180 PTEROYLGLUTAMIC ACID 



microbiological assay in the basal diet) appeared adequate for egg produc- 

 tion and hatchability, it was not adequate for optimum livability of the 

 poult and storage of this vitamin in the egg. 



3. Monkeys 



The rhesus monkey is pecuharly susceptible to a deficiency of PGA, and 

 the symptoms are more similar to those of the human than are those of any 

 other species. They include anemia, leucopenia, oral lesions, diarrhea, ul- 

 cerations of the colon, and increased susceptibility to infections of the intes- 

 tinal tract. Re-examination of the literature shows that certain of these 

 symptoms had been described and credited to unknown nutritional factors 

 long before PGA was recognized as a vitamin. Day has termed this factor 

 vitamin M and in an excellent review on the early work in this field^^ points 

 out that "this syndrome, or certain manifestations of it, at least, have been 

 rediscovered and described every few years since 1919. The work has been 

 approached from many angles ; the diets used have been very different, but 

 what appears to be the same syndrome has been found in each." 



Wills and coworkers^^ were able to distinguish between the anti-perni- 

 cious factor in liver and the anti-anemic principle for monkeys, the anti- 

 pernicious anemia factor being precipitated by ammonium sulfate and the 

 monkey anti-anemia factor remaining in solution. 



A wide variety of diets have been used for the production of \'itamin M 

 deficiency (PGA deficiency) in the monkey. That used by Day and his 

 collaborators at Arkansas was composed of Labco vitamin-free casein, 

 polished rice, wheat, salt mixture, and ascorbic acid, and the known water- 

 and fat-soluble vitamins.^* 



a. Blood Changes 



The following symptoms have been described by Day^- and credited to 

 PGA deficiency. There is a progressive decrease in all types of peripheral 

 blood cells. The normal ^'alues for the rhesus monkey are 5.0 million RBC, 

 10,000 to 20,000 total leucocytes. A profound leucopenia involving all 

 white cell types is the most striking aspect of the deficiency. There is an 

 almost absolute neutropenia and lymphopenia. Total white cells drop to 

 2000 to 3000, and there is a marked agranulocytosis. This agranulocytosis 

 is thus similar to that observed in rats fed a purified diet containing sul- 

 fonamide. Limited data indicate a thrombocytopenia. Some animals show 

 a pronounced anemia, but others will develop a marked leucopenia which 

 is rapidly fatal without showing any severe anemia. INIinimum counts o\' 2 



^2 P. L. Day, Vilaviins and Honnoncs 2, 71 (1944). 



" L. Wills,' V. W. Clutterbuck, and B. D. F. Kvaiis, Hiochcm. J. 31, 21:56 (1937). 

 " J. R. Totter, C. F. Slmk(M's, J. Kol.son, V. Minis, and I*. L. Day, ./. Hiol. Vhcni. 152, 

 147 (1944). 



