Renal failure does not appear to be associated with pain - nausea and
fatigue are the most common signs reported by human patients, and this
parallel what I have seen in a host of species over the years.
 
I have no problem advising prolonging the life of a ferret in renal
insufficiency - you will know when it is time.
 
With kindest regards,
Bruce Williams, dVM
[Posted in FML issue 3516]