Bearded Dragon Shopping List
I read somewhere that the best way to switch ball pythons to rats is to take two smaller prey items that would make up one usual meal; 1 mouse, 1 rat. You feed the mouse first and give it the rat immediately afterwards (letting you ball python take the rat itself of course, not forcefeeding or anything silly like that). Supposedly, once triggered, the feeding response is so strong that it will carry through to the 2nd prey item. After a few times, when your snake has grown accustomed to the taste and smell of rats you can just feed them appropriate sized rats from then onwards.
Is that what you meant?