NEUTRON EFFECTS ON ANIMALS 



171 



atrophy and shrinkage of the seminiferous tubules appear some time after 

 irradiation, the length of the lag period depending on the dose. 



B. Histopathological Changes. Four groups of 20 or more male rats 

 each were exposed to 11.3, 50.4, 113 and 355 n units of radiation respec- 

 tivel,y in Box Xo. 7. Immediately after irradiation and at intervals up to 



TABLE I 



Effect of N^eutron Irradiation on the Weight of Rat Testes, Spleen and Liver 



200 days, one or more of the surviving animals from each group was killed 

 by a blow on the head, the testes wei-e removed and fixed in Bouin's fluid. 

 Sections were stained with hematoxylin and eo.sin. 



In the control animals there were occasional atrophied tubules in which 

 nothing but Sertoli cells and syncj^tium remained, as well as occasional 

 multinucleated giant cells and vacuoles among the germinal cells. The 



