Also, just to add, I have NEVER had a rodent (rat, mouse, hamster) that cannibalized her young because she was lacking in dietary needs.
Behavior like that (cannibalizing, aggression towards pups, aggression towards you) should be culled immediately. if that is a problem and if you plan to keep any of her offspring (that she didn't eat) they should be observed for the same behaviors/culled.

Good luck!