Here at the shelter I mix Felidae cat food with the EVO cat food.? I was using the cat EVO before the ferret formula came out, so never got around to switching.? (If anyone has any thoughts on the difference between the two, I'd like to hear it.? The ingredients seem pretty identical.) Yes, we did have some diarrhea when we made the switch.? But everything went back to normal.? I was able to switch about 25 ferrets of various ages pretty quickly?to the EVO/Felidae combo.? Liz ...in the Company of Ferrets, Inc. www.ferretasylum.org MN [Posted in FML 5948]