114 



S. HATAI 



As to the high water content of the blood of the rats fed with 

 Sudan III we may attribute it to the condition of profound 

 anaemia. The blood examination kindly made by Dr. Rivas 

 (University of Pennsylvania) shows a loss of 12 to 40 per cent 

 in the number of erythrocytes. I have made an alcohol-ether 

 extraction of the dry blood and obtained the following results : 



This higher content of fat in the blood may indicate that the 

 elimination of fat from the blood has been much disturbed. 



GENERAL REMARKS 



Various alterations produced as the result of feeding Sudan III 

 to the growing albino rat have been presented. We found that 

 the alteration is not limited to a mere retardation of the growth 

 of the body and organs, but that the composition of these organs 

 is also modified. It is strange that most previous investigators 

 who fed Sudan III to rats, as well as to several other animals, 

 failed to notice any toxic effect of this dyestuff. This failure 

 was perhaps due to the fact that most investigators used adult 

 animals for their investigation, without very careful testing, 

 while Sudan III is strongly toxic only to the growing animals. 



Riddle, who fed Sudan III to young chicks, noticed a retarda- 

 tion of the growth of the body, as well as defective feathers. This 

 investigation by Riddle, on one hand, and my own, on the other, 

 shows clearly that Sudan III is injurious to young animals at 

 least. I have already mentioned the high resistance of the rats 

 whose bodies weigh more than 50 grams, but I have not tested the 

 reaction of the fully grown adult rats to Sudan III. I have, how- 

 ever, tried feeding Sudan III to female rats which were nursing 

 young. In these cases a toxic action of Sudan III was found 

 without exception. The lactating glands react promptly to the 

 dye, and failure of the secretion of milk is evident within a day 



