Genetic analysis of isolation-induced aggression. II. Postnatal environmental influences in AB mice.

Recently, we reported on two closely related inbred mouse strains, ABG and AB//Halle, that display extreme differences in isolation-induced intermale aggression. In the present article we investigated the influence of both maternal and social postnatal environmental influences. No effects were found of the postnatal maternal environment. Likewise, whether animals after weaning were housed together in same-strain or mixed-strain groups did not influence their subsequent aggressive behavior. We conclude that the aggressive behavior of ABG and AB//Halle is rather robust with regard to postnatal environmental modification and that the difference between the two strains is most likely due to only few genetic factors.