Radiation-induced malformations after exposure of murine germ cells in various stages of spermatogenesis

We studied radiation effects in day 19 fetuses of the mouse strain 'Heilige nberger' after exposure (2.8 Gy, 137 Cs gamma rays, dose rate 0.28 Gy/h) of their fathers. We observed an increased lethality (exclusively due to prei mplantation death and early resorptions) after exposure of all stages of sp ermatogenesis with the exception of early spermatogonia. In addition, there was a significant increase in the frequency of malformed fetuses (gastrosc hises only); this increase was observed primarily after exposure of the mei otic stages. (C) 1999 Elsevier Science B.V. All rights reserved.