the method above may work. in my experience with frog/toad eaters it doesn't. there are a couple of kinda gross methods you can use to switch them over. both only really work with f/t.
one is a toad slurry. freeze the toad first!! this will kill it. then blend it up and freeze it. ever time you offer a rodent, thaw out a small portion of the slurry and soak the rodent in it. the cut back on the slurry each time until you aren't using it at all.
another method that worked for me is by using the frog/toad skin to cover the rodent. again, freeze the animal first. then thaw it out and cut the skin off of the frog/toad. i used a scaple (i am a biologist and have lots of them). take the skin and put it over top of the rodent. if you are good at disection, you can quickly cut off portions of the toad without letting it thaw all the way. this will make the toad last longer. again, each time, reduce the amount of toad/frog.
if neither work right away, try the sented animal in a dark bag as said above. try your hardest not to revert to straight toad/frog. even if the animal took a rodent one week and won't take it the next week or two....don't go back! you will have to start all over.
billie bob, my male will only eat with the method you described. its pretty annoying!!