How much magnesium is too much for a horse per day?

Question

16hh

Age 8

Approx 1150 lbs

Magnesium is known to be beneficial for insulin resistance. I need to know how many grams is too much as I work out a new feeding routine and supplementation plan. The supplement recommended has 5 grams of Mg, but another supplement I use and most feeds have it as well. Need to know what's too much.

I'm doing research tonight while I have time and want to know this cut-off. Vet and I are talking but she had to run out on an ER call and we were cut short. I'd like to still research with a max value for Mg in mind tonight. I'm only adding this so no one tells me to call the vet.

Thanks!

Answer 1

I just happen to have an article on my desk titled "Insulin Resistance:Many horse owners have found that magnesium supplementation gives them more control"  but it does not give a web source for the article.  If you google that you may find it.  I'll try to skim it quickly and see if I can find your answer.  I've been around horses with EMS but have not dealt with managing one first hand.

Combined sugar and starch content in the diet must be kept below 10%, including that from hay and pasture

Magnesium will only help if the horse is magnesium deficient.  Test must be done on a fresh blood sample

Ca:Mg ratio of 2:1 is ideal for mag. absorption.  This is important

Suggest having your horse's hay analyzed for Ca and Mg content/ratio

Here are the Magnesium supplements sources they list;

Mag Ox 56

Magnesium /Design Nutrition Equine

Magnesium 3000/MedVet Pharmaceuticals

Magnesium Oxide/Uckele Health and Nutrition

Su-Per Mag Calm/Gateway Products

Quiessence/Fox Den Equine

Metabolic Support/Platimum Performance

They end up saying you have to figure out how much your particular horse is deficient, and then use a supplement that doesn't have a lot of other ingredients.

Well, I  don't think that answered your question, but maybe it will help somewhat.  Good luck.

PS  I think this article was in the June 08 Horse Journal

Answer 2

Gosh, I really don't know, but I've been wondering that myself.  I'm not a horse owner, but I used to live in northeastern Nevada.  That part of the state is very rich in high yield gold mines.  Many of the mining companies own hundreds of square miles of desert in order to stake claim to the richest gold veins.  They often have feral Mustangs on their land.  Since the Mustangs are on private property, they are not managed by the BLM.  The mining company generally ignores them.  Since it's a high altitude desert, winters there are harsh and long with sub-freezing temperatures for weeks on end.  Ice and snow threaten access to and from the mines during the winter months, which is a real problem, considering the mines are worked 24/7 year round.  The mining companies salt their roads with magnesium chloride in an effort to reduce ice and snow.  The Mustangs are attracted to it and often stand about on the road to l**k up the magnesium chloride.  The very idea scared me, but no one else seemed very concerned.  Those Mustangs live as true wild animals with no one monitering them at all, so any cases of poisoning would go unnoticed.