1: Live can be frequently more enticing. I'd get yours on rat pups ASAP. Mice won't be big enough for long.

2: It varies snakes to snakes. With my kingsnakes and retics, I've noticed that really young ones (about 6 months or younger) seem a lot more likely to eat in shed than older ones.
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We wouldn't have 6 and a half billion people if you had to be beautiful to get laid.
6.6 African House snakes
3.2 reticulated pythons
.1 corn snake
4.2 Florida Kings
1.2 speckled kings
1.2 ball pythons
0.0.1 Argentine boa