Ruminant Nutrition: Beef: Vitamins and Minerals

Trace minerals have long been identified as essential dietary components for domestic livestock species. Included in the category of essential trace minerals (or microminerals) are chromium, cobalt, copper, iodine, iron, manganese, molybdenum, nickel, selenium, and zinc. Numerous biochemical reactions require trace minerals for proper function. It has been well documented that deficiencies of various trace minerals can result in metabolic diseases. The interactions between trace minerals and metabolic processes are extremely complex. Trace minerals have been identified as essential components for carbohydrate, lipid, protein, and vitamin metabolism, and have been shown to be involved in hormone production, immunity, and cellular homeostasis. Past and current research would suggest that copper (Cu) is involved in lipid metabolism in ruminants. Copper supplemented at physiological concentrations to beef cattle has been reported to be involved in cholesterol metabolism, ruminal biohydrogenation, catecholamine production, and lipid metabolism of subcutaneous adipose tissue. Additional impacts of Cu on lipid metabolism and homeostatic mechanisms related to Cu metabolism are currently being investigated. Recently, we have reported that genes involved in bovine liver Cu homeostasis, ATP7A, ATP7B and Cox17, are correlated with CTR1 gene expression in the bovine liver, similar to those reported for non-ruminants. Despite the apparent involvement of certain trace minerals in animal production and disease resistance, deficiencies of trace minerals have not always increased the susceptibility of domesticated livestock species to natural or experimentally induced infections or decreased performance. There are many factors that could affect an animal’s response to trace mineral supplementation such as the duration, concentration, and source of trace mineral supplementation, physiological status of an animal (i.e., pregnant vs. non pregnant), the absence or presence of dietary antagonists, environmental factors, and the influence of stress on trace mineral metabolism.