Effects of X-irradiation of immature hamsters on growth and development of gonads^†

Hamsters were x-irradiated at 300 R on 1, 7, 14, 21 or 30 days after birth and sacrificed at the age of 33 days.

The body weight, testicular weight and the development of seminiferous tubules were severely affected by irradiation on day 1. The ovarian weight and the number of oocytes were more affected by irradiation on day 7 or 14. Effects of irradiation of immature hamsters on their growth and development of gonads appears to be permanent as irradiation of males on day 1 destroyed all their germ cells by day 33 and irradiation of females on day 7 caused their permanent sterility up to four months of age.