I was down to two ferrets, one I loved to death (Mr. Stubby) and Ricky (who was not my favorite because he had killed my Sun Conure and bit the female ferret I had who died earlier in the year in the eyeball and half blinded her).  Mr. Stubby was a sweetie who let me hold him like a baby in my arms and pet him for awhile and then he wanted to run around and play. Ricky was a ferret I saw on Craigslist I had wrote about way earlier and he is a fat sassy boy as was Mr. Stubby.  

I noticed Mr Stubby wasn't as fat as he usually was  Then I noticed he wasn't eating like he normally did.  I attributed it to the food change I made.  But he still wasn't eating.  I took him to the Vet and he put him on medication thinking he possibly had Adrenal Gland Disease which is a common ferret disease. He had thinning fur which was one of the symptoms