A Comparison of B12, Fish Solubles and Whey in the Growth of Chicks

SINCE the discovery of vitamin B12 there have been numerous reports concerning the presence of additional factors required by chicks for maximum growth. Menge, Combs and Shorb (1949) showed that liver products and dried whey contained an unidentified growth factor required by chicks fed a purified diet. Subsquently, Combs et al. (1950) using a practical type of ration presented evidence of two unidentified factors in liver. Chicks responded significantly to levels of liver paste dialysate, containing either of these factors, which supplied unappreciable amounts of vitamin B12. Menge, Combs and Hsu (1951) described the response of chicks and poults to two separate unidentified factors, one of which was contained in certain liver preparations and dried brewers’ yeast, and the other in dried whey. A description of some physical and chemical properties of the liver factor indicated its nonidentity with vitamin B12. Reed et al. (1951) reported that dried whey improved . . .