Things You'll Need
- Mouse food
- Two plastic bins/cages
Instructions
Wait until the pups are 21 days old. Do not attempt to wean pups before this age. Some pups should be weaned closer to 28 days; you'll need to check specifics for your breed by reading books or websites about the particular breed of mouse you have.
Check the gender of each pup. It can be difficult with young mice, but you can visually check the ano-genital distance to determine the males and the females. The ano-genital distance will be longer on male pups and closer together on female pups.
Remove the pups from the mother's cage, and place them in two new bins by gender. The males will have their own cage now, and so will the females. While it may be tempting to skip this step to save space, it is important that the mice be separated both from the mother to keep the pups from being eaten and from the other gender in order to avoid early sexual reproduction.
Put food onto the floor of the bins. The baby mice need to be able to get to it easily, so for now avoid putting it into a food dish. Keep track of how much food you've put into the bins.
Isolate the new bins. They need to be placed in an area removed from the mother. A higher or lower shelf in the breeding area works well for this.
Tag each box with relevant information about the mice. This includes the number of pups, the date they were born and the date they were separated. If you have more than one breeding at a time, you'll want to note the mother as well.
Watch the mice carefully over the next several days. Make sure that some food and water is being consumed, and that the mice do not appear to be losing weight.