NADIS (National Animal Disease Information Service) is a network of 40 veterinary practices and 6 veterinary colleges monitoring diseases in cattle, sheep and pigs in the UK. NADIS is sponsored by Milk Development Council, the Meat and Livestock Commission, Elanco Animal Health and Intervet.

According to NADIS data, copper deficiency is one of the most commonly recorded mineral deficiencies. Because copper is involved in a wide range of systems within the body, copper deficiency produces a wide range of problems.

Adult cattle deficiency has been linked to mastitis, reduced yield and condition, infertility, abortion, coat depigmentation and scouring; in younger animals the list includes poor growth, scouring, stiffness, brittle bones and hair depigmentation

The young calf usually has a good liver reserve of copper when it's born, and before the rumen develops it is up to 40 times better at absorbing copper. Most copper problems occur in calves 3 months+ of age, at grass, or sucking their mothers.

Copper deficiency is either primary, which occurs because the animal gets too little copper, or secondary, when other minerals, particularly molybdenum, reduce the availability of copper.

Because it is common, a range of copper products are available to treat or prevent copper deficiency. However, copper supplementation costs money, so it's important to ensure that you do need copper.

Tests available

A large number of tests are available, but none foolproof.

Copper in the feed

Before supplementing copper it is a good idea to get an estimate of how much copper your animals are getting in their feed. However measuring copper alone is not enough, you also need to measure iron, sulphur and molybdenum intake too. It is also important to measure sulphur and iron in the drinking water too.

Blood tests

Blood test for copper are widely used, however they suffer from the problem that blood copper levels fall only at the end of the process as they are kept high by release of copper from the liver. Thus animals with apparently normal blood copper can be deficient.

Liver biopsy

Copper is stored in the liver. Animals on copper-deficient diets lose copper gradually from their liver. Thus liver copper gives a good guide to copper status. It is not foolproof though; liver copper can be significantly reduced by high iron intakes without the animals showing signs of copper deficiency. This is where interpretation comes in. If you have low liver copper, no signs and high iron intakes, supplementing copper may be an expensive luxury.

Liver biopsy is the best method of collecting liver samples for copper measurement, as the liver copper of the affected group can be directly measured, rather than relying on measurements in culled cows or other casualty animals.

Testing the response to supplementation

In many cases the only conclusive test is to give the animals copper and measure the response.

The best way to do this is to identify a likely need for copper by testing and then to supplement a portion of your animals, leaving some untreated and compare the two groups.