Short- and long-term effects of aggressive behavior on urinary marking in Mus musculus

Abstract

Male mice were housed in groups from 29 to 59 days of age (immature-grouping), or between 70 and 75 days of age (mature-grouping). Fighting and wounding were evident only in mature-grouping mice, which were classified as dominant or subordinate on the basis of wounding. At 116 days of age all mice were tested for urinary marking. Overall, mature-grouping mice marked more than immature-grouping mice, but among the mature-grouping mice, dominant and subordinate mice did not differ from one another in marking. In the second experiment mice were given a prepairing marking test, housed in pairs for 24 hr, classified as dominant or subordinate on the basis of wounding, and given a postpairing marking test 6 days later. Dominant mice marked more than subordinate mice in the postpairing marking test. The results support and extend previous findings that the short-term effect of social subordination is to reduce urinary marking. In subordinated mice, with the passage of time, marking may recover and may even surpass prefighting levels.