I had great luck using Hills Prescription K/D diet, both kibble and small cans. I would take a cup of K/D kibble and put it in a container and add about 2 cups of water to it and put in refrigerator covered overnight to soak up water. I would then take a small can of K/D and put it in a blender along with the soaked kibble and puree it in the blender adding water if it was too thick, you want a gravy/soup consistancy. Use about 1/4 C soup or however much you can get your ferret to eat. Keep the rest in a container in refrigerator and use as needed. I believe I fed 2-3 times daily warmed slightly in microwave. This is good for about 3 days or so. You have to cut the protein levels when you have kidney disease, that is the purpose of the K/D diet and it has helped prolong the life of my ferrets with kidney disease. They do acquire a taste for K/D being consistant. If you have to add a few drops of ferretone to soup, I never did but it may help tempt them. Eleanor, Donald and the 10 ferrets (missing Cinnimini, Patcha and Buddy) [Posted in FML 7000]