Comportements maternels chez la souris: Telle mere telle fille?

Relations between mother' and daughter' maternal behaviour were surched by continuous recording of locomotor activity and time spent in the nest during the first six days postpartum in two isogenic generations of mice. The first generation was composed of either heterozygous Fl or inbred C57BL/6 (=B6) dams, both giving birth after ovarian graft to B6 pups. In each litter the maternal behaviour of a female was studied in the same conditions as for her mother. Even in developing in quite different environments, both groups of B6 daughters did not differ for the behavioural patterns under study. Links between mother' and daughter' activity during the nursing period were shown in one group by important negative correlations suggesting a feedbak regulation mechanism. This illustrate a possible way of passive hereditary transmission of acquired behavioural characteristics.