I have asked two different researchers about the number of C57 mice of the same sex per cage, one of them used one per cage and the other used 2-4 per cage. I'm aware that isolation is a stress factor but they are territorial animals, that can be stressfull as well. I'm evaluating schizophrenia and autism behavior-like , what can be less worst for their behavior?
Dear Rhanna, overcrowding and social isolation are both factors of stress for mice. You should avoid leaving animals alone in the cage. On the other hand, you should not use more than 4-5 per cage, in order to avoid overcrowding, which can enhance aggressivity (if you are utilizing males, 4 per cage would be preferable).
Here you can find references related to overcrowding and social isolation (in the section Housing):
Article Behavioral Methods for the Study of the Ras–ERK Pathway in M...
I'm not sure how big your cages are, if the mice are from the same family and all ready know each other or if they are strangers. I use a 10 gallon fish tank, use carefresh/paper pulp type bedding, (no cedar due to respiratory issues), toilet tissue and paper towel holders and a wheel for fun. I use a water bottle and bowl for a nice dining area. (I take in special needs and homeless mice and rats as a hobby). I'm a member of Physicians for Responsible Medicine (write letters to stop unnecessary animal research). Your research sounds great. I hope this was helpful. They are such adorable little creatures. Mice have been coming in my house lately and my cats are catching them and bringing them to me alive. (They are babies so I keep them to make sure they are unhurt and able to run the wheel, etc. then let them go outside. I have humane traps but the cats seem to catch them faster, one of them kills the mice which is sad but when that occurs, the cats all scatter and no one takes credit for it). I'm careful due to hantavirus and other risks with wild critters.