if your feeding prekilled rats just shove a calcium pill down its throat or up its...... thats what my uncle does, but he shoves like all in one vitamins for his snake, not just calcium. Ive never seen him do it but maybe theres someone here who can tell you more indepth about the procedure, as i think just sticking it in the mouth or whatever it would come right back out when the snake contricts. i think you gotta push it down the throat some or something.