The relationship between mouse killing and intraspecific fighting in the albino rat

Thirty albino rats were tested for mouse killing and then tested for intraspecific aggression in a paradigm that generates fighting without the use of electric shock. Mouse killers showed significantly more attacks and lateral blocks than did nonkillers; they also inflicted more wounds on their opponents. The two groups did not significantly differ on other often used measures of social dominance; they also did not differ in the display of stereotypic defensive behavior. The experience of fighting or of cyclic food deprivation did not induce killing in the nonkillers. The results suggest that there may be some relationship between mouse killing and intraspecific fighting.