One thing I do is pull pinks the first day, maybe 2, an again two more a week later. This I feel helps the mom alot. I then wean the largest of the babies at 3-4 weeks and leave one or two a few days longer. This helps reduce milk production slowly and makes the moms more comfortable. Since I nursed I feel for the mom of huge litters that all get pulled at once, Ouch! If I am keeping some for breeders, they stay with mom til 5-6 weeks with no male in with. The less stress the better for best growth.
*Fila*