Also very good on dry kibble. Ensure Plus, Deliver, etc. If your ferret refuses to eat the basic soup mixture, you can add about to 1 ounce of either of these. Usually available in your pharmacy or supermarket. As your ferret will eat the soup better, discontinue this asap.
Sugar has a tendency to encourage bacteria.
Try to avoid anything with sugar. There are other additives, however, this basic recipe has worked wonders for many ferrets. It provides good quality protein and is easily digestible. Always check with your vet for any medical questions. Blend well in blender or food processor.