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Boy or Girl?

21 15:33:29

Question

Boy or Girl?
We bought 2 mice at local pet stores at separate times (2 months apart).  Both times we were told the mice were female.  The second mouse (Maizy) to our surprise had baby 22 days after we brought her home.  At first I thought maybe she was pregnant when we got her, then we decided to look closely at the first mouse (Lina) to see if we could tell if maybe it was a male.  After looking at pictures on the internet of male mouse genitalia, we are still not sure!  I went to a pet store today and checked out some male mouse, they were all DEFINITELY male, but our mouse doesn't have such obvious features.  I've attached a photo.  What do you think?

Answer
Dear Debbie,

I have to say I am amused to receive an X-rated mouse picture.  You've got a little boy there.  His testes will grow more obvious when he is a little older.  He may be a late bloomer.  Mice also gestate for exactly 21 days, so that's a pretty suspicious sign too.  

If they stayed together after the birth, you can expect another litter 21 days after the first one.  At that point the first litter will be almost weaned.  Two weeks later those babies can begin to mate.  Three weeks later... you see the problem.  You'd better separate them as quickly as possible.  The pet store really ought to help out with the babies, though it isn't so very simple because somebody has to tame them.

You will find answers to many questions you may have by following this link:

http://en.allexperts.com/q/Mice-3824/2008/10/Breeding-Mice-1.htm

Please let me know if I can be of any further assistance.

squeaks n giggles,

Natasha