162 



NEUTRON EFFECTS ON ANIMALS 



blood cell counts, the absolute lymphocyte counts and the absolute neutro- 

 phil counts began to decline immediately after the first day of irradiation 

 (Fig. 1). The decline in the neutrophil count consistently paralleled the 

 total white blood cell count. The maximum reduction in blood cell values 



TABLE I 

 Hematocrit Values and Specific Gravity of Whole Blood and Plasma 



TABLE II 

 Blood Chemistry of Neutron-irradiated Dogs. Average Values 



occurred on the 5th day after completion of irradiation and was, for white 

 blood cells 98.9 per cent., for absolute neutrophils 99.2 per cent, and for 

 absolute lymphocytes 97.9 per cent. The eosinophil values declined 96 

 per cent. Reticulocytes disappeared completely from the blood. Plate- 

 lets were reduced 72 per cent. 



No definite change was noted in the percentage of basophils, nor in the 

 degree of poikilocytosis, anisocytosis, or basophilia of the red cells. Ery- 

 throblasts and plasma cells were seen only in the blood of dog #2 after 

 irradiation. 



The profound changes in the blood sedimentation rate following irradia- 

 tion are shown in Fig. 2. Blood taken 3 days after completion of irradiation 

 showed an increase in sedimentation rate, for a 24 hour sedimentation 

 period, of 683 per cent. On the 6th day, the increase was 1,860 per cent. 



The specific gravity of the blood, determined by the method of Barbour 

 and Hamilton (5), decreased progressively after irradiation. The specific 



