INTRAUTERINE EFFECT OF DAM ON PRENATAL DEVELOPMENT OF CRANIOFACIAL COMPLEX OF MOUSE EMBRYO .2.

Embryo transfer effect and intrauterine effect of the dam on prenatal development of the craniofacial complex of mice embryos were investiga ted with the use of embryo transfer and cephalostat. DDD strain embryo s were transferred to the three strains of recipients (DDD, C57BL, and DBA). The cephalometric observation of newborn offspring developed fr om transferred embryos was performed just after parturition. Dorso-ven tral craniofacial size of newborn offspring was calculated using value s of X- and Y- coordinates on a dorsoventral cephalogram. Statistical analysis showed that a significant intergroup difference in craniofaci al size between transferred and nontransferred groups as well as a sig nificant inter-strain difference among those of the three strains of r ecipients were observed. Thus, it was disclosed that embryo transfer t echnique might retard the prenatal development of craniofacial complex of transferred embryo and that the three strains of recipients contri buted unequally to the prenatal development of craniofacial complex of transferred embryo through each of their intrauterine environments as a prenatal maternal effect. These results indicated that the intraute rine environment of the recipient played an important role in the pren atal development of the craniofacial complex of the mice embryo.