Soupies
Carnivore Care is great for weight gain or ill/post surgical ferrets.
Beechnut Meat Only Baby Food (NOT suitable as a staple diet, just as a recovery/emergency food): Chicken, Beef, Turkey
Holistic's Raw Soupie recipe for switching a ferret to raw
What is Soupies?
By Mary Wesker
Soupie is their regular food (kibble, balanced raw/raw grinds, or FDR), crushed or pureed (if balanced raw/raw grinds) and mixed with warm water. NEVER MICROWAVE SOUPIE. It cooks the food which further removes nutrients, and can alter the safety/nutritional value of many foods (making it go bad, over cooking, cooking bones in FDR or raw, etc)
If including egg, it should be limited one egg once a week, OR one egg twice a week during shedding season.
The best way to make soupies is getting a coffee bean grinder from the thrift store, washing it well, and using that for kibble or freeze-dried raw treats. Freeze-dried raw meals come in patties that easily break apart with some water and a fork. Alternately you can put some kibble in a container with some water and let it sit in the fridge and get soggy, but this can take hours and isn't the best choice if you need it in a pinch.
You can add small amounts of other healthy things, (1/8 of a teaspoon of salmon oil per day if offering daily, carnivore care for ill ferrets, one to two eggs per week, meat only baby food like Beechnut stage one, or a low sodium, low veg stock, no garlic chicken broth) but if using salmon oil or egg it must be eaten right away, and what is not eaten within roughly 30 minutes should be thrown away and the bowl sanitized. It should not be left out for longer than 4 hours.
Soupie is good for delivering meds, switching foods, helping maintain blood glucose in ferrets with Insulinoma who need meals every four hours, and for infirm, elderly, or very young kits (ease of digestion). Kits under 12 weeks should have softened kibble, if kibble fed. I soften kits’ food up to 16 weeks to avoid anal prolapse.
There is no danger to offering soupie daily, soft food damaging teeth is a myth. However, you will still need to brush their teeth as you would with kibbles or FDR.
Soft Food DOES NOT DAMAGE teeth (these links pertain to cats, but keep in mind ferrets and cats have near identical dietary needs, and they have near identical teeth and jaws)
http://felinedocs.com/dr-steven-bailey/to-feed-or-not-to-feed-–-canned-food-–-that-is-the-question/