Here in The Netherlands a lot of ferret owners are giving them dead mice, rats or hamsters. The ferret eats them with hear and bones. It's actually better for their stomage, because lots of the so called ferret foods are not that great in quality (actually I don't know a single one that is of a really high quality). There are some kitten foods that are okay. Also, here we don't feed any chicken to our ferrets, especially not raw, because of the salmonella risk, which can kill your ferret.