in order to investigate the effects of pre-ovulation x-ray radiation on fertilization , initial cleavage and post-nidation development , chinese hamster dams were mated with normal males after exposure to 200 rads of radiation during the primary maturation period , and cytogenetic studies were performed at 2.5 , 3.5 and 10 days after fertilization ;
C0678723
maturation
C0015914
fertilization