Abstract Intact vibrissal organs have been implicated as requisite for normal shock-elicited fighting in paired male rats and may convey the principal sensory information contributing to conspecific intermale aggression. Anesthesia of the vibrissal pad prior to each paired footshock exposure completely blocked the attack behavior of experimentally naive rats. Suppression of fighting was effective in all pairs tested over 14 daily sessions. Devibrissaed pairs also fought less than controls but gradually attained normall levels of fighting in spite of repeated clipping of all vibrissae to prevent significant regrowth. The results demonstrate an evident behavioral distinction between anesthesia of the vibrissal pad and removal of the vibrissae. General epidermal sensation from the snout appears to be necessary for initiating social fighting between paired males exposed to irritable shock.