Differential effects of prior dominance or subordination experience on conspecific odor preferences in mice

Preferences for the soiled bedding odors of familiar and unfamiliar conspecifics were assessed among male mice rendered dominant or subordinate by a series of resident-intruder encounters. Alpha males preferred the odors of their familiar antagonist most strongly. Subordinates, in contrast, showed strongest preferences for unfamiliar females and a weaker preference for alpha odors. When female odors were eliminated from the preference test, alphas continued to show the strongest preference for familiar subordinate odors while subordinates displayed roughly equivalent preference for the odors of familiar alphas and unfamiliar males. It is suggested that the apparent mild preferences of subordinates for dominant conspecific odors reflects fear motivated risk assessment. In contrast, approaches of dominants to subordinate odors seems to be appetitively motivated. Generally recognizable subordination odors may be useful to unfamiliar males in recognizing exploitable resources.