178 PTEROYLGLUTAMIC ACID 



ptcroyltriglutamic ucid is increased by the addition of 5-pyridoxic acid 

 (2-methyl-3-hy(li()xy-4-hydi-oxym(;thyl-5-cai-hoxypyndiiie) or 4-pyridoxic 

 acid (2-methyl-3-hydroxy-4-carboxy-5-hydroxymethylpyridine). This sup- 

 plementary effect has been observed both for growth and hemoglobin 

 formation in the young chick''- and for regeneration of hemoglobin in hens 

 rendered anemic by bleeding.*^ 



Jukes and Stokstad'*^ failed to observe any effect of the pyridoxic acids 

 in increasing the effectiveness of pteroyltriglutamic acid. In a similar way 

 pteroylheptaglutamic acid was found by Binkley et al}^ to be as effective 

 on a molar basis as • the monoglutamate without the addition of pyridoxic 

 acid. 



c. Requirements of Turkeys and Ducks 



Richardson et al}^ reported that a deficiency of this factor in the diet of 

 the turkey produces cervical paralysis (Fig. 11) in addition to a reduction 

 in growth rate. No marked anemia was observed. Cervical paralysis was 

 also observed on a practical diet containing corn, wheat bran, and wheat 

 middlings, which indicates that a deficiency of PGA can occur on diets 

 composed primarily of natural ingredients. Spontaneous remissions of cervi- 

 cal lesions were not observed. Complete recovery was obtained in 4 to 6 

 hours by injection of 100 y of PGA. Thus far cervical paralysis has not been 

 reported in chicks deficient in PGA. Jukes et al}"^ found the requirement 

 of this factor for maximum growth of the turkey to be approximately 1.0 

 mg. per kilogram of diet. 



Although large variations exist, the PGA requirement of the turkey for 

 growth appears to be higher than that of the chick. Schweigerf** reported 

 PGA and pteroyltriglutamic acid to be equally effective in increasing PGA 

 blood levels and preventing the symptoms of mild anemia to severe ane- 

 mia, poor feather condition, and weakened legs. After 8 weeks of the un- 

 supplemented diet, the hematocrit had dropped to 28 %, compared to 40 % 

 for those receiving 2 mg. of PGA per kilogram of diet. Curative treatment 

 with the vitamin increased the hematocrit to normal in 2 weeks. 



DvK^ks grown on a purified type of diet give a marked growth response 

 to the addition of 100 7 per day of pteroyltriglutamic acid."*^ 



"^ M. L. Scott, L. C. Norris, and G. F. Ileuser, Science 103, 803 (1946). 

 ^^ T. H. Jukes and E. L. R. Stokstad, J. Biol. Chem. 168, 563 (1947). 

 ^6 S. B. Binkley, O. D. Bird, K. S. Bloom, R. A. Brown, D. G. Calkins, C. J. Camp- 

 bell, A. D. Emmett, and J. J. Pfiffner, Science 100, 36 (1944). 

 "'■' L. R. Richardson, A. G. Ilogan, and H. L. Kempster, J . Nutrition 30, 151 (1945). 

 " T. H. Jukes, E. L. R. Stokstad, and M. Belt, J. Nutrition 33, 1 (1947). 

 "8 B. S. Schweigert, Arch. Biochem. 20, 41 (1949). 

 "» D. M. Hegstod and F. J. Stare, J. Nutrition 30, 37 (1945). 



