when breeding mice, how much do you make sure they weigh before breeding? do you keep males in with females? how old before you start breeding them? I have read as young as 4wks to start breeding but that seems so young to me. I know we only have one snake right now but I also know we have two mice and I would hate to feed off a preggy mouse, even though I dont particularly care for mice... one for sure is a male (can see little bits) they are pretty young though as far as i know... ill have to weight them this afternoon.