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Mice/If this mouse is male, why hasn't he mated?


Male Mouse1
Male Mouse1  

Male Mouse2
Male Mouse2  
We periodically catch mice in the house; usually keep them for a month or so and release in wild after. We caught a number of mice this fall and decided to keep them until the spring. All caught mice appeared to be females. There way be a mix of house/field mice and deer mice. When I was cleaning the cage today, I noticed that the genitals of one mouse look different than the others. Picture is attached. Is he a male? If so, how could he live in the same cage for the past 3-4 months with 2 females and not get someone pregnant?

Dear Anthony,

You have a little boy (at first I was trying to figure out what difference you were seeing between these two mice : )  before figuring out it was one)

Assuming he is with does of his species, he may be a little clumsy, or he may not have virile "swimmers" :)

Still, it is a risk. I do suggest he be taken out. He might figure it out, or grow into his virility.

On the other hand, if all the girls are house mice, that is the answer. House mice do not mate with field mice.

squeaks n giggles,



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I can answer questions about raising mice and caring for them as pets, with knowledge from my 38 years of having fancy mice as pets. I have NO MEDICAL TRAINING and you should take a sick mouse to the vet; but if you simply can't, I will try to help you. I LOVE PHOTOS!!! I ALSO LOVE UPDATES! Let me know how the little tyke is doing later on, for better or worse, especially orphans. It also helps me to help the next person. Please first search first: use 'Natasha Mice Mouse' with whatever else your question includes. Or check out these links: **** YOUR FIRST MOUSE (my video; rough draft): **** TEN VIDEOS ON RAISING ORPHANS: **** SEXING MICE: **** And some GREAT MOUSE INFO SITES:


I have had mice for 40 years (since I was 5!). I raised them when I was a child but now I keep all females, and never fewer than three so that if one dies the others are not devastated, because they have each other.

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B.A., M.A., M.A. in Linguistics: Yale University and University of Connecticut

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