Figure 4.

Serum corticosterone (CORT) levels from mice in the different social dominance groups measured under different cage change conditions. Groups of mice were sacrificed either immediately after the home cage change and 15 min recording session to identify Dominant, Intermediate and Submissive mice (Cage Change condition) or 48 h after this timepoint to measure CORT from undisturbed cages of mice (Control condition). Mice in the Dominant and Intermediate groups, but not Submissive group, showed significantly elevated CORT levels relative to controls (#P < 0.05) after cage change and social dominance interactions. After cage change, Submissive group mice showed significantly lower levels of CORT compared to other two groups (**P < 0.005 versus both groups) following this session. Bar graph data are shown as mean ± s.e.m.