Who is a compatible partner for a male mouse?
The complex issue of social housing of laboratory mice was addressed by studying the housing compatibility of male mice with castrated males, or with ovariectomized females, for a period of up to seven weeks. Sexually mature males were shown to be socially incompatible with castrated males of the same age but to be more compatible with same age or older ovariectomized females (results varied according to the mouse strains used). These ovariectomized females could also be repeatedly housed with different sets of younger male mice, even after being briefly separated and again re-paired. Our data suggest that ovariectomized females could be used to establish a long-term companion group fully compatible for male mice group housing.