90 KARL FOLKERS 



TABLE XXII 



Unidentified Growth Stimulant in Proteins for Rats 

 Growth response of rats to casein preparations (Womack and Rose, 1946) 



Number of Average total gain 



Supplement % animals in 28 days, grams 



There are numerous other investigations in progress on other factors. 

 A partial list of these other unidentified factors and vitamins is given 

 in Table XXIII. No doubt some of these nutritional studies are the 

 frontier investigations on new factors which will gain importance in 

 the future. 



TABLE XXIII 



Partial List of Other Unidentified Factors 



Growth factor for Clostridmm sporogenes Knight and Fildes (1933) 



Vitamin P (permeability vitamin) Rusznyak and Szent-Gyorgyi (1936) 



Factor for reproduction in chickens McGinnis, Heuser, and Norris (1944) 



Feeding factor for chicks Cravens, McGibbon, and Halpren (1944) 



Anemia and weight factors for the pigeon Street (1944) 



Chromotrichia factor (s) for the dog Frost and Dann (1944) 



Unrecognized vitamins for the pig McRoberts and Hogan (1944) 



Liver factor (s) for sulfapyridine anorexia 

 in rats and dogs Handler (1944) 



Factor for growth of Tetrahymena geleii Kidder and Dewey (1944) 



Growth factor for Clostridium perfringcns Ballentine and associates (1944) 



Growth factor for guinea pigs Woolley and Sprince (1945) 



Unidentified factor essential for rat growth. Hartman (1946) 



Chick growth factor occurring in cow 

 manure Rubin and Bird (1946) 



Growth factor for Lactobacillus gayoni 

 8289 Cheldelin and Riggs C1946) 



