Dear DJ and Brenda:
 
Hindlimb weakness or hindlimb paralysis is probably the #1 most
non-specific sign (and one of the most frustrating) in ferrets.  It is
one of the earliest signs of disease, and it could literally be just
about anything.  A common cause is any disease that results in inappetence,
wieght loss, and mobilization of muscle tissue to supply energy for the
rest of the body.
 
All of the ruleouts that has been given are good, and the complete list
would probably be very close to a complete list of ferret diseases.  Judy
brings up a very valid point on hindlimb paresis in ADV - it may often be
the first sign of infection, as ferrets often pass through this stage
literally years before end stage renal disease due to AD is discovered.
 
If you can't find a spinal reason (and you usually can't) it's time to cast
a wider net.  Look for any type of disease in any organ system.  If you can
find it and treat it, you may see a significant improvement in hindleg
function.
 
With kindest regards,
Bruce Williams, DVM
[Posted in FML issue 3197]