Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Selection for large and small litter size of the first three litters in mice | Génét. Sél. Evol. 1985 17 2 251-264 Selection for large and small litter size of the first three litters in mice . de la FUENTE and F. SAN PRIMITIVE Departamento de Genética. Facultad de Veterinaria. Universidad de León. León Spain Summary A selection experiment based on female performance in 2 lines L for increased and L- for decreased total number of young bom alive in the first 3 births TNY-3 was conducted for 8 generations. Line c served as an unselected control. All litters were standardized to 8 mice. Responses and correlated responses were measured as a deviation from the control line. Heritability estimates for TNY-3 were from twice the dam-daughter regression and from the interclass correlations among half-sib families. After 8 generations of selection the cumulated response was young in the L line and in the L- line. Realized heritabilities for TNY-3 were in the L line in L- line and for divergence. Realized genetic correlations were between TNY-3 and first litter size between TNY-3 and second litter size and between TNY-3 and third litter size. Correlated responses per generation were g and g for 6 week body weight in the L and L lines respectively. Realized genetic correlations were between TNY-3 and 3-week body weight and between TNY-3 and 6-week body weight. Key words Mice litter size selection heritability. Resume Selection divergente sur la prolificite chez la souris à partir des résultats des trois premieres mises bas Cette étude concerne une expérience de selection sur la prolificite conduite chez la souris pendant 8 generations Une selection divergente L Ly avec témoin C a été réalisée sur les performances des femelles nombre total de nes vivants lors de leurs 3 premieres mises bas. La taille des portées était standardisée à 8 après la mesure de celle-ci. Les réponses directes et corrélées à la selection ont été .