Genetic Effects of Strontium-90 on Immature Germ-cells in Mice

Abstract

IN a recent paper¹ we showed that injection of strontium-90 into male mice (CBA strain) caused an increased intra-uterine death rate in matings occurring within 5 weeks after the injection. This period of matings corresponds to effects upon spermatozoa, spermatides and spermatocytes. In order also to examine the effects of strontium-90 on spermatogonia we kept these males without females for another 5 weeks. From the 10th up to the 15th week after the injection the males were each week mated to 3 virgin females. Females mated the 10th week were allowed to give birth to their litters to produce F₁ animals for further tests. Females mated the llth–15th weeks were killed on the 18th day after the beginning of the mating period for analysis of the lethality among the fætuses. The results are presented in Table 1. It is obvious that in spermatogonia also there were some effects of strontium-90 causing an increased rate of intrauterine death.