Intermale Aggression in Laboratory Mice, Selected for the Cognitive Trait

Aggression level of male mice EX, which belonged to line, selected for the high scores of cognitive test solution [ability to extrapolate the direction of food bait movement after it disappears from animal view] was compared to that of male mice from control unselected population CoEX. The standard opponent test was used. At the start of selection [F5] EX mice were more aggressive, while at F10-15 the pattern of differences changed and CoEX mice were significantly more aggressive. These data could be partly explained by differences between EX and CoEX in their anxiety and reaction to novelty. Highlights: Selection for cognitive trait induced changes in the intermale aggression Intermale aggression is presumably related to anxiety level Less aggressive mice are not afraid of novel food Keywords: Intermale Aggression; Cognitive Abilities; Artificial Selection; Anxiety; Novelty; Mic