Zinc Requirement of the Chick: Factors Affecting Requirement

EARLY experiments by Titus (1932), Insko, Lyons and Martin (1938) and Lyons, Insko and Martin (1938) failed to show zinc to be a dietary essential for the chick. More recently, Mehring, Brumbaugh and Titus (1956) observed no beneficial effect upon growth of chicks from increasing the amount of zinc consumed from 42 to 820 mg. of zinc per kg. of diet. In studies on perosis, Wilgus, Norris and Heuser (1937), found that zinc as well as manganese had a beneficial effect upon the incidence of perosis, but under the conditions of their experiments manganese was shown to be the primary deficiency. Therefore, it was not until 1957, as a result of studies by O’Dell and Savage, that a true zinc deficiency was recognized in the chick. Edwards, Young and Gillis (1958), Moeller and Scott (1958), Morrison and Sarett (1958), Patrick (1958), and Roberson and Schaible (1958) have confirmed the original…