While sheep are copper sensitive, goats can tolerate more copper than sheep and appear to need as much copper as cattle. The exception may be Angora and Pygmy goats. The exact amount of copper required in the goat's diet is currently unknown and is dependent upon several factors. However, the goat needs far more dietary copper than was originally thought. Testing can reveal enough copper in tissue or blood samples and the goat can still be copper deficient. This is due to the complex interaction of minerals in the goat's metabolic system. Copper is essential in the proper development of the central nervous system, correct bone growth, and hair pigmentation. Copper-deficient goats have difficulty conceiving kids and, if bred, abortions are not uncommon. Copper supplementation can sometimes help but cannot always eliminate these health problems.
Copper deficiency can be the result of low levels of the mineral in the soil and in forages raised on the soil; this is primary copper deficiency. However, both the feed and the soil can have adequate copper but its absorption can be interfered with by minerals known as copper antagonists: lead, iron, manganese, various sulfates, cadmium, and molybdenum. This is secondary copper deficiency.
Here are some resources:
Dairy Goat Journal, Copper's Role in Goat Health
eXtension, Goat Nutrition, Copper