Mouse Introductions

[Benturnip]

Good Evening to all,
I was wondering the best way to introduce 2 new juvenile females, a mother and her new litter of 11 babies (one week old), once they are old enough back into my general mouse population. Is it smart? Should I keep them seperated?

[Zouave]

Let me bump this to the top as I also want a mouse expert to comment.

I do not breed, but occasionally I get a pregnant female.

[Padfoot]

What I do with females is I put them together in a neutral areal (like a clean bin not used with any of the females before, or a bathtub). I let them interact there and watch them for a while. If there are no serious squables, I clean the cage where I intent on putting them very well, so there's not smell of any of the females, and put them in the cage and watch them for another while. It has always worked for me without any problems.

[Benturnip]

Should I do anything special when introducing the new litter of 11 in the general population based on their age?

[Padfoot]

Younger is easier to do, just make sure that the babies are weaned, so that they can escape if something happenes. If they are too young the stress of the introducction might lead one of the adults (be it their own mother, or the other one you introduced to them) might eat them.

[Benturnip]

I've heard that males and females should be kept seperate. What ratio of males to females is okay to put together in a 40 gallon tank?

[Padfoot]

The problem with keeping males and females together is that you'll have a LOT of babies. Also, the females won't have any rest between litters. This shortens the life span of your females. If what you are planning is to breed for feeders (or to sell to petstores), then I'd say that a male per every 6-7 females would be ok... but... remember that you shouldn't keep more than 1 male together... so having a huge mixed colony in a 40g is not a good idea. If you want a large colony in the 40g, then I suggest you to just keep a big colony of females in it, and keep a smaller tank or 2 with the breeders. Remember that you have to know what you will be doing with the babies before you start breeding. To know how many mice you can fit in a 40g, check out this page, just put the dimensions of your cage and it will give you the # of mice that can fit there.
http://www.geocities.com/funchy_crunchy/mcage.htm#calc

[Benturnip]

I have a breeder 20 and a 40 gallon aquarium the 20 is for the males (18) and the 40 is for the females (20). I have a 10 and a 5.5 for breeder tanks.