Copper
Copper is an important component of many enzymes and participates in iron absorption and synthesis of hemoglobin. Copper is found in grains and oilseeds probably at adequate quantities to meet the requirements, but determination of copper requirements of pigs is scarce. Copper deficiency signs include anemia and low growth rate. Copper toxicity occurs at levels above 250 ppm when fed for a long period of time (NRC, 2012).
Pharmacological levels of dietary copper (Feed Additives in Swine Diets – Pharmacological Levels of Zinc and Copper) between 125 and 250 ppm is commonly used in the diet to enhance fecal consistency in nursery pigs and improve growth performance in both nursery and grow-finish pigs (Bikker et al., 2016; Coble et al., 2017). The most commonly used source of dietary copper is copper sulfate (CuSO4) (Cromwell et al., 1998). However, tribasic copper chloride (TBCC) is as effective in promoting growth performance (Cromwell et al., 1998; Coble et al., 2017), while organic sources of copper such as Cu-Met chelate seem to have the potential to influence growth performance as well (Carpenter et al., 2018).