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Insights on Preventing Grass Staggers

preventing grass staggers

Preventing Grass Staggers

Shaun Hambley offers some insight into preventing grass staggers


At this time of year cattle are often deficient in magnesium, owing to the rapid increase in grass growth. Because ruminants cannot store magnesium in the body, as they can most other minerals, grazing livestock require magnesium supplementation every day.

Magnesium levels in grass through the season are difficult to predict and would vary from one season to another largely due to weather patterns and the way we manage grass.

Potassium plays a key role regarding grass staggers as it indirectly reduces the animal’s ability to absorb magnesium. Potassium, with nitrogen, dominates the mineral profile of grass and together they drive vegetative growth. It is, therefore, not surprising that the amount of potassium in grazing follows the grass growth cycle where levels tend to peak in May, followed by a decline towards July and rising again in the autumn in line with the late flush of grass.

Potassium levels continue to rise year on year. There are several reasons for these increased levels in forage:


  • Changes in rainfall pattern
  • Targeting slurry on silage fields
  • Not checking soil K indices (57% UK soils have index 2 or greater)
  • Low sodium levels in soil

High levels of potassium in grass will cause a suppression of sodium (salt) which is the critical factor as sodium is essential for the transportation of magnesium across the rumen wall to be utilised by the animal. Therefore it’s through its undesirable effect on sodium that potassium exerts its influence on magnesium.
Avoiding staggers is very straightforward, the key guiding principles are:


  • Daily magnesium supplementation
  • Be aware of potassium’s impact on magnesium availability
  • Ensure stock have access to magnesium in a palatable form
  • Ensure free access salt is on offer


Cattle and sheep need to be supplied with the correct level of magnesium on a daily basis, especially during the critical 6 week period after turnout. Ideally magnesium supplements should be introduced 7-10 days before turnout to help correct any existing deficiency.

Mole Valley Farmers supply a range of minerals, blocks and buckets including:

Nutri-LINK Cattle High Mag Free Access minerals

Depending on the diet and situation use 150g per head per day preferably incorporated into the ration. If it is not possible, top dress the appropriate quantity (15kg per 100 cows per day) onto the silage.
If free access is the only option, this cannot be relied on as the sole supply of magnesium to prevent grass staggers. Magnesium chloride in the water or Hi Mag mineral buckets and blocks can also be used.
25kg bags are available for collection from your local Mole Valley Farmers branch or delivered direct to farm, minimum order 1 tonne. Read more.

MVF Cattle Tri Mag Mineral Buckets

Mole Valley Farmers Cattle Tri Mag mineral buckets have been formulated with three highly available and highly palatable sources of magnesium, to provide improved protection against grass staggers.  In addition to their improved availability, magnesium phosphate and magnesium chloride are included to enhance product palatability. We also only use magnesium oxide power to ensure a greater absorption by the animal when compared to the granular form commonly used by other suppliers. MVF Cattle Tri Mag buckets also contain a full complement of minerals, trace elements and vitamins.
20kg buckets are available for collection from your local Mole Valley Farmers branch or delivered direct to farm. We can also supply 100kg buckets delivered direct to farm (minimum order 4x100kg). Read more.

To place an order, or find out more about the products we sell please call your nearest MVF branch and speak to the Farm Sales Co-ordinator or alternatively, call Lifton Mill on 01566 780261. More information on the full range of mineral buckets and blocks can be found on our website

Source Details

Shaun Hambley, Alternative Feeds Product Manager and Nutritional Adviser, Mole Valley Feed Solutions

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