male mice fight

Question
QUESTION: i have 2 very young male mice which are brothers. they seem to get on fine the majority of time and have thier fights but there are 2 parts to the cage and if one mouse enters the other part the other chases him and makes him squeek. so he cant play on the wheel. what should i do? we have only had them 3days. thanks

ANSWER: Dear Hayley,

Male mice, even brothers, usually cannot live together. They will fight to the death. They need to be in separate cages side by side so they can communicate.

Pet stores should know better than to sell two males. Maybe you can return them for two females (three is  better).

squeaks,

Natasha
<:3  )--~

---------- FOLLOW-UP ----------

QUESTION: they arent drawing blood is this still bad? http://www.fancymice.info/behaviour.htm i found this site which says that 'Chasing - another way of showing dominance and perhaps also claiming territory. The mouse chasing (the dominant one) may also 'hold on' to the mouse in front with its mouth/teeth on its back near to the tail. You can often tell that this has happened because you will see a small bedraggled patch of fur where the fur is damp from the saliva.' which seems to be perfectly normal? they are still continuing to chase when one enters the other territory. thanks

Answer
Dear Hayley,

It"s ok if mice chase each other and squeak. Mounting and holding each other down is fine too. What's not ok is:

1. Drawing blood
2. If one mouse is depressed
3. If the chasing occurs enough to wear the mouse being chased out, or
4. If one mouse can't access either food, water, the nest, or the wheel (you meant he just sometimes can't get to the wheel? Can you give them two wheels?)

Now it sounds like the issue is pretty mild right now. However, these are young mice, and they are brothers. If any males get along, it's young brothers. But if it is starting now, it can only get worse as they grow up. It is unlikely that the fighting will stay mild. It isn't a good sign that they have separate sections of the cage; mice should sleep together.  You can keep them together as long as the above is not true, but you need to be prepared to house them separately if it gets worse.

I hope things stay mild. Best of luck.

Squeaks,

Natasha
<:3. )--~