Trace Elements and Minerals

Written by Bas van Luijk - Veterinarian, East Coast Farm Vets

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As we prepare for the winter months, ensuring animals receive the right balance of trace elements is crucial for maintaining health and productivity.

The key elements of selenium, copper, cobalt and iodine, are known to be deficient in many soils and can cause real problems if not addressed. New Zealand soils are also low in zinc, but less so.

Trace elements are a group of 15 elements, essential for the health and productivity of all animals.

Adequate daily intake of these key elements is required for maintaining an efficient metabolism, resistance to disease, good liver function, healthy growth, good reproduction and efficient feed conversion.

Selenium deficiency is commonly associated with poor growth and infertility in spite of good feeding levels and can contribute to a weakened immune system. A deficiency of selenium can also result in a higher incidence of retained foetal membranes and an increase in mastitis.

Copper deficiency in livestock can be primary (low dietary copper levels) or secondary. A secondary deficiency occurs when an interaction between copper and other elements reduces the availability and absorption of copper from the diet.

Typically, copper deficiency results in a combination of symptoms including, intermittent scouring and light tinge to the coat, especially around the eyes, high empty rate in cows and weak bones in growing animals.

Iodine – the role of iodine in mammals is the formation of the thyroid hormones. These hormones have a significant impact on the growth and development of the foetus, and protein and energy production in general.

Symptoms in the new born animals can include an enlarged thyroid gland (goitre), blindness, hairlessness and the birth of weak or stillborn calves and lambs. In older stock deficiency can result in depressed wool and milk production, suppressed heats and poor reproductive performances.

Cobalt in ruminants is required for the production of Vitamin B12. Vitamin B12 is formed in the rumen by micro-organisms. There is no significant storage of cobalt within the animal so requirements have to be met by daily intake. Once Vitamin B12 is produced, it can be stored in the liver and takes on the main role in energy and amino-acid metabolism supporting good growth rates and milk production and a reduction of anaemia and scouring.

Zinc – the role of Zinc in protecting stock from facial eczema is well known. As there is no significant store of zinc in the body, requirements have to be met by daily intake. Pasture levels can vary considerably across regions but are generally considered to reach minimum requirements provided stock is fed well.

An acute shortage of any of these elements can lead to clinical disease. Symptoms can be subtle but significant production losses, poor health and animal stress can occur, leading to lower profitability. Talk to your vet team today about various ways you can help combat mineral deficiency.

This article was published in the Gisborne Herald on 17/05/25.