Cats and dogs are dangerous to mice and should not be kept in the same home as them. A mouse in captivity rarely lives more than 2-3 years.
The tame mouse is a social animal that depends on conspecifics to thrive. It is usually fine to keep two or more mice of the same sex together, and then you avoid unwanted breeding. Mice that are not littermates should be as young as possible when paired. Then they adapt to each other most easily.
Mice become sexually mature when they are between six and eight weeks old, and females come into heat approximately every five days. The gestation period is normally 20-21 days and a female mouse can have 5-6 litters of young annually, with 4-7 young in each litter. If you choose to have mice of different sexes together, it will almost invariably result in offspring. You are then responsible for ensuring that all the museum children get good homes.
Taking Mice on Holiday
You are responsible for ensuring that your mice are properly cared for, even when you are away.