Minerals and dietary supplements are essential components of livestock nutrition that support bone development, enzyme function, immune response, and reproductive performance. Domestic livestock require macro-minerals including calcium, phosphorus, magnesium, potassium, sodium, chlorine, and sulfur in relatively large amounts. Trace minerals, including copper, zinc, selenium, manganese, iron, iodine, and cobalt, are required in smaller quantities but are equally critical to health. Hay and Forage alone may not supply adequate levels of all minerals, particularly selenium and copper, depending on soil composition in the region.
Calcium and phosphorus are the most abundant minerals in the body and must be supplied in a ratio of approximately 1.5 to 2 parts calcium to 1 part phosphorus for most livestock. Magnesium deficiency, most commonly seen as grass tetany in lactating cattle grazing lush spring Pasture Rotations, is prevented by supplementing magnesium oxide. Salt, a combination of sodium and chlorine, is the most commonly supplemented mineral and is typically offered free-choice in block or loose form.
Selenium deficiency is widespread in many regions and causes white muscle disease in lambs, calves, and kids. Injectable selenium and vitamin E preparations are used as a preventive measure. Copper deficiency affects cattle and sheep, though sheep are highly sensitive to copper toxicity, so species-specific supplements are essential. Zinc supports hoof health, immune function, and skin integrity. Iodine is necessary for thyroid function and is commonly supplemented in iodized salt.
Minerals are offered in several forms: loose mineral mixes, compressed blocks, and molasses-based tubs. Loose minerals allow more precise consumption and are generally preferred, though blocks reduce waste from wind and rain. Medicated supplements containing ionophores or coccidiostats are available for specific management needs. Mineral consumption should be monitored, as overconsumption can cause toxicity and underconsumption leads to deficiency. Feed Rations should account for the mineral content of the base feed.
Mineral requirements vary by season, stage of production, and environmental conditions. Lactating animals have the highest mineral demands. Magnesium supplementation is critical during spring turnout on lush pasture. Selenium and vitamin E are particularly important before and after lambing or calving. Fresh water and free-choice mineral access should be available at all times.