For an extra boost you can give your mamas eggs, yogurt, or Ensure.
Every time you open the rat bin, some mamas will pick up a baby and try to move them to a "safe" spot. Even if the babies get moved all about, the mother will almost always return them to the communal nest once the disturbance ceases.
I doubt she'll eat her babies.
I tend to leave babies and mother alone for at least 24 hours before fussing with them. The first few hours after birth are crucial for the mother to bond with the pups. But you can go on with your business in the room and the other rats.