My ferrets are on this now. I get different foods routinely, cycling them and mixing different meats and ingredients. So far so good with this :

PETCUREAN 152332 Go Fit and Free Grain Free Chicken/Tk/Dk for Pets, 16-Pound

https://www.amazon.com/dp/B007JYQ39M/ref=cm_sw_r_other_awd_T85PwbXW4BDH8