Just to add to what has already been stated. Heating the pinky to the point it almost splits open from the heat has always worked for me and picky newborns. Also make sure you use long forceps, hemostats or tweezers. You don't want your body heat confusing the snake. So the farther away you are from the food being offered the better. Sometimes they will lock onto your heat signature and not the pinkie. Hope this helps.
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Charles Koutris