Hybrid vigour and maternal environment in mice. II. Water escape learning, open-field activity and spatial memory

A combination of ovarian grafting and fostering was used to study the effects of pre- and postnatal maternal factors on adult behaviour. Inbred mice (BALB/c and C57BL/6) and F1 hybrids were compared to assess differential sensitivity to early maternal effects. In addition to the peculiar behavioural profile of BALB mice, results revealed the existence of a cognitive process in mice and confirmed the greater ability of F1 mice to adopt efficient escape strategies. Only postnatal maternal factors were shown to exert long lasting effects on behaviour, appearing to affect the general ability to react to a new situation rather than specific psychological functions. F1 hybrids proved less sensitive to such effects than inbred mice.