RESPONSE FROM COPPER AND SELENIUM WITH VITAMIN E INJECTIONS TO CATTLE PASTURED ON MINERAL AND ORGANIC GROUNDWATER SOILS

Abstract

An experiment, using a total of 127 cattle on one ranch over a 2-yr period and 82 cattle at two separate locations on a second ranch in 1 yr, tested injections of copper (Cu) and injections of selenium (Se) with vitamin E, separately and in combination. Injections of 100 mg Cu as copper calcium edetate resulted in an increased overall daily gain of 118 g or 22%. The injections of Se and vitamin E did not significantly increase gain and there was no synergistic effect when the two materials were given together. The crude protein, inorganic sulfate, S, P, Ca, K, Mg, Cu, Mo, Fe, Mn, Zn, and B concentrations were determined on grass from the experimental pastures and from grass growing in fields around one ranch. These latter forages were collected in seven paired locations with one member forage of each set being harvested from an organic groundwater soil and the other from an adjacent clay soil where there was good drainage. Forage growing on well-drained soils had a Cu/Mo ratio of 1.9, which was almost treble the 0.7 ratio found in forage grown on the groundwater soil. Cu levels in hair from cattle on ranch B, given only Cu injections, averaged 13.4 ppm Cu on an oven-dry weight basis, which was 54% higher in Cu than hair from the control cattle. The mean concentration of Se in hair of cattle receiving Se with vitamin E was 60 ppm, which was not significantly different from the control at 58 ppm.