SOCIAL-ORGANIZATION AND AGGRESSION IN A GROUP OF OLFACTORY BULBECTOMIZED MALE-MICE

Olfactory bulbectomized and control male CF-1 strain mice were housed in separate, large, seminatural environments over a 30-day observation period. Control mice engaged in vigorous fighting behavior before a d ominant animal emerged. The alpha mouse established the floor area as its territory and vigorously attacked all other mice that ventured fro m the second tier of the enclosure to the floor. Lower ranking mice ha d numerous body scars, were much less aggressive, and engaged in a var iety of nonaggressive social interactions. In contrast, bulbectomized mice did not fight and roamed freely through all areas of the environm ent. These mice largely ignored one another, engaged in little or no s ocial behavior, and had no body scars. When two anosmic mice came into physical contact, they appeared startled and moved away from one anot her. These results, together with those of prior studies, indicate tha t olfaction plays a critical role in virtually all aspects of social b ehavior in male mice.