62 



ELBERT CLARK 



In another place^ I have described more in detail the changes 

 occurring in the nervous system of such fowls Here it was 

 also pointed out, in agreement with Frazer and Stanton and 

 others, that "The neuritis produced in fowls by a prolonged diet 

 of polished rice is, so far as the best evidence indicates, a neuritis 

 due to a deficiency of some food constituent or constituents 

 necessary for the maintenance of the metabolic and functional 

 activity of the nervous system. "^ 



In the paralysis of fowls brought about by an exclusive diet 

 of polished rice the medullated fibers of the sciatic undergo a 

 rapid degeneration. This degeneration, however, is much slower 

 than that produced as a result of transection of the nerve. More- 

 over, for the rice-fed fowls, the following conditions obtain: In 



jected to a process of 'milling' or polishing. "In this process the fruit wall or 

 pericarp, the layers subjacent to it (the subpericarpal layers) as well as the 

 embryo are removed," Frazer and Stanton ('11). These authors give the fol- 

 lowing as the average composition of polished and unpolished rice: 



Unpolished rice or red rice is rice which has not been subjected to the polish- 

 ing process, and which as a consequence still has the pericarp, subpericarpal 

 layers and the embryo. Fowls fed exclusively upon unpolished rice for long peri- 

 ods never develop neuritis as when fed exclusively upon polished rice. Further, 

 neuritis in fowls as the result of an exclusive rice diet can most frequently be 

 cured by placing the fowl on an exclusive diet of unpolished or red rice. There 

 are several qualities of white rice, which, aside from the quality of the grain, 

 are denoted by the amount of polishing to which the rice has been subjected. 

 As might be expected the most highly polished grade is the most effective in 

 producing paralysis in the fowl. 



2 Edward B. Vedder and Elbert Clark. A study of polyneuritis gallinarum. 

 Philippine Journal of Science, vol. 7, no. 5, Sec. B, p. 423. 



^ Richard P. Strong and B. C. Crowell have produced experimentally in man 

 a similar neuritis by the prolonged feeding of a diet of which polished rice formed 

 by far the main constituent. In one case which resulted fatally, the peripheral 

 nerves showed marked degeneration (The etiology of beri-beri. Phil. Jour. Sci- 

 ence, B, vol. 7, p. 271). John M. Little has also described bcri-bcri in man 

 resulting from an almost exclusive diet of white bread (Beri-beri caused by fine 

 white flour. Jour. Amer. Med. Assoc, vol. 58, p. 2029). 



