One of the wettest starts to the year on record is raising fresh concerns about mineral deficiencies in grazing livestock this spring, with advisers warning farmers to assess trace element status carefully ahead of turnout.
Met Office data shows the UK as a whole recorded 17% more rainfall than the long-term meteorological average in January, with some regions experiencing near-record-breaking totals, such as Cornwall which has provisionally recorded its wettest January on record.
With soils saturated for prolonged periods, advisers warn that mineral leaching and reduced plant uptake could pose challenges at turnout.
Nia Williams, commercial and technical manager at Nettex, said prolonged waterlogging can significantly affect trace element availability.
“When soils sit wet for extended periods, oxygen levels are reduced and root function is compromised,” she explained. “This can limit mineral uptake by the plant. At the same time, we can see increased soil intake and therefore higher intakes of antagonists such as molybdenum and iron, which interfere with the absorption of key minerals like copper, manganese and zinc in the animal.”
Rapid grass growth later in the spring may also compound the issue, she added. “Fast-growing grass can dilute trace element and magnesium concentrations. Combined with low dry matter and high potassium and nitrogen levels, this increases the risk of deficiencies and conditions such as grass staggers,” said Mrs Williams.
Unlike some minerals, magnesium cannot be stored effectively in the body, meaning cattle require consistent daily intake during high-risk periods.
With many farms preparing for turnout, advisers suggest this is an ideal time to reassess mineral strategies.
Spring calving dairy and suckler cows are at particular risk of developing hypomagnesemia (grass staggers) post-turnout. Every litre of milk requires around 0.11g of magnesium to produce, therefore during early lactation, magnesium requirements for a typical dairy cow are doubled compared to the dry period.
To prevent, every producer should consider their grazing and magnesium supplementation strategies, which will differ from trace element provision. There are several types of magnesium supplement available.
“Where infrastructure allows, producers may choose to add a magnesium liquid, such as Rumag Aqua from Rumenco, to the drinking water. If this is to be done, all accessible water must be supplemented, as magnesium can be unpalatable,” added Mrs Williams.
While forage testing provides useful guidance, it only offers a snapshot of trace element status. Where farms have known trace element imbalances this year’s wet conditions are likely to amplify those issues.
Long-acting boluses are increasingly being used to provide consistent trace element supplementation, ensuring every animal receives the required intake
“Turnout is a logical time to administer a bolus,” said Mrs Williams.
“It provides peace of mind that cattle are supported during a period when mineral supply from grass can be unpredictable.”
Production gains seen in on-farm trials
On-farm trials in Northern Ireland have demonstrated performance benefits from bolusing cattle with EnduraBol Cattle, which provides sustained release of six trace elements (Copper, Cobalt, Iodine, Selenium, Manganese, Zinc) and three vitamins (A.D.E) for up to 240 days.
At Ashwoods Farm in County Fermanagh, 20 Angus-cross steers were split into control and bolused groups at turnout. After 183 days at grass, cattle receiving two EnduraBol Cattle boluses showed a 16.5% increase in liveweight gain, averaging 27kg additional liveweight per animal compared with the control group.
“Trace element status underpins immunity, growth and fertility,” said Mrs Williams. “In years like this, when mineral availability is uncertain, proactive supplementation can help protect performance and maintain momentum through the grazing season. Mineral planning is certainly something that should not be left to chance.”
