a possible infectious
disease link with lymphoma since clusters are so common and related
illnesses have had links found.  Feel glad that we haven't had the
younger ones.
 
Had a question about the fourth question but then realized that such a
later survey if done among owners might not make sense.  Sure would be
out-of-place in a survey which focuses on home conditions and care.  The
types of adrenal disease vary.  One of our's had a well-encapsulated
malignancy and another had adrenally based lymphoma.  These are quite
different from adrenal neoplasias, which two of our's had.  Obviously at
this point you are considering the basics with all types of adrenal disease
thrown together.  I'd been wondering if you might be considering trying
later to do a pathology results survey, but then you'd have to deal with
people getting the results and posting them accurately so that's probably
best done through vets.  It would be a heck of a lot of work, too, and I
sure don't know anyone who has more time to invest right now.  Any students
looking for projects and able to verify vets?  Don't even know if the vet
sample would be large enough to involve enough cases to make a difference
and the vets would need address and privacy protections like the Mysterious
Illnesses Vets' List provides with checks-back against sources like the
AVMA Directory to verify origins of posts.  It would be hard and involved
and might be best done in a later year to get a broader sample.  Don't
know.  Just mulling this over out-loud here...
 
The difference between the questions:  "Is the ferret consistently
exposed to natural light cycles?"  (Y 65% and N 34%), and "Where is
the ferret's primary housing?" (Indoors 100%) brings to mind questions on
how much the indoor cycles actually do mimic natural ones, as well as how
well these mimic the crepuscular light cycle of burrow-dwelling ancestors.
For instance, is there true, FULL, uninterrupted darkness like in a
burrow's sleeping chamber, or are there night lights, computer lights,
switch lights, etc.; when there are lights are they the green or blues
found to be so disruptive to melatonin cycles; are the daytime lights full
spectrum; are no lights ever turned on during the dark hours; are seasonal
patterns followed; when are the ferrets' times of greatest activity --
since that might influence when and in what amounts melatonin or some
unknown related factors are produced; etc., etc., etc.?  A person working
from this survey to look more deeply into the directions it indicates
perhaps would be interested in knowing how many adrenal growths are seen in
ferrets which are not lodged indoors and well as those in special indoor
setting which have these factors more tightly controlled than most home
settings permit to compare those two with more typical home settings.
 
The early neuter numbers are interesting.  Earlier works indicate that
this might contribute, though it's sure not a stand-alone.  I think it was
Alicia who mentioned to me a whole ferret with an adrenal growth (though I
might be mis-remembering who mentioned that) and they certainly have been
seen in late-neuters though perhaps at a lower rate.  Would be interesting
to later know how the rates seen here compare with the population at large
to calculate the percentage within each category separately as in A% within
total early neuters, B% within total late neuters, C% within total whole
ferrets.  Wouldn't be any surprise if this plays a contributing factor, but
would be good to have some firm numbers to see if it actually does or not,
since it might be a wild goose-chase or might be a partial answer.
 
The diet one jumps out, too, for further looking.
 
One thing a shelter person who I think asked then to remain anonymous
pointed out to me last year or the year before was that she'd noticed that
the ferrets which developed adrenal growths while in her shelter or which
arrived with them tended to be ones which hadn't had their vaccinations
as they should before reaching the shelter.  That lack of vaccinations
followed by being turned in to a shelter can bring all sorts of questions
into play.  It may be an indicator of a more stressful home, of lack of
care, of poor living conditions, of poor diet, even just plain of lack of
vaccinations itself.  It could even be a misleading artifact, but it is
interesting.  At least, I thought so, and I wonder if other shelters have
kept numbers on such a thing.
 
Mike's is a very interesting over-view about a very complicated problem.  I
hope that others will do more such surveys as time goes on and that these
multiple surveys are being collected by someone for later compilation and
comparisons; if not, yet, then may I suggest sending them on to Ferret
Geeks?  Have noticed that no one has brought into surveys pseudo-estrogens
such as are found related to some plastics and some pesticides.  (That
said, remember that these pseudoestrogens, like many other hypothetical
things currently under study have an interesting postulated mechanism but
lack the hard true research by veterinary experts needed to carve the
problem down -- which gets back to people funding such work through
reputable research facilities or research funding foundations, again.
See my other letter today.)
[Posted in FML issue 2865]