You don't have to handle them if you don't want to though it makes it easier if you only have a small breeding colony to manage them if they aren't freaking out everytime you deal with them. I have some though that think I'm the spawn of Satan and I've raised the darn things from the day they popped outta their momma. Rats are just wierd LOL (or they are psychic and have figured out where those other rats went to).

Male rats won't generally hurt their babies but they sometimes will re-breed the female while she's nursing a litter, or sometimes not, the female may reject his advances. Really up to you if you want to remove the male or not, lots here have success both ways. Do make sure though that the offspring are seperated by sex by age 5 weeks or they will start jumping each other.

There's a ton of great rat breeding threads in the Feeder Forum but just holler if you have any questions along the way. Usually rats breed pretty easily and most females make excellent mothers.