| Abstract: | Videotape recordings of male mice group-housed, individually-housed and cohabiting with females, were rated for their agonistic behavior in a “standard opponent” test. Previously mated male mice showed more fighting than isolated or grouped males. Marked differences in other social and non-social behaviors, which could not be accounted for in terms of increased fighting, were not evident. These results suggest that agonistic behavior may be usefully studied by examining male mice that have cohabited with females. One obvious advantage is that such mice cannot be dismissed as being “socially deprived,” as is sometimes claimed for individually-housed mice. Other advantages are that aggressiveness is induced quickly, at high levels, and the mice appear very sensitive to hormone manipulation following castration. |
