Unidentified Growth Factors Required by Chicks and Poults

FOLLOWING the work of Menge et al. (1949), which showed that chicks require an unidentified growth factor in addition to vitamin B12 and other known nutrients, numerous similar observations have been reported. Most of these have been reviewed by Combs (1951), Menge et al. (1952), Briggs (1952) and Branion and Hill (1953). In a preliminary report, Arscott and Combs (1950) presented results which indicated that chicks fed a corn-soybean oil meal type ration responded to two different growth factors. One factor was present in fish meal; the other was supplied by butyl molasses fermentation solubles. Kohler and Graham (1951), and Couch et al. (1952) with chicks and Scott and Jensen (1952) with poults, have obtained similar evidence for two distinct factors. It also has been noted that certain orally administered antibiotics appear to spare the dietary requirement of the chick for unidentified growth factors (Groschke, 1950; Jones and Combs, 1951; …