Copper dietary supplement. Copper is an important dietary element. Among other things, it aids iron absorption, boosts enzymes involved in development of connective tissues such as cartilage, tendons and ligaments, and is one of the key minerals for healthy hoof development. Copper deficiency can result in abnormal bone development and osteoporosis. It is also essential to the blood coagulation process. Early signs of copper deficiency: Dull, discoloured coat with a "mangy" appearance, sometimes with a reddish tinge. Brown or white hairs around the eyes creating a bespectacled appearance. Poor performance related to low red blood cell count or recurring anaemia. Feed: 30 ml daily in feed. Cuppra can also be added to grazing horses' drinking water. Do not give copper supplements for more than 30 days at a time. 1 l.