Pasture forage is the most significant contributor to the trace mineral nutrition of grazing beef cattle. Mineral supplementation in beef cattle can be divided into two broad categories, macro-minerals and micro-minerals. These categories are based on the amount of mineral required in the cow’s diet. As a rule of thumb, micro-minerals are required in amounts less than 1 gram per day compared to macro- minerals, which are often required at levels greater than 1 gram per head per day.
While supplemental energy and protein may not be needed, it is generally recommended to provide supplemental minerals and vitamins. They have less impact than protein and energy on cow/calf performance and economics, but they should not be overlooked. While supplementation is important, over supplementation of minerals should be avoided to prevent possible environmental problems associated with runoff from waste or application of cattle waste to soil (e.g. phosphorus). Certain minerals can actually be toxic if supplemented in excessive amounts.
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