To Tillie:
 
>Someone (I don't remember who) made the statement a couple issues ago,
>"Pandas are often deaf", and this got me thinking.
 
I'll bet it has the pandas thinking too.  But I think we are talking about
"panda-colored" ferrets, not pandas from the zoo.
 
>I have raised Australian Shepherds for about 15 years or so, and there is a
>genetic defect (Ocular Disgenesis Factor, sp?) that is seen in dogs born
>predominantly white, especially those with pure or nearly pure white heads,
>which includes deafness and may also include blindness.  So anyway, I got
>to thinking that maybe there could be a similar *problem* in Ferrets?
 
There most likely is.  It hasn't been proven, but there is enough anecdotal
information, especially from FML owners of color-diluted ferrets (that's the
medical term for them- albinos, blazes, pandas, silver mitts, black-eyed
whites, and so on...) to say that it is very likely.
 
The mechanism here is quite similar to your Shepherds, as it is in blue-eyed
white cats, who have a high incidence of hearing loss.  Cells in the inner
ear which contribute to hearing are actually pigmented.  When the cells are
not pigmented, they don't work.  Okay, now here's the important part - it is
not usually a lack of pigment, as many albino animals here very well, but a
defect in MIGRATION of these pigmented cells during development of the fetus
to their final permanent location in the ear which is defective.  This
problem also results in improper migration of pigmented cells to the iris of
the eye - resulting in blue-eyed (non-pigmented irises) cats, and pigmentary
defects in the eyes of other breeds, such as Dalmations and Australian
shepherds (in these breeds we often call the blue eyes "glass eyes").
Remember that there can be all degrees of defective migration in these color
diluted animals, so the lightness or darkness of the eyes is not a good
indicator of the auditory aptitude of your color diluted ferret.  Deafness,
however, is not a problem in non-color-diluted animals, such as sables.
 
I hope this makes some sense.
 
Bruce Williams, DVM, DACVP              Chief Pathologist, AccuPath
Dept. of Veterinary Pathology               [log in to unmask]
Armed Forces Institute of Pathology
[log in to unmask]
[Posted in FML issue 1674]