Theyre eating each other?!!

Question
I have three fancy mice for a year now.  Two of them are eating each other.  They are all female.  Well, they are not exactly eating each other.  It seems like they are grooming one another hardcore. They are now both missing an ear,  one has no hair/skin on one side of her face and they just look pitiful.  Your thoughts?

Answer
It sounds like you have been sold poor quality mice, there is no way mice should do that!

Although I don't recommend keeping mice in solitude I would separate them for now as they may end up killing each other.

I have come across this problem in mice before, quite often the problem is genetic. An irresponsible breeder will breed from a mouse with cannibalistic tendencies and have to 'rescue' the remaining babies. They will give them to a nursing mother and she will raise them as her own. Then at 2 weeks (can eat solids) they start to notice limbs, ears and tails missing from the young. Usually such breeders will leave the litter together to obtain the maximum amount of mice in the minimum amount of time. Of course interbreeding just concentrates these unwanted traits. They may sell a few of the 'intact' mice carrying the genes or give the deformed away to pet stores as snake food.

My pet store gives 'unwanted' (retired, etc) mice to me. A few years ago, I adopted 3 sisters with missing feet(their mother had gnawed them off) and they were very friendly to both humans and mice. A wild mouse managed to get in and 3 weeks later I had about 15 babies. Even though I handled them from an early age they were very jumpy and did not enjoy human company. 6 months later, the remaining 15 had babies (another wild mouse - even though I have 2 cats). The mothers ate a few young on day 1 which is expected. When they were a week old some of the mothers started eating them again, slowly.

Although not exactly like your problem, it may be an explanation for your mice strange behavior. I'm sure its NOT your fault so if something does happen please don't blame yourself.

If the mice have just started this habit recently, look at what you have changed in their diet/cage materials/position of cage/soap to wash the cage etc. Any change to their environment could be distressing them and may be cause for their behavior.

I hope it all works out, please let me know if you have any more questions. Good luck.