Dec 17, 2020
Take timely steps to tackle selenium deficiency in ewes and lambs
Dec 17, 2020
As seen in NSA Sheep Farmer December 2020
As we approach lambing season, now is a crucial time to prioritise ewe health and nutrition to prevent a selenium deficiency from occurring down the line.
With this having a severe impact on both ewes and lambs, Anwen Jones, Wales regional business manager at Lallemand Animal Nutrition, provides guidance on managing selenium levels for farmers across the country.
Impact of selenium deficiency on lambs
Selenium is an essential trace mineral for animal life that’s required to maintain normal physiological functions and as a component of antioxidants which help build immune defences.
“In sheep, just as with humans selenium deficiency typically presents as issues with movement. This is because low selenium levels affect oxygen supply to the muscles making them less elastic, and weaker. So, your ewes are going to have birthing problems and your lambs are going to struggle if you don’t have enough available selenium in your soil and animal feed,” explains Mrs Jones.
Although selenium deficiency affects the growing foetus and can cause birth defects, often the first indication that there is a problem is at the onset of lambing. Selenium deficient lambs are weak, and their muscle tone can be described as flaccid, so birth presentation can be poor.
“You’ll see the ewe straining but only fluid gushing out. These weakened lambs don’t move into the right position. Instead, they are more likely to present in the birth canal in the breech position or with a head or a leg turned back. Or worse, fail to move into the birth canal at the appropriate time altogether,” she explains.
After birth, lambs may also suffer from white muscle disease. This is a degeneration of the skeletal and cardiac muscles of lambs, which can lead to paralysis. Affected lambs may die from starvation or exposure and are more susceptible to scours and pneumonia.
“Low selenium levels increase the risk of white muscle disease and lamb mortality, so it’s very important to ensure the ewe’s diet is balanced for adequate mineral supply in the run-up to lambing,” she explains.
Treatment for selenium deficiency
Before treating flocks for a selenium deficiency, Mrs Jones stresses it is important to be clear of the diagnosis, as several different diseases can have similar symptoms to selenium deficiency, and an excess of the element can be toxic.
“Accurate diagnosis often requires blood samples, so it is best to speak to your vet before embarking on treatment plans,” she notes.
“There are a number of different treatment options available, and your vet will be able to advise on the most appropriate method for your system, but injection is often used to quickly restore selenium levels in sheep.”
How to prevent a selenium deficiency
“Pre-lambing forage should be carefully analysed to decipher it’s nutrient and mineral content, as this will enable producers to determine whether mineral supplementation is required. Geographical location can also impact selenium levels, so testing grazed fields, and carrying out a forage analysis when buying in fodder from other areas is really important.
“Be aware that feeding treated home-grown cereals and grain, and root crops, all have the potential to cause incorrectly mineralised rations, with certain root crops known to be low in both selenium and vitamin E,” she says.
If farmers identify that the diet and soils may be low in selenium, an approved organic selenium such as Alkosel R397 can be added to the diet.
“This supplementation will increase the absorption of selenium by the foetus via the placenta helping ensure the delivery of healthy viable lambs, as well as increase selenium concentration levels in colostrum and early milk,” adds Mrs Jones.
For more information on Alkosel a premium source
of bioavailable selenium click here