fighting females

Question
Dear Panya,
yesterday I just bought some mice (2 males, 2 females)for the first time and put them together in a new cage. The males immediately started fighting so I had to remove the injured one, but now a female is picking on the other female too by nibbling its fur and pushing it. Then the nibbled mouse runs away into the house and it would be a long time before she comes out again. Are they really fighting, and would this continue or would it just stop once the mice spend more time together? I don't want to separate the attacked mouse but I am afraid she will always be bullied. Unlike the other two she is not active and doesn't play with them. What should I do? Please help.
PS: the male mouse that got hurt and the female that's being attacked are both albino mice, while the others are not. Might this be the reason they get picked on by the other mice?

Answer
I apologize if my answer seems a bit jumbled, I have the flu and its difficult to think straight!

The males were fighting for the females and the females are competing for the best male. If you want to breed mice (putting males and females together will inevitably do so) then I suggest waiting until you are very familiar with mice and can find homes for the offspring.

It is possible they got picked on because of their fur color. I had an albino with a 10 other darker colored mice and they bullied her so I had to put her in a separate cage and bought a few lighter colored mice for company.

You should only keep single sexes together unless you want to breed. You will need two separate cages, the larger the better for the males as they fight for territory. It is possible the girls will stop fighting once you remove the boys.

If you are worried about any of the mice getting injured and are still unsure about what to do you should take them back and keep one sex only (I recommend females as they don't smell as bad). It helps if they are all from the same cage and are approximately the same size and age. Ask the pet store which mice get along with each other well and handle them before you buy

Please feel free to ask any more questions. Good luck.