Effect of dietary form of copper fed with or without added sulphur and molybdenum on the indicators of copper status and expression of copper transporters and chaperones in dairy cows

Dietary copper (Cu) is one of the most important trace elements for normal health and performance in dairy cattle (Suttle, 2010). Interactions between Cu, sulphur (S) and molybdenum (Mo) reduce Cu bioavailability either by the formation of insoluble thiomolybdates in the rumen or, in the absence of adequate Cu, are absorbed and bind to Cu present in biological compounds. Cellular Cu homeostasis is mediated by transporters and chaperones including COX17, CTR1 and ATP7B, although the effect of form of dietary Cu or the presence of Cu antagonists such as S and Mo on gene expression is unclear. The objectives of the current study were to determine the hepatic expression of key members of the copper transport system in response to inorganic or organic forms of dietary Cu in the presence or absence of added S or Mo.