A Copper-Molybdenum Complex: Its effects and movement in the piglet and sheep

Abstract

Experiments were conducted to study the in vivo availability and movement of copper of a copper-molybdenum (Cu-Mo) complex. In baby pigs fed the Cu-Mo complex as the only copper supplement, serum copper levels were similar to those in pigs fed copper sulfate. However, the pigs receiving the Cu-Mo complex showed an increase in ceruloplasmin activity which was no greater than that in pigs fed a diet without supplemental copper. Tissue molybdenum concentrations were higher in pigs fed the Cu-Mo complex than in pigs fed an equal amount of molybdenum as the sodium salt. Conversely, tissue copper levels in the pigs fed the Cu-Mo complex were generally lower than those in pigs fed either copper sulfate or copper citrate plus sodium molybdate in equivalent amounts. In sheep given an intravenous injection of the Cu-Mo complex made from ⁶⁴Cu and ⁹⁹Mo, the rates of removal from the blood of the copper and molybdenum were equal, and this rate was more rapid than the removal of molybdenum when ⁹⁹Mo was injected alone. Conversely, the rate of urinary excretion of molybdenum from the ⁶⁴Cu-⁹⁹Mo-injected sheep was slower than from the ⁹⁹Mo-injected animal. These results support the hypothesis that copper bound in a Cu-Mo complex is biologically unavailable and indicate that such a complex can exist in vivo.