Summary and Implications
Supplementing the trace minerals copper (Cu), manganese (Mn), and zinc (Zn) in the metal hydroxyl form does not impact dry matter (DM) digestibility, while sulfatebound trace minerals decreased DM digestibility. Metal hydroxy trace minerals solubilize in the pH found in the abomasum, enabling absorption, suggesting that these minerals solubilize only in the abomasum and will not inhibit digestion. Trace minerals present in the basal diet prior to supplementation appear to be adequate for proper function of rumen microbes.
Iowa State University
Genther, Olivia N. and Hansen, Stephanie L.
"The Effect of Trace Mineral Source and Concentration on Mineral Solubility in the Rumen and Diet Digestibility,"
Animal Industry Report:
AS 659, ASL R2778.
Available at: http://lib.dr.iastate.edu/ans_air/vol659/iss1/29