How do we tackle copper deficiency?

Cows with "glasses" and stiff, spiky coats, with the appearance of unthriving.

We have been receiving more and more enquiries concerning copper deficiency from consultants and farmers recently. Cows develop "glasses" (rings around their eyes) and stiff, spiky coats, with the appearance of unthriving. Whether this is due to more focus on the problem or an actual feed-related problem is difficult to say.

The norm for copper is 10 mg per kg DM, or approx. 250 mg copper in total. The natural content of the feed typically contributes 100-150 mg, to which the mineral feed adds the remainder, at least 150 mg. Copper in the feed is dissolved in the digestive system under the influence of chewing, pH and microbes. Cu-metal ions are then absorbed in the digestive tract either directly or via microorganisms. Copper is found in biochemical processes and in enzymes, and contributes to the synthesis of:

  • Haemoglobin (the protein that transports oxygen from the lungs to tissue)
  • Keratin (the main component in horns and hair)
  • Melanin (protective pigment/solar filter)

Copper easily interacts with molybdenum, sulphur and iron, and forms inaccessible Cu complexes. Only a very small amount of copper is absorbed in the upper small intestine, usually less than 10%, before being deposited in the liver, which contains 10-50 mg of copper. The sulphur content in rations with large amounts of rapeseed cake/crushed corn (NON-GM) is high, with the inherent risk of formation of Cu complex.

The molybdenum and iron content in the roughage depend on where the roughage was harvested. Copper sulphate, organic-bound copper (glycine-bound) and dicopper chloride trihydroxide can be added to the mineral feed. We recommend using easily-digestible copper sources along with mineral analyses of the roughage if there are signs of copper deficiency.


If you have any questions concerning copper deficiency in your herd - contact your cattle consultant at Vilomix here