Essential trace element with multiple functions. It forms part of several enzyme systems responsible for maintaining elastic connective tissues and cartilage, the antioxidant neutralization of free radicals & ROS, preservation of healthy mitochondria, formation of haemoglobin and production of the pigment melanin. Some 66% of total body copper is found in muscle and 20% in bone with significant amounts also present in blood and the liver where it is stored.
Copper is found in forages and grains and often fortified in manufactured feeds. Total tract digestibility of ingested copper is around 40% and may be reduced by competition with Zinc and Cadmium by competition for binding sites in the gut wall. Once absorbed copper passes to the liver where it may be stored prior to use. Copper stores in the liver are laid down by the foetus and carry the newborn foal through the first few weeks of life, so copper status of the pregnant mare is important.
The developmental bone disease Osteochondrosis OCD in foals has been associated with low copper levels in several studies. Whether OCD is actually due to a copper deficiency or whether it can be prevented by raising copper supply above a basic level remains unclear. However, despite copper fortification of stud feeds becoming standard practice for more than a decade, the rate of OCD on Australian and overseas thoroughbred stud farms has remained stubbornly high, so copper is only a part of that complex story.