| Abstract: | Groups of adult male mice of the Rockland-Swiss strain were paired 0, 2, 7, or 15 times with adult male stimulus animals rendered non-aggressive by extirpation of olfactory bulbs. All animals were castrated and tested until fighting ceased, following which each was given testosterone replacement and tested until fighting was reinstated. More than 50% of mice with no pre-castration fighting experience fought following gonadectomy. Castrated animals permitted 15 pre-castration pairings fought significantly longer than did animals of any of the other treatment groups. Finally, there was no difference among the groups with regard to the latency to resume fighting following the commencement of testosterone replacement. It is concluded that fighting experience enhances the persistence of the behavior following castration. |
