i fed live large adult mice, then offered a small rat n mitch jus looked at me as if to say ok thats for u now wheres my mouse? he wouldnt even strike at it. so i fed him a mouse that was slightly smaller than he was used to the next day. once he was sched to eat again i offered the rat and BAM! he seemed real angry at it like he knew that was the reason he got a tiny mouse instead of a nice fat one hehehehe. good luck!