Unrecognized mineral status insufficiency (subclinical deficiency) is difficult to detect. Figure 1 (click to enlarge) depicts the effects of trace mineral deficiencies in cows and calves. A mineral deficiency first impacts the immune system. Subtle effects on immunity often go undetected. Slow growth rate and/or poor reproductive performance may also be a result of insufficient mineral intake. Because health challenges and poor performance can be influenced by many factors, the mineral status of a herd may often be overlooked.
Efficiency of production continues to be lost when mineral insufficiency goes uncorrected. Mineral deficiency manifested by clinical symptoms is usually critical. The most commonly recognized mineral deficiency is hypomagnesium, which effects cattle grazing low magnesium forage (such as stockers on wheat pasture). Most mineral insufficiencies are typically subclinical, meaning producers won't see obvious signs. What occurs is production on a level below what could be obtained with optimum mineral nutrition.