GENETIC INFLUENCES ON COPING BEHAVIOR IN-HOUSE MOUSE LINES SELECTED FOR AGGRESSION - EFFECTS OF THE Y-CHROMOSOME

Male wild house mice selected for Short Attack Latency (SAL) show an a ctive coping style to environmental challenges, whereas males selected for Long Attack Latency (LAL) generally exhibit a passive coping styl e. Previous studies showed that the aggressive SAL males develop routi nes more quickly and show more resistance to environmental changes tha n the less aggressive LAL ones; the latter behave more flexibly in non -social situations. Furthermore, using reciprocal F(1)s and backcross lines for SAL and LAL males, a Y chromosomal effect on aggression has been demonstrated. The aim of this study was to examine possible effec ts of the Y chromosome on behavioural flexibility. For this purpose si x genotypes (SAL, LAL, their reciprocal F(1)s and their congenics for the non-pseudoautosomal part of the Y chromosome) were tested for thei r behavioural flexibility in a Y-maze. Differences between SAL and LAL were reproduced. Congenic lines showed identical scores to their pare ntal ones. Regarding the reciprocal F(1)s, differences in aggression w ere not associated with behavioural flexibility. Therefore, it may be concluded that the Y chromosome does not influence aggression-related behavioural flexibility.