Often I am asked to consult on nutrition for a horse that was sold as a well-behaved, quiet horse, but has increasingly become spooky, twitchy, short-strided, easily fatigued and girthy in their new home. The buyer will often suspect that the horse has been drugged, but usually the cause is much less sinister.
While not a fail-proof test, I find if I run my finger from wither to girth and the horse flinches, magnesium deficiency is often the culprit.
Magnesium has many roles in the body.
Magnesium is a cofactor in more than 300 enzyme systems that regulate diverse biochemical reactions in the body, including protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation [1-3]. Magnesium is required for energy production, oxidative phosphorylation, and glycolysis. It contributes to the structural development of bone and is required for the synthesis of DNA, RNA, and the antioxidant glutathione. Magnesium also plays a role in the active transport of calcium and potassium ions across cell membranes, a process that is important to nerve impulse conduction, muscle contraction, and normal heart rhythm [3].
(National Institute of Health Office of Dietary Supplements)
Our magnesium supplement is aptly called "Calm Mix". It is a blend of magnesium, B vitamins and a prebiotic. It is an off-white, sometimes more pinkish powder - depending on the batch. We sell it in 3kg or 5kg bags for $30/kg.
Calm Mix is "magic" because it works in a very short space of time - usually in days. I encourage owners to double-dose for two days and then drop back to one scoop a day. Often owners will have dramatic results in improved behaviour, energy levels, and movement. Unlike some other brands, we don't add any ingredients to improve palatability. Some fussy eaters will initially reject Calm Mix, and in that case I recommend starting with a teaspoon over two or even three feeds in a day until they become accustomed to the taste.
Calm Mix will only work to improve those symptoms if a magnesium deficiency is the source of the problem. Other possibilities include: poor saddle fit, requiring dentistry, muscular or skeletal pain, overfeeding of 'heating' feeds, or "green on green" (an inexperienced rider giving confusing or contrary aids to a horse that is overstimulated or uneducated).
Dosage:
The amount of magnesium required will very much depend on the individual. Some horses do very well on one scoop a day - others who may be in heavy work or required to be very gymnastic, such as reining horses or dressage horses may benefit from higher doses. The best way to tell what works best for your horse is to experiment. If they are not getting enough, the symptoms will return. If you are giving them too much, they will scour.
If those symptoms sound familiar to you, give Calm Mix a try.
Institute of Medicine (IOM). Food and Nutrition Board. Dietary Reference Intakes: Calcium, Phosphorus, Magnesium, Vitamin D and Fluoride. Washington, DC: National Academy Press, 1997.
Rude RK. Magnesium. In: Coates PM, Betz JM, Blackman MR, Cragg GM, Levine M, Moss J, White JD, eds. Encyclopedia of Dietary Supplements. 2nd ed. New York, NY: Informa Healthcare; 2010:527-37.
Rude RK. Magnesium. In: Ross AC, Caballero B, Cousins RJ, Tucker KL, Ziegler TR, eds. Modern Nutrition in Health and Disease. 11th ed. Baltimore, Mass: Lippincott Williams & Wilkins; 2012:159-75.