Studies on Zinc in Poultry Nutrition: 1. The Effect of Feed, Water and Environment on Zinc Deficiency in Chicks

Abstract

O’DELL and Savage (1957a) recently described the production and symptoms of a zinc deficiency in the chick. They found that chicks kept under standard battery brooder conditions and fed a purified Drackett protein diet (analyzed to contain about 50 ppm. of zinc), showed deficiency symptoms characterized by a retardation in growth, a shortening and thickening of the long bones and a reduction in the ash content of the dry fat-free tibia. These symptoms were not observed when adequate zinc was fed in the diet. In another more detailed report, these workers (O’Dell and Savage, 1957b), obtained a growth response from zinc supplementation in five experiments. These results indicated that the Drackett protein diet used by a number of workers (Dannenburg et al., 1955; Morrison et al., 1955) for studying unidentified minerals may be deficient in zinc even though 6–7 ppm. of zinc is supplied by the mineral mixture. Since . . .