TRACE MINERAL REQUIREMENTS OF GRAZING CATTLE

The following paper discusses the impact of four specific trace elemen ts-copper, zinc, selenium and manganese-on production and health param eters of grazing cattle. Typically in the cattle industry the greatest impairment of marginal trace element deficiencies may be on immune fu nction, but in cases of severe deficiencies production traits such as reproduction efficiency and other performance parameters can be impact ed. It is important that the diet formulation for trace minerals consi der the forage intake, the forage trace mineral content and the animal 's requirements and then dietary levels fed to meet animal requirement s just as is typically done for nutrients such as energy and protein. Although minerals and trace elements have not received the degree of a ttention that energy and protein have in formulating grazing cattle di ets, their potential impact on productivity should not be ignored.