There are some dog treats that may be available in your area pet stores: dried liver, heart, lungs and kidneys (sold in separate packages). Those, manufactured by a Canadian company, are not flavored. You can also find dried garlic flavored liver. I purchased the dried heart: I think it would be better than the liver which would be rich in vitamin A (I give my ferret diluted Ferretone) and because drugs might be accumulated in the liver. Those treats are great because: they are very rich in proteins, it is the dried organs so they are not processed, contrary to most dogs or cats treats that are made of mostly wheat or corn with some meat. It will not spoil if your ferret hides it. However, your ferret might still prefer raisins and you may have to get him used to those treats. Lorraine Tremblay & Pepe La Pew, Mukluk, Sanka, Presto, Snoreau & Boum Boum [Posted in FML issue 1734]