How Can I Tell the Difference Between Male & Female Mice?

Mice make wonderful pets for both children and adults, but unless you want to be overrun, it is important to make sure you have only males or only females. Mice are as well known for their reproductive prowess as they are for their gentle natures, and if you do end up with a male and female in the same cage you will soon have a cage full of tiny mice.

Things You'll Need

  • Sturdy surface
  • Mouse
  • Measuring tape
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Instructions

    • 1

      Remove one of your mice from the cage and place it on a sturdy surface. Locate the mouse's anus and its genital opening.

    • 2

      Measure the distance between the anus and the genital opening of the first mouse. Then remove another mouse from the cage and measure the distance on that mouse. The distance between anus and genital opening is longer on a male mouse than on a female mouse.

    • 3

      Feel the base of the mouse's tail. On an older male mouse the testicles will be easy to feel, but the testicles will be a bit harder to feel on a baby mouse.