Effective Magnesium Supplementation at Turnout Crucial

Effective Magnesium Supplementation at Turnout Crucial

Friday, March 27, 2009

Steadily rising pasture potash levels in spring grass year on year are likely to be depressing magnesium availability in the rumen, warns Rumenco technical manager David Thornton 

"Analysis of average potassium levels in spring grass reveals an upward trend, from 2.63%K in 2006, to 2.72% in 2007 and 2.85% in 2008. This is probably due to increased slurry applications rather than any extra usage of potash fertilisers, but the danger of magnesium 'lock up' and threat of grass staggers is very real this year," he says. 

This means livestock farmers must put even more of an emphasis on highly effective magnesium supplementation around turnout this spring, particularly for lactating dairy cows and ewes. 

"The dairy cow requirement for potassium is only 1-1.4% of dry matter intake, so the levels in grazing alone far exceed this need even before any other dietary ingredients are included." 

However, David Thornton points out that the negative effects of high potassium levels can be offset by increasing sodium intake. Extra sodium in the diet helps improve magnesium absorption in the animal. 

"For the first six weeks post turnout it's crucial that your magnesium supplement includes extra sodium. It is for this reason that Supalyx Magnesium contains 4.5% sodium (equivalent to 11.2% salt), as well as 15% magnesium," he explains. 

"Suckler cows are particularly at risk at grass this spring because in most situations they do not receive any additional feed."

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