My bitch had 6 pups she dealt with them herself I had no need to interfer with the feeding, so long as the mum is producing milk, the pups are feeding and growing(I weighed ours every day and kept a record) I see no need in getting involved, if you feel the pups are not thriving then of course get involved, the more the pups feed off the mum, usually the more the milk will let down, as far as I am aware, taking pups off the mum can actually assist in reducing the milk provided by the mum.

Mo