From what I have seen and read "True" Cushings disease (Hyperadrenocortism)
is rare in ferrets. Adrenal disease in ferrets is normally hyperestrogenism.
This could explain why the cushings test is unreliable (the are checking for
cortisol levels) and why the UT test is reliable (checking estrogen levels).
Just a thought,
Cray
[Posted in FML issue 2090]