I do think the quality of life does depend on the animal, owner and their emotional attachment to their animal and what their qualified vet thinks. If all the medical methods have been tried, then the above may apply. I'm sure many want to hold on as long as possible. Putting any animal to sleep can be a very hard decision.. I've had to do this and to be honest, I have cared more for my animal and cried more then I did any human in my life.. (hate to state this but it is true in my case). IMO- if all medical methods are tried, please consider how your animal is acting... A ferret who is still playful, eating and drinking, should continue to go on..We had an incontinent ferret, but I would not put her to sleep because of this. I really don't know all the factors to figure in when to put a ferret to sleep. I do trust how the animal is acting and what I have done to help my pet and what the vet suggests. If you have to put your ferret to sleep, please don't feel guilty because I know this is a very hard decision to make. Don't let anyone put you down for this. Just my opinion is all. Debbie [Posted in FML issue 2973]