There is a great deal to consider in preparation for tupping with the subject of minerals and supplementation often arising, but do you understand what your flock actually requires?

Often we cannot rely on grazing alone to meet the daily requirements for the key trace elements. However which trace elements need to be provided by supplementation will depend on your grazing management and location.

By providing the necessary minerals to prevent deficiencies, and avoiding those which are already sufficiently supplied in the diet, we can optimise productivity and avoid toxicities.

The simplest way to determine your flock’s current trace element status is to ask your vet to perform a mineral audit which will likely consist of blood sampling, forage analysis, a review of dietary inputs and potentially testing liver samples.

If any imbalances are detected which must be rectified before tupping, action needs to be taken at least four weeks before the tup is introduced.

Therefore, it is recommended to carry out a mineral audit 6-8 weeks ahead of tupping to allow sufficient time for results to be received and plans to be implemented.

If you are reading this, and that window of opportunity has passed, it is never too late to act, and a mineral audit can still be performed at any time, yielding benefits.

So what are the key trace element imbalances?

Copper

Copper is utilised in enzymes responsible for thrive and fertility, for production of healthy wool, and for white blood cell function. White blood cell function is vital for immunity.

During gestation the ewe requires copper to develop the lamb’s nervous system. Without an adequate source of copper mid-pregnancy, the lamb’s nervous system is not formed correctly. This is known as swayback and cannot be treated.

Copper should never be supplemented to sheep without first consulting a vet or nutritionist to establish that there is a need, as excess copper can result in copper toxicity which can prove fatal.

While copper deficiency can be caused by insufficient copper in the diet, this is actually relatively rare.

It is far more likely that sheep are ingesting high levels of other elements that antagonise or deplete dietary copper, causing secondary copper deficiency and potentially thiomolybdate toxicity.

This is often an issue on farms where high levels of molybdenum, sulphur and iron are ingested.

Cobalt

Cobalt is required by the rumen microbes for the production of Vitamin B12 which is important for energy utilisation and is critical for growth, particularly in lambs. The body has no capacity to store cobalt, therefore cobalt must be continuously supplied.

Selenium

Selenium is vital for muscle function and deficiency can result in white muscle disease in lambs. Selenium deficiency is also a cause of impaired fertility, impaired growth, poor hair and wool quality and reduced immunity. Care must be taken as excess selenium can result in toxicity and death.

Iodine

Like cobalt, iodine is a trace element that ruminants have no capacity to store and a continuous supply must therefore be available. Where the animal’s diet is unable to provide this, supplementation will be required.

Stock deficient in iodine may suffer from:

• Poor growth and weight loss

• Weak/stillborn offspring

• Reduced fertility

• Goitre (enlarged thyroid)

Furthermore, ewes will not be able to transfer sufficient amounts of the element to the unborn lamb. This can result in lambs being born weak or dead.

While iodine is critical, excess supplementation to ewes has been shown to reduce IgG (antibody) absorption in newborn lambs. This could lead to an increase in conditions such as watery mouth or joint ill and emphasises the importance of supplying only what is required.

Zinc

Zinc is another trace element which ruminants have little capacity to store and so, where a deficiency exists, a continuous source of zinc should be supplied.

Zinc is required for fertility, including sexual maturity and the onset of oestrus. It also plays an important role in immune function, udder health, skin health, hoof health and wound healing.

Which method of supplementation is right for my animals?

If your vet diagnoses a trace element deficiency and has advised you to supplement trace elements, you have a number of options including oral drenches, licks and blocks, injections, pasture dressing, water supplementation, in-feed supplementation and trace element boluses.

Different forms of supplementation offer different advantages and disadvantages.

Where trace element deficiencies exist, it is advisable to choose a method of supplementation which delivers trace elements in a continuous, controlled and consistent way, at levels that are consistent with the animals’ daily requirements.

Boluses provide a convenient and controlled method of trace element supplementation with no variable intakes and no guesswork.

This is particularly important for animals requiring iodine, cobalt and zinc which cannot be stored in the body and therefore a daily supply is required. Their long-lasting nature is convenient and reduces labour costs as regular bolusing is not required.

  • This editorial was provided by Bimeda, makers of Cosecure, CoseIcure and ZincoIsel sheep boluses.