Thehorse.com - Full Article
By Clair Thunes, PhD
Jan 11, 2016
Q. I live in an area that’s selenium deficient. Why is selenium important for my horse’s health, and what is the best way to supplement it in his diet?
A. Selenium is a trace mineral, meaning that it is required in the horse’s diet in trace amounts measured in milligrams. Examples of other trace minerals include copper, zinc, iron, manganese, and iodine. In comparison macrominerals—such as calcium, phosphorous, magnesium, sodium and potassium—are needed in gram quantities.
Even though selenium is needed in tiny quantities it plays a number of very important roles...
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