I can't get my mice to mate?

Answer 1

There are several reasons I can think of, but as I find your question a bit vague, I don't know if any of this applies to your mice. The first and most obvious thing is to make sure that you have one mouse of each gender. The male's testicles are clearly visible under its tail, while the female of course has nothing sticking out under hers. The second thing to consider is the age of your mice. They could simply be too young to mate. Female mice are sexually mature at 6 weeks, and males at around 8 weeks. Also if you just recently introduced your mice, they'll need some time to get used to each other. It's also possible that she's pregnant and you don't know it yet. The gestation period of a mouse is between 17 and 21 days. Normally your female will show a week before she gives birth, but you can't always tell that she is pregnant. I have a female that gave birth to a single baby as it was her first litter and I couldn't tell at all that she was expecting.