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Magnesium or Die


Magnesium at Turnout 

Well here we are yet again at that time of the year where I have that ‘conversation’ with the Editor of the Newsletter on how I can tell you about magnesium supplementation without repeating what I said this time last year (and the previous 20 years come to that!) My usual strategy for articles would be to explain all about the problem and the cause and then to look at potential solutions and how they work. However, this annual hot potato is rather different and calls for an alternative approach I feel.
OK so “in for a penny, in for a pound”, let’s go straight for the take home message and work back from there!

If you don’t supply sufficient magnesium to your cattle or sheep when you turn them out, they will die.
Well that wasn’t too difficult was it? OK, so let’s fill in the gaps for you. It may have a variety of names depending on where you are in the country or perhaps if you are a vet or rather more poignantly, a knacker man! However you describe it, hypomagnesaemia, or grass staggers, can, and will, kill your stock if you do not supplement them sufficiently.
Everyone knows about grass staggers and how to prevent it but every year far too many animals die from this condition. In borderline situations, herd performance will suffer so even if you do not lose any animals it is highly likely that profitability will be affected.
Remember that your stock cannot store magnesium so they need to be supplied with the correct amount every day. On the plus side, because animals cannot store magnesium, you can correct the situation relatively quickly. Despite this, it never fails to amaze me just how many magnesium deficiency problems arise every year. Magnesium is not expensive or difficult to use so please ensure that your stock are adequately supplied this grazing season and don’t forget that grass staggers doesn’t just occur at turnout, it can arise at any time during the grazing season or even in housed cattle! 

I remember clearly one evening last summer when a colleague rang me to share his despair as he had just driven many miles to collect some bags of magnesium chloride to take to a farmer who had “lost several cows” with grass staggers and who hadn’t been using any magnesium. Unfortunately, I am sure there will be several repeats of this scenario this year but please don’t let it be you because I have decided that the first person that I hear of in this situation this year will be writing this page for me next spring – You have been warned!!

Calcined Magnesite (Cal-Mag)
A 50% magnesium powder, highly consistent and excellent bioavailability, supplied in 25kg bags. Often used in TMR feeding, this product is an effective source of magnesium supplementation. Cal-Mag can also be added to your mineral supplement, as a TMR Farmpack to provide an all in one bag solution.
Usage rate:
Cows up to 90g/head/day.
Sheep up to 10g/head/day
Available from all branches or direct delivery to farm 25kg bags.

Magnesium Chloride (Mag Flakes)
A 12% water soluble magnesium product for use in drinking troughs and mixer wagons. It is important to ensure that stock only have access to treated troughs and that all rivers, ditches and untreated water sources are fenced off.
Usage rate
Cows 150-200g/head/day.
Sheep 30–60g/head/day.

Available from all MVF branches or direct delivery to farm in 25kg bags.

Nutri-LINK Cattle High Mag minerals
Incorporate with feed or can be used free access to provide 150-175g/head/day.
Available from all MVF branches or direct delivery to 

Source Details

John Lawrence, Mineral Supplements.

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