IX. KFFKCTS OK DKFK I KNC Y 1// 



CoiupMiisoii of (lilTcrciil methods ot" ;uliniiiis(j-at ioir" showed lli;it suh- 

 cutMiu-ous injection was sHj^htly more crtcctixc than recdiiifi; l)y pipette. 

 In tiiitlier studies I'filVner el <il.''' fepoitcd that either I'd.V or its conjugate 

 at a le\('l of 0.25 m\i,. per kilogram of diet jj;ave maximum };i()\\ th hut sub- 

 maximal hemo.uloljin response. Brig<>;s and Liliie'""' luive shown that I m<;. 

 per kilogram of diet is necessary for normal feathor pifi;mentalion and 2 

 mii. for maximum <j;ro\vth. Oloson ct al}'' reported that PGA at a le\'el of 



1 to .") mji. per kiloj^ram of diet i>;a\i' normal growth and pigmentation of 

 feathers in chicks. The re(iuirem(Mit was not appreciably alter(>d by addition 

 of sulfamerazine or certain other intestinal antiseptics, 



Oleson cl o/.^"* found that the reciuirements for maximum growtii up to 

 f weeks were 0.4 mg. per kilogram of diet in one experiment and 1.0 mg. 

 in another. In both cases 1.0 mg. was required for optimum hemoglobin 

 response. Pteroyltriglutamic acid was found to be as effective on a molar 

 basis as the monoglutamate. The addition of 0.7 % of either sulfasuxidine, 

 sulfaguanidine, or carboxysulfathiazole did not affect the response on mar- 

 ginal \q\q\s of pteroyltriglutamic acid. Robertson et al ^^ found the require- 

 ments to be 0.-45 mg. per kilogram of diet for growth and hemoglobin up 

 to 4 weeks of age. The requirement at 6 weeks for optimum hemoglobin 

 was stated to be 0.35 mg. and 0.55 mg. for normal feathering. In these ex- 

 periments the PCt\ reouirements were not affected bj^ addition of 1 and 



2 % sulfasuxidine to a purified diet. It thus appears that sulfonamides do 

 not have as marked an effect on the PGA requirements in chicks as they 

 do in rats. 



Perosis has been observed by Hill et al}^ in chicks on a purified-type of 

 diet adequately substituted with choline, biotin, and manganese but de- 

 ficient in PGA. The incidence was increased by addition of 2 % sulfasuxi- 

 dine. The perosis was prevented by addition of 0.2 mg. per kilogram of PGA 

 without the sulfonamide and bj^ 0.3 mg. in the presence of the sulfonamide. 



Pteroyltriglutamic acid has been shown to be effective for the 

 chick.^' It has also been reported by Scott el al.*^ that the effectiveness of 



3' C. J. Camphcli, K. A. Brown, aiul A. I). Kmmett, J. Biol. Chcm. 154. 721 (1944). 



" J. J. PfifTner, D. G. Calkins, B. L. O'Dell, K. S. Bloom, 1{. A. Brown, i\ J. Camp- 

 bell, and O. D. Bird, Science 102, 228 (1945). 



■^« G. M. Briggs and R. J. Lillie, Federation Proc. 5, 124 (1946). 



" J. J. Oleson, B. L. Hutchings, and N. H. Sloane, ./. Biol. Chcm. 165, 371 (1946). 



»8 B. L. Hutchings, J. J. Oleson, and E. L. R. Stokstad, /. Biol. Chcm. 163, 447 (1946). 



'' H. I. Robertson, L. J. Daniel, F. A. Farmer, L. C. Norris, and (1. I', lleuser, 

 Proc. Soc. Expll. Biol. Med. 62, 97 (1946). 



'» F. W. Hill, L. C. Xorris, and G. F. Heuser, J. Nutrition 28, 175 (1944). 



" B. L. Hutchings, E. L. R. Stokstad, N. Bohonos, and \. H. Slobodkin, Science 99. 

 371 (1944). 



« M. L. Scott, L. C. Norris, G. F. Heuser, and W. F. Bruce, ./. Biol. Chcm. 158, 2'.)1 

 (1945). 



