Which minerals should I be concerned with to prevent grass tetany in my lactating beef cows?
A. The best way to prevent grass tetany is to feed free-choice a mixture of equal parts magnesium oxide: trace mineral salt and grain (corn, barley, etc) beginning two weeks before the cows are turned out to pasture. The disease is caused by excess potassium in the forage which prevents magnesium absorption. Magnesium oxide will provide the magnesium and the salt will increase the sodium:potassium ratio in the rumen which improves magnesium absorption.
