296 PYRIDOXINE AND RELATED COMPOUNDS 



mice deficient in vitamin Be, but not as much as casein of equivalent trypto- 

 phan content; amino acids other than tryptophan also appear to be in- 

 volved. 



The growth rate and survival time of weanling mice receiving 2 7 or 

 more of pyridoxine per gram of food are unaffected by variations of 10 to 

 60 % in dietary casein. Pyridoxamine and pyridoxal are less active for mice 

 than pyridoxine, especially on high casein diets. ^^ 



When adult white mice are given a medium dose of x-rays (350 r. in a 

 single exposure), they succumb within a shoit time. The survival time can 

 be prolonged by the daily injection of 50 7 of pyridoxine for 7 days preced- 

 ing and 13 days after irradiation. ^^ 



3. Hamsters 



The vitamin Be requirement of the hamster has not been adequately es- 

 tablished. Schwartzman and Strauss^" have sho^vn that the daily subcutan- 

 eous injection of 50 7 of pyridoxine was sufficient for good gro'svth. As in 

 rats, the inclusion of corn oil in the diet of vitamin Be-deficient hamsters 

 delayed the onset of the deficiency symptoms; fat appeared to have a spar- 

 ing action. 



Unpublished data by Fisk-^ suggest that the male hamster requires 800 

 7 of pyridoxine per 100 g. of diet, whereas the female hamster requires 400 

 7 per 100 g. of diet. 



The hamster's reciuirement for vitamin Be appears to be the highest of 

 all rodents studied thus far. 



4. Dogs 



No reliable data are available for the vitamin Be requirement of the dog. 



5. Pigs 



Although the precise requirement is not known, 200 7 of pyridoxine per 

 kilogram of body weight permits the pig to grow normally and prevents the 

 development of anemia.-^ Corn oil does not spare pyridoxine in curing ane- 

 mia. 



6. Monkeys 



No quantitative data are available for the monkey's vitamin Be require- 

 ment. However, it has been observed that monkeys receiving 1 mg. of pyri- 



18 E. C. Miller and C. A. Baumann, J. Biol. Chem. 159, 173 (1945). 



19 A. Goldfeder, L. Cohen, C. Miller, and M. Singer, Froc. Soc. Expll. Biol. Mcil. 67, 

 272 (1948). 



20 G. Schwartzman and L. Strauss, /. Nutrition 38, 131 (1949). 



21 W. W. Fisk, B. S. Thesis, Massachusetts Institute of Technology, 1951. 



22 G. E. Cartwright, M. M. Wintrohe, and S. Humphreys, J. Biol. Chem. 153, 171 

 (1944). 



