Availability of Zinc from Metallic Zinc Dust for Young Swine

Abstract

Measures of growth and serum Zn concentration were made on young growing pigs receiving a low Zn (20 ppm) basal diet supplemented with 25 or 50 ppm of Zn from either zinc oxide or metallic Zn dust from the metal smelting and refining industry. Growth was not sensitive to either source or level of supplemental Zn, but serum Zn concentration increased linearly with increases in supplemental dietary Zn from either source. Equations for the linear regression of serum Zn concentration on supplemental dietary Zn were calculated from the data on blood samples after 2 and 5 weeks of the trial. The ratio of the slope of the regression line for metallic Zn dust to that for zinc oxide was 1.30 and 1.33 for the 2-week and the 5-week data, respectively. The availability of Zn from this metallic Zn dust to young growing pigs was therefore estimated to be about 30% greater than that from zinc oxide powder.