This is just a guess and is probably wack but my snake hasnt eaten in about 3 months and before he stopped feeding he was eating all black rats. My dad had brought home a 20 pound bag of frozen rats (all white or white/black). Since then he has probably only eaten one white rat. This is probably stupid as I said before but could the color of the rat have anything do with him not feeding? Im going to get ablack rat next week and see if he takes it.