Depends on the snake, comfortable ones can take full grown mice but the more skiddish they are the smaller and stinkier it needs to be. Try late at night with a small mouse or pinky rat, dip in saltless chicken broth or rub chick down on it, maybe even cut the head open. Theres a billion things you can do and alot of threads about it. I dont remember if you posted your set up before but make sure its small and very cosy! Alot of times its the enviornment thats keeping them from eating, but sometimes they just need some cohersing.
j
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"It's my snake, I trained it, so I'm going to eat it!" - Mad Max, The Road Warrior