I would double-check your temps again and if they really are 88-90, bump it up to like 92 or so. If he really insists on being stubborn you can always try p/k mice instead of live. I bought a little baby from the IL NARBC back in october of this year and she didn't start taking meals from me consistently until late december, and she was fine, if a little skinny. She is however, a mouser. right now the priority is to get him eating, not worrying about what it is that he's eating. best of luck.