Baby-ish bp won't eat

[Bones]

Is there really a big difference between rats and mice??? The only difference I've heard is that rats are leaner (don't have as much fatty meat).

The reason why I said that is because he snake may have "imprinted" upon rats. I have an 8 month old BP who has imprinted upon mice, meaning that he will not eat rats. I've tried to feed him rats 4 times and each time, he has refused them.