168 NEUTRON EFFECTS ON ANIMALS 



DISCUSSION 



Death of the dogs following 400 n cannot be attributed to any particular 

 change resulting from irradiation, nor can the changes be designated as 

 primary or secondary. 



The slight differences in the pattern of depression of the blood elements 

 from that in rats (12) and in rabbits (13) may be accounted for by the fact 

 that the dogs received greater amounts of radiation. 



The relatively small difference between the decrease in the hematocrit 

 and refl blood cell values does not indicate a change in the size of the 

 erythrocyte. 



The most marked change was in the blood sedimentation rate which 

 increased rapidly as the animals approached death. Preliminary work 

 indicates that changes in the fluid portion of the blood may be largely 

 responsible for the increased blood sedimentation rate found in these dogs 

 and in rats (12). This contention is supported by electrophoresis studies 

 (14) which have shown changes in the plasma components. 



The second greatest effect observed in the dogs was hemorrhages in the 

 lymph glands, heart, epididymis and subcutaneous tissues. This indi- 

 cates a severe effect on the vascular system, either directly or indirectly. 



The increased serum calcium following irradiation may indicate de- 

 calcification of the bones. An increase in calcium excretion caused by 

 fasting (15) indicates some dissolution of bony structures. Whether the 

 change in serum calcium was due entirely to fasting is not known, but it 

 may be, since food was refused by the dogs during the post-irradiation 

 period, probably because of radiation sickness. 



The increase in inorganic phosphorus following irradiation is consistent 

 with increased phosphatase values for these dogs (16). 



SUMMARY 



The administration of 400 n to dogs was followed by severe clinical 

 symptoms, such as loss of appetite, loss of weight, subcutaneous hemor- 

 rhage and edema, ulceration of the gums, lethargy and cachexia, coarseness 

 of hair and skin, and an impaired heart action. 



Hematological changes, such as leukopenia, neutropenia, lymphopenia, 

 occurred along with a reduction of red blood cells, hemoglobin, reticulocytes 

 and blood platelets. The rate of blood sedimentation increased. 



Serum calcium, inorganic phosphorus and the total nitrogen content 

 of the blood increased; the non-protein nitrogen content of the plasma 

 decreased. Blood chloride values remained relatively constant. 



Histopathological changes found were hemorrhages, destruction of 

 Ij'^mphoid tissue and injury to the testes. 



