Abstract: | We exposed the pups of three F1 genotypes of mice to a daily regime of cocaine by injecting their mothers (all C57BL/10J strain) on days 7–18 of gestation with 20 mg/kg subcutaneously. Pups of the cocaine and control groups did not differ on measures of maternal and pup health or size. Male pups were weaned and isolated at 21 days of age and their behaviors measured in an intermale aggression situation at about 80 days of age. Treated and untreated males of each F1 genotype were paired in dyads with either a C3H/HeJ (hawk-like) or AKR/J (retaliator-like) standard tester male. Standard tester males were not exposed to cocaine. Cocaine treatment alone reduced the overall level of aggression in dyads, and in interaction with genotype or the standard tester it altered the behavior of dyads in all phases of social interaction: the initiation, content, and outcome. Standard testers used as behavioral probes, differentiated cocaine and control males with respect to their stimulus and behavioral qualities. Aggr. Behav. 23:183–196, 1997.© 1997 Wiley-Liss, Inc. |