I've feeding live since I got my snake and I noticed a few weeks ago that she got a scar on top of her head in between her eyes I'm guessing that a rat scratched her there last feeding. I tried feeding her a live rat again two weeks after but she refused to eat the live rat, so I killed the rat and left it in front of her hide to see if she would take it. Sure enough, about an hour later the rat was gone. So from now on, no more scars! Pre-killed all the way