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Department of Poultry Husbandry, Cornell University, Ithaca
Evidence has been presented which shows that dried pork liver contains a factor required to prevent the development of a pellagra-like syndrome in chicks fed an egg-white diet and a factor required for the growth of chicks fed a purified-casein diet. This growth-promoting factor was soluble in an alcoholwater solution, was stable to heating in a dry atmosphere and relatively stable to autoclaving at pH 11. On the other hand, the pellagra-preventing factor was insoluble in an alcohol-water solution, was destroyed by heating in a dry atmosphere and by autoclaving at pH 11 but not at pH 9. This demonstrates that the pellagra-preventing factor is separate from the growth-promoting factor. The growth-promoting factor is vitamin G.
Evidence has also been presented which strongly indicates that the pellagra-like syndrome which develops in chicks fed the egg-white diet is identical with that which develops to a lesser extent in chicks fed the purified casein diet.
When egg white was autoclaved for 6 hours at 15 pounds pressure at pH 5.9 to 6.0 or pH 9, it no longer caused the development of the pellagra-like syndrome. It is believed the more probable explanation of this is that the pellagra-preventing factor is formed or released during autoclaving rather than that a toxic factor is destroyed, in view of the apparent identity of the pellagra-like syndromes and since raw egg white is almost the only source of protein used by the developing chick embryo.
2 A. T. Ringrose is now affiliated with the Nutritional Laboratory, National Oil Products Company, Harrison, N.J.
Manuscript received 1 July 1936.