This study presents, findings from investigations of the influence of chronic psychosocial stress on behavioural patterns and corticosterone levels in the four-striped mice, Rhabdomys pumilio. A modified resident-intruder paradigm was adopted in the study and involved the introduction of an intruder mouse (40-80 g) to a resident mouse (90-175 g) for 1 h for 5 consecutive days. Intruders interacted with different residents each day and behavioural responses were recorded. To determine if the resident-intruder paradigm induced an adrenocortical stress response, blood samples were collected after the last day of the paradigm via cardiac puncture from the control and intruder mice. The frequency of aggression (90±18 events dayG) received 1 from the residents and upright defense exhibited by intruders (43±9 events dayG) differed significantly over 1 repeated test days, however, there were no significant differences in the frequency of the resident climbing on the intruder’s cage (104±21 events dayG) Elevations of corticosterone levels were evident in the stressed mice. 1 Our data indicate that behavioural and neuroendocrinological responses may have important implications in the four-striped mice and in the understanding of psychiatric disorders
