google is your friend  http://www.thefunmouse.com/info/sexing.cfm
if your not used to doing it, you'd be better off comparing a number of mice, to check the distances beneath the tail; mice with a wider gap between both openings are male.
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Bachelor of Veterinary Science student, currently owned by a Kreffts shortnecked turtle in addition to 10 birds, 1 dogs and 2 cats (for now, anyway. population expected to expand)
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