There is a great deal of pressure when trying to finish lambs for sale and there are numerous factors which can result in delays. Trace element status of growing lambs is an aspect which should not be overlooked as deficiencies and toxicities will lead to reduced productivity.
Did you know that an adequate supply of cobalt is critical for lamb growth? After cobalt is consumed by the lamb, it reaches the rumen where bacteria utilise the cobalt to produce Vitamin B12. This Vitamin B12 is integral to glucose synthesis and thus impacts on how the lamb utilises its food (as such the food conversion ratio of that animal.)
Ruminants have no capacity to store cobalt and as a result lambs are very susceptible to Vitamin B12 deficiency. This is also known as “pine” and can result in poor growth rates. In order to tackle a cobalt deficiency a continuous supply of cobalt must be utilised (such as a bolus).
Selenium is required to produce proteins which are integral to the innate and adaptive immune system. Therefore Selenium plays an important role in disease defence. A relationship exists between selenium and iodine and so they must always be considered together when investigating suspected deficiencies.
Iodine is integral to the thyroid hormones T3 and T4. The thyroid hormones regulate the rate of metabolism and control the rate of absorption of carbohydrate from the gastrointestinal tract. This rate is important in achieving a good food conversion ratio. In lambs, for the inactive T4 to be converted into an active T3, an enzyme which contains selenium must be present.
Copper is a component of enzymes which are important for energy metabolism. It is very important to remember that copper can be toxic to sheep and so copper supplements should only be given if a deficiency has been diagnosed. Blue faced Leicester and Texel sheep are particularly susceptible to copper toxicity.
What approach should I take in my flock?
Forage is incredibly variable not only between fields on the same farm, but from year to year. You must also take into account any other supplementation given such as concentrates, lick buckets, drenches etc and you can begin to see that it’s impossible to take a ‘one shoe fits all’ approach between different management systems.
You should work with your vet to determine which, if any, trace element imbalances are present within your livestock. This is very important because there is no benefit to giving trace element supplementation if no deficiencies exist. Indeed, it may even harm the lambs as copper and selenium can be toxic if over supplied.
From a commercial aspect there are two main considerations which justify the importance of investigation:
- You could be spending money on trace elements which are not required.
- You could be losing animal productivity to sub-clinical disease. Sub-clinical trace element deficiencies are not severe enough to be visualised by eye but will have an impact on the productivity of the animals. If you wait until the deficiency is so severe that clinical signs have appeared you will already be out of pocket.
Sheep, Blue faced Leicesters and Texels in particular, are susceptible to copper toxicity. Selenium may also be toxic if over supplied. Please consult a vet or nutritionist to establish the need prior to supplementation.