Use of SHIRPA and discriminant analysis to characterise marked differencesin the behavioural phenotype of six inbred mouse strains

Detailed characterisation of six inbred strains of mice commonly used in tr ansgenic and knockout research was carried out using a battery of behaviour al tests (SHIRPA) followed by discriminant analysis of the data. In the pri mary observation screen, DBA/2 mice were relatively irritable and vocalised during handling. C57BL/6 were hyperactive as measured by transfer arousal, arena activity and touch-escape tests. By contrast, C3H were markedly hypo active, had significantly enhanced grip strength and were also significantl y impaired on the visual placing task. In the elevated plus-maze, BALB/c mi ce showed the highest level of open arm entries and time spent in the open arms, indicating the lowest level of anxiety. There was a clear dissociatio n of strains on exploratory activity, as measured in the holeboard test and spontaneous locomotor activity (LMA). DBA/2 mice were hyperactive in LMA b ut demonstrated relatively low levels of holeboard exploration. None of the six strains learnt the water maze spatial learning task particularly well. C57BL/6 and 129/Sv demonstrated most ability and C3H showed no evidence of having acquired the task. The SHIRPA screening battery and discriminant an alysis of the data have enabled us to determine the relevant contribution o f a number of behavioural measurements to the marked differences in phenoty pe of mouse strains. These data confirm the importance of carrying out a co mprehensive profile in order to accurately characterise the phenotype of ge ne-targeted and transgenic mice. (C) 1999 Elsevier Science B.V. All rights reserved.