Is your horse nervous?

Is he highly anxious in numerous situations?

Do you wish there is something you could do?

There might be an easy fix...

One of the most common signs of magnesium deficiency is extreme nervousness.

Read on below to find out more about this essential mineral...

Nervousness is a sign of magnesium deficiency.

Magnesium (Mg) plays a number of important roles in your horse's body.

In his muscles, it attaches to ATP so that the ATP can be used by the muscle cells. If the Mg is not present, the ATP cannot be used, and the muscle would not be able to generate energy to carry out any functions.

It also plays roles in your horse's blood, as well as acting as an activator for many enzymes throughout the body. It is necessary for many of the enzymes that work with ATP.

Almost 60% of the Mg in your horse's body is in his skeleton, while another 30% is found in his muscles. The other 10% is found in various areas, including the blood and liver.

Mg is one mineral that the absorption of is not highly influenced by other minerals. Calcium, phosphorus, potassium, and aluminum all have little, if any effect on the absorption of Mg. It is also good to know that neither oxalate or phytase affect the absorption either.

Likewise, exercise appears to have little effect on the absorption rate.

Dietary Sources

Mg that your horse gets naturally from his diet is absorbed at a rate of about 40-60%. With most feeds containing around 0.1-0.3% Mg, it can be hit or miss whether or not a horse meets his daily needs.

However, inorganic forms that are often supplemented -- Mg oxide, sulfate, or carbonate -- appear to have a higher absorption rate at around 70%.

Magnesium Deficiency in Horses

Horses that are deficient in Mg show a variety of symptoms, including:

  • Nervousness/Flightiness
  • Muscle tremors
  • Ataxia (incoordination and unsteadiness)

Diets low in Mg also cause mineral clots to form in the aorta, the main blood vessel that carries blood from the heart to the body.

Magnesium Toxicity

Mg toxicity has not been studied in the horse. However, at normal dietary concentrations of varying Mg sources, it appears that there is little likelihood of toxicity being a problem.

The only time toxicity might be an issue is if Mg sulfate is used as a laxative to clear a blocked intestine. If it is overdosed, it can cause a toxic reaction, which has symptoms of kidney insufficiency, calcium deficiency, and intestinal damage.

Supplementing Magnesium to Horses

Many horses are supplemented Mg to try to calm them. There are a number of products on the market, including Ex-Stress:

Magnesium supplement for horses.

Sold by Jeffers Equine
(click on the logo to go to their page)

Click here for

Another popular supplement for Mg is Quiessence. These (and other commercial Mg supplements) are all good magnesium supplements, and work for many horses.

If you don't want to spend that much money, another option is simply to buy magnesium oxide from your local feed mill. It is straight Mg oxide, which is what is the main ingredient in most Mg supplements anyways.

This usually is sold under the name of MagOx or FeedOx, and is a supplement that cattle owners use to mix into their cattle rations.

As a result, its usually not displayed on the floor, and you will have to ask an associate for it.

You'll also probably have to specify that you want a cattle product, as the associate will probably be confused if you tell him or her that you are buying it for a horse.

In my experience it comes in a non-descript brown bag, usually in 50 pounds. Last time I bought it (sometime last year) it cost me $12 for the bag.

The great part about using MagOx is that it is so is fed at a rate of tablespoons per day, so that bag lasts forever!

To use it as an insulin resistance treatment, supplement 3 tablespoons/day for the first month, then reduce that to 1 tablespoon/day for maintenance.

I supplement all my horses with Mg, as it is so inexpensive and it is thought that many horses today are probably Mg deficient to some degree.

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