Since the nursing mom is eating much more than she would normally, just cutting her back to her normal amount seems to work well for me. It is more important to have no contact with the pups I think which I don't like to do unless I have to. That is why I let them stay together until 7ish weeks. But at 5 weeks I cut it back to 3 visits per day rather than being there full time. Then 2 visits, then 1 visit, then goodbye. If the mom doesn't let them nurse, then all the power to her and let the food cutback begin. It is good for the pups to learn "no" in dog language. I almost don't want my bitches to spoil them but I always let them decide.