The litter of mice I have right now is 3 weeks old today. I'm feeding some of them off today. They are around 12g in weight. I'm only keeping four females from this litter to raise as future breeders. I was planning to pull them at 4 weeks old but might pull them sooner as they are already eating solid food and not really nursing from the moms anymore. The two breeding females are around 40g each (having been well over 50g each when pregnant). I do like to give my females a break between litters but I'm wondering how long to give them since I'm feeding off all but 4 of their litter. They raised 12 babies between them (was 19 but 7 were killed - first litters)