The Use of an Animal Protein Factor Supplement in a Practical Poultry Ration

Abstract

IT HAS been demonstrated that fishmeal is a good source of vitamin B12, and possibly one or more unidentified growth factors for the chick (Brant and Carver 1947, Carlson et al., 1949, Combs, et al., 1948, Heuser et al., 1946, Hill 1948, McGinnis and Carver 1947, Weise et al., 1948, Weise et al., 1949). It is possible, therefore, that in many practical diets for chicks the peculiar value of fishmeal may lie chiefly in its contribution of these factors rather than its contribution of indispensable amino acids.Relatively inexpensive sources of vitamin B12 are now available commercially in the form of concentrates prepared as fermentation by-products in the production of antibiotics. These concentrates have been suggested as a total or partial replacement for fishmeal and certain other protein supplements in poultry diets. Indeed several papers have already appeared describing investigations of this kind (Briggs et al., 1949, Lindstrom et al., 1949, Weise et .