Estimations suggest that 1% of cattle in the UK will experience clinical grass staggers, with up to 30% of all clinical cases resulting in death and significant direct losses. A far larger percentage of animals, including ewes, will experience sub-clinical cases that may affect overall animal performance.
Grass staggers, otherwise known as grass tetany or hypomagnesaemia, is a very real threat for suckler and dairy cows at turnout as well as ewes post-lambing. However, it is easily managed by assessing and managing the on-farm risks and farmers are urged to consider their options as the potential for a rapid flush in grass growth increases.
Grass staggers is defined as a deficiency of available dietary magnesium. Magnesium is a key macro-nutrient in the diet and is essential for bone growth and maintenance, nervous system function and also as an aid to fibre digestion in the rumen.
Rapidly growing spring grass typically has a low magnesium content (0.1 to 0.2% in dry matter) which, combined with its low dry matter and rapid transit through the rumen, can result in very low levels of magnesium absorption into the animal’s bloodstream. Magnesium is predominantly stored in the bones of the animal and consequently is not readily available when dietary supply is compromised. Stock therefore rely on daily magnesium supplementation to maintain adequate blood magnesium levels at times where risk is increased such as spring, and autumn.
To help alleviate the risk of grass staggers, long fibre should always be available in the form of hay or silage, to help slow the transition of wet spring grass through the rumen. It is also essential to maintain dietary energy levels (notably starch and sugar) to help prevent excess rumen ammonia. Dry matter intake needs to be maintained, whilst an adequate supply of minerals, trace elements and vitamins, including a suitable supplementary sodium (salt) source is also essential to re-address the sodium to potassium ratio. Finally, and most importantly, it is vital to ensure stock have daily access to a suitable magnesium supplement.
Magnesium is typically an unpalatable mineral, so by presenting it in a molassed free-access lick, farmers can be assured that their stock have a reliable supplement to complement their diet.
NWF Cattle Spring Mag molassed mineral lick contains 15% magnesium along with a range of minerals, vitamins and trace elements, including sodium. NWF Cattle Spring Mag is suitable for feeding to breeding and lactating cows at risk of grass staggers to help supplement grazing at this time of year, and also comes with the extra benefit of added copper to help support good fertility and tight calving intervals.
Alternatively, NWF Magnesium is a molassed feed and mineral bucket containing 10% natural protein, 9 MJ ME/kg DM and 10% magnesium. Suitable for ewes after lambing, NWF Magnesium also contains high levels of selenium, cobalt, zinc and vitamin E, which are often found deficient in spring grass, and are especially important for good ewe health and performance throughout lactation.
Ideally, magnesium supplements should be offered up to two weeks pre-turnout to better prepare stock for changes. Then, by turnout, they are familiar with the supplements and are not faced with a deficit.
Grass staggers is a common, well known challenge at turnout that can be fatal, however, it’s easily avoided by predicting where the main risks are and addressing them with suitable magnesium supplements.
Call NWF Agriculture on 0800 756 2787 or email email@example.com for further information, prices and advice.