STUDY OF MATERNAL EFFECT ON DENTOFACIAL GROWTH IN MICE.

哺乳动物的生长受到遗传和环境影响的影响。本研究旨在探讨胎儿期和产后母体对小鼠牙面生长发育的影响。首先，用DDD、C3H、C57BL和DBA 4个品系的小鼠进行胚胎移植实验，发现胎仔大小与牙面大小呈负相关，而与孕期呈正相关，对小鼠胚胎的牙面生长有显著的应变效应，相同的DDD/QDJ品系的胚胎移植到四个受体品系的小鼠胚胎在调整的牙面大小上存在显著的种间差异。其次，对大品系DDD小鼠和小品系C57BL小鼠的饲养实验表明，哺乳母鼠的应变效应对仔鼠的出生后生长发育有显著影响，且哺育母鼠DDD品系饲养的后代的体尺显著大于C57BL饲养的后代。这些结果表明，出生前和出生后的母体效应对小鼠的牙面生长起着重要的作用。

Mammalian growth is snfluenced by the genetic and environmental effects. The purpose of the present research is to investigate the prenatal and postnatal maternal effects on the dentofacial growth in mice. Firstly, the embryo transfer experiment with DDD, C3H, C57BL and DBA strains of mice showed that there was an inverse relation between the litter size and dentofacial size but a direct relation between the gestation period and one, that there was a significant strain effect on the dentofacial growth of mouse fetuses, and that a significant inter-strain defference in the adjusted dentofacial size of the mouse fetuses developed from the same DDD/Qdj strain of embryo transferred to the four strains of recipients. Secondly, the fostering experiment with the large strain of DDD mouse and the small strain of C57BL mouse showed that the strain effect of nursing dam affected a significantly the postnatal growth of the offspring and that body size of offspring nursed by DDD strain of dam was significantly bigger than that of offspring nursed by C57BL dam. Theses results indicated that the prenatal and postnatal maternal effects playd an important effect on dentofacial growth in mice.