If I remember right, the major difference between rats and mice is fat content and taste. I've heard of snakes taking to one kind and refusing all others, too, but corn snakes aren't known to be finicky. Keep in mind, rat
pinkies are the size of mouse
hoppers (going by the mouse factory's rate chart), so the rat fuzzy is going to be way too big for a corn on mouse fuzzies. Otherwise, as long as the rat isn't too big for your amel, she should do fine on them.
Also, have you considered buying from a different place? I don't know where you're buying from, but
The Mouse Factory sells rats up to weanling size in 25 packs. You could easily have them send one 25 pack of rat fuzzies, and even one or two sizes up from that--and, hey, while you're at it, you can toss in food for your amel to fill up the box. The point is, you can buy in smaller quantities than 100. The only major difference is if you were getting this 100 minimum order of rats locally... Ordering from TMF, you'd have to have your order shipped.
Of course, there are probably plenty of other online rodent breeders that sell in smaller quantities than 100, but TMF is who I use, so, naturally, they're who come to mind and who I choose to suggest.
Seriously, though, if you were already planning on having your order shipped (and haven't ordered it already, lol), The Mouse Factory is worth checking out. Since they sell in such low quantity, you can pick up the size your RTB is on right now, as well as the next couple sizes up, so you're prepared... Remember, with 100 rat fuzzies, your corn may outgrow them before they're all done, too.
I hope I've been of some help, and, whichever way you choose to go, good luck with the RTB.. They're beautiful animals! =)
