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Magnesium plays an important role in maintaining healthy nerve and muscle function. Horses who are deficient in magnesium may show signs of nervousness, excitability, tightness, have muscle tremors and skin hypersensitivity. A deficient horse will build up lactic acid faster during exercise, causing fatigue quickly. This can result a poor tolerance to work, poor recovery and a tendency to tying up. When horses get excited, their bodies utilise magnesium to calm down and relax. The lower the magnesium level, the lower the threshold for new stress.

Only approximately 1% of magnesium is stored in the blood, the rest is stored in soft tissue and bone. This is why blood level magnesium tests are rarely indicative of an animal’s true magnesium status. A horse would be severely deficient and would be ill by the time a blood test would indicate a shortfall.

Horses have a limited ability to store magnesium. Magnesium is needed for calcium absorption. Without enough magnesium, calcium can collect in the soft tissues and may cause arthritic conditions. Not only does calcium collect in the soft tissues of arthritics, it is poorly, if at all, absorbed into blood and bones. However supplementing with more calcium is not necessarily the answer. This may amplify the problem. Excessive calcium intake and insufficient magnesium can contribute drastically to arthritic conditions. While magnesium helps horses absorb and retain calcium, too much calcium prevents magnesium from being absorbed. So supplementing with calcium without adequate magnesium may either create malabsorption or a magnesium deficiency. Whichever occurs, only magnesium can break this cycle. Supplementing with magnesium in moderate dosages can solve the problem of calcium deficiency.

Magnesium deficiencies are more inclined to be in spring, during periods of strong grass growth, and even in winter on pastures in areas where grass is fertilised (especially with Nitrogen). Grass in both circumstances is likely to be low in magnesium, sodium, and soluble carbohydrates, and most likely high in nitrogen and potassium. High potassium levels are likely to minimise the utilisation of magnesium. Sodium should always be available as needed, although sodium should not be over supplemented.

Magnesium Toxicity

At normal dietary concentrations of varying magnesium sources, it appears that it is unlikely severe toxicity is a problem. However magnesium should not be over supplemented, because any isolated chemical supplemented in excess has the potential to be antagonistic to other elements. When horses are showing signs of magnesium deficiency it is important to recognise whether that deficiency truly is the problem. Horses can show all of the symptoms below and be suffering with other issues, causing pain, fear or both as they tend to go together. Excessive magnesium will be excreted in the urine, but major overdoses have been linked to heart and renal problems, so it is important not to over supplement magnesium. It is dangerous territory to over supplement any isolated chemical!

Typical Symptoms of Magnesium Deficiency:

  • Fatigue

  • Unable to relax mentally & physically

  • Body tension

  • Not tolerating exercise-often becoming more excited, not settling down

  • Muscle tremors, twitches, all over body trembling especially after exercise

  • Tying up

  • Painful menstrual heats in mares

  • Teeth grinding

  • Irregular or pounding heart

Magnesium Aspartate* contained in Eco-Protect™ is the premium source known, it is highly water-soluble and when dissolved it is readily absorbed through the intestine wall.

Magnesium Aspartate* has a biological uptake which is much higher than most other magnesium supplements.

Balance is the key to success when supplementing horses. Due to environmental issues, we have to supplement most horses, however over supplementing will inevitably lead to problems.

When supplementing horses, try to keep things as simple as possible. Horses like all living beings, are just a bunch of cells. Every living cell absorbs nutrients, utilises these and then excretes waste. Therefore when the dietary needs are met we can afford to supplement less.

That is another article!

Leanne Franklin

© 2015 Equine Royale Ltd

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