b'NUTRITION KRISTEN JANICKI, MSTheHorse.com/NutritionA Quick Guide to MicronutrientsLearn how these vitamins and minerals affect nearly everyphysiological function in the horses bodyM icro: a prefix originating from the Greek letter , meaning small. Though they make up only a tiny part of horses diets, micronutrients play big roles in major physiological functions, ranging from bone and muscle perfor-mance to digestion to hormone signaling. Lets dive into the world of micronutrients to learn more.MineralsBy definition, minerals constitute any naturally occurring, pure inorganic (meaning without carbon) substance. Remember that periodic table from chemistry class? On it you will find a collection of minerals that are present on earth. After countless hours of research, nutritionists determined the proportion of these minerals necessary to sustain equine life. Minerals required in the equine diet fall ISTOCK.COMinto two categories: macrominerals and microminerals (see tables on page 24). What makes a mineral macro or micro?Classes of horses that might need supplemental minerals and vitamins include young, growing The amount a horse requires daily. If youhorses, lactating broodmares, and high-level athletes.glance at the National Research Councils Nutrient Requirements of Horses (2007), Manganesecutting or consumption, and region in youll find macromineral requirements Cobalt which it was produced, to name a few. listed as grams per day and microminer- The small intestine serves as the majorFor mature pasture pets a good-quality als as milligrams per day.site of mineral digestion and absorption,forage source can provide most, if not Macrominerals include: after which minerals proceed to variousall, of the daily required minerals. In allSodium tissues where theyre needed to assistother cases youll need to fill mineral gapsChloride almost every physiological function in thewith either concentrates or supplements.Potassium body. Many are multifunctional, servingThis includes young, growing horses,Calcium horses structure, fluid balance, muscles,lactating broodmares, and performancePhosphorus nerves, immunity, protein synthesis,horses. In some casesand this is oftenMagnesiumcarbohydrate metabolism, enzymes, anddictated by geographic locationforageSulfurhormones.levels of certain minerals (such as copper, Microminerals include: Because forages constitute most ofselenium, or zinc) can be low enough toIron the equine diet, they do the heavy lift- warrant additional supplementation evenZinc ing of supplying minerals. But, just liketo idle horses, says Mieke Holder, MS,Iodine forage quality, forage mineral contentPhD, assistant professor of nutrition andSelenium depends on various factors, such as theenvironmental impact in the UniversityCopper species of grass or legume, maturity atof Kentuckys Department of Animal and TheHorse.com | The HorseSeptember 201923'