Open-field parameters and maze learning in aggressive and nonaggressive male mice.

Significant differences were observed in thigmotaxis, ambulation, and latency to move (time to start ambulating) between highly aggressive (TA) and low aggressive (TNA) male mice. The former displayed more thigmotaxis, ambulated more, and had a shorter latency to move than the TNA animals. Also they voided a greater number of urinary spots and defecated less than TNA. Further they were superior to the TNA mice in maze-learning capacity. The tendency to enter inner partitions of the field as well as total ambulation increased after learning by TA mice. The training toward nonaggressiveness of TA mice suppressed aggressive responses, thigmotaxis, and the number of urinary spots but enhanced defecation. All measures returned to their initial levels after one month of rest. The attacking behaviour of TA animals increased both thigmotaxis and ambulation.