baby mice cages

Question
my baby mice are 2 weeks old. when i sex them i plan on putting a male
mouse in with its father Luigi. Luigi's aquarium is 8.5 in. by 16 in. is that
enough room for two male mice?  my other spare cages are a 15 gallon tank,
a 10 gallon tank, a SAM cage the one you can connect tubes to, and a 10 in.
by 16 in. plastic cage. how many males or females could fit in each of these
cages?  i think there are 5 males and 8 females but at this age it is hard to
tell. do you have any suggestions on separating the mice in pairs or groups
between the sexes.

if you would like to you can see my mice at
www.youtube.com/user/8tasksoctapus and look under my videos
thank you,
luke

Answer
Dear Luke,

I found your mouse videos and love them!  I subscribed to you ('usmousie').  I don't usually get to meet my distant patients!  I also had a mouse named Angela recently- she was a white long hair silky rex, incredibly beautiful.  Great mice!

The more room a mouse has, the better. Thus I would use the biggest cages.  Each cage should have a wheel-- you may have taken it out to make the video, but I want to make sure.  There is a small wheel called a 'silent spinner' which fits those little cages.   The SAM cage is most fun, of course; you just have to be prepared to clean out the tubes pretty often, because mouse pee on plastic stinks.  A 15 gallon tank will hold a lot of happy mice. Certainly 6 or 8 mice would live there well.  You probably only need to use two (large) cages for all your females.  I wouldn't want to put more than three adults together in the little cage.  More mice in a large cage is better per cubic inch than fewer mice in smaller cages, because they like a lot of space to move around and explore.  

Because the father is out of the cage, he may not recognize his baby and thus may not welcome him.  Males very often fight.  Sometimes it's just a lot of chasing and squeaking, but if someone bleeds, it's time to separate the mice.  Littermates have the best chance of getting along if they are never separated.  

Often a male mouse doesn't get along with any other male.  Then the poor fellow has to live alone (unless your vet 'fixes' mice-- but most don't).  It is crucial that he be near the other mice because they actually converse in almost constant squeaks too high for us to hear, and mice are very lonely alone.  Also, if a mouse lives alone he needs a lot of attention from you.  You are his only mouse friend.

If you are going to keep a lot of mice, it might be worth investing in something more exciting for them to live in.  You can buy a wire three-story cage with ladders and put different things on each floor (make sure nothing can fall off, especially not a toilet paper roll).  Baby mice can get out through the bars, though.  A mouse can get through any opening that will fit its head, because their rib cages actually fold to let them through!  You can also make a cage out of a large plastic bin by cutting out most of the top and replacing it with 1/4 inch galvanized steel mesh ('hardware cloth').  Making similar windows in the ends gives them the ventilation that none of the other cages have (that's the disadvantage of aquariums) and gives them an area to climb as well.

Have fun with all your mice.  You have done a great job so far-- the babies are nice and tame even though they just opened their eyes.  Check my archives or write again for info about other mouse topics.  By the way, separate them when they are about 4 weeks old because mice are already sexually active at 4 1/2 weeks!  The little boys will even be interested in mounting their mom.

squeaks n giggles,

Natasha