The basis of equine nutrition

Equine nutrition plays the basis for maintaining the health, performance, and overall well-being of horses. Horse owners and caretakers should understand the fundamental principles of equine nutrition, encompassing the essential nutrients, dietary requirements, and feeding strategies that are integral to the equine diet. By understanding these basics, informed decisions to optimize the nutrition of their animals can be made that are crucial for the health and longevity of horses. A balanced diet ensures the availability of essential nutrients, which are required for growth, reproduction, energy production, and immune function. The digestive physiology of horses is unique, reflecting their evolutionary history as herbivores. The key components of equine nutrition that should be considered include various macronutrients and micronutrients, as well as feeding management.

Horses require a variety of nutrients for optimal health. Macronutrients include carbohydrates, proteins, and fats. Carbohydrates, often primarily derived from forages, typically are the main energy source for horses. Proteins, composed of amino acids, are essential for tissue repair, growth, and enzyme function. Fats provide concentrated energy and are also can be incorporated into the diet to aid in maintaining coat condition – a benefit often favored by horse owners. Forages, such as hay and pasture, are integral to the equine diet. The digestive system of horses is designed for a high-fiber, plant-based diet. The cecum and colon play a central role in fermentation, breaking down fibrous materials and producing volatile fatty acids that serve as an energy source. Forages provide fiber for proper gut function and help prevent digestive disorders like colic. Forages also supply vitamins and minerals, particularly fat-soluble vitamins A, D, and E, as well as calcium and phosphorus. Access to good-quality forage should be the basis of any equine feeding program. Concentrate feeds, including grains and commercial feeds, are often used to supplement the diet when additional energy and other nutrients are required. However, overreliance on concentrates can lead to imbalances and health issues. When introducing concentrates, it is crucial to do so gradually and in appropriate amounts, taking into consideration the horse’s activity level and metabolic rate. Micronutrients, such as vitamins and minerals, are essential for various physiological functions. Vitamins play roles in metabolism, immune response, and overall health. Most vitamins are obtained from the diet or synthesized by gut microbes without need for supplementation. Minerals like calcium, phosphorus, magnesium, and trace minerals are important for bone health, muscle function, and enzyme systems. Providing a balanced mineral supplement or through a fortified concentrate is vital when the mineral content of forages is insufficient, which occurs frequently. Water is often the most overlooked nutrient, yet it is the most critical. Horses require access to clean, fresh water to support digestion, thermoregulation, and overall health. Dehydration can lead to colic and reduced performance.

Feeding strategies should be tailored to individual horses based on their age, activity level, metabolism, and health status. Horses in different life stages have varying nutritional requirements. While the requirements of mature horses at maintenance can often be met on a diet consisting almost entirely of forages, with supplementation only required to meet deficient nutrients, optimal nutrition to promote growth and support performance may require growing, performing, or breeding animals to have requirements that may be more challenging to meet on an all-roughage diet. Proper body condition scoring is a valuable tool for evaluating the adequacy of a horse’s diet and adjusting feeding plans accordingly. While some mental and health concerns can be alleviated or prevented by maintaining horses on pasture, obesity and related health issues may be more prevalent with such horses if forage intake is unlimited, potentially predisposing horses to health problems such as insulin resistance or laminitis. These animals often require specialized diets with limited carbohydrates and controlled calorie intake. Consulting with a veterinarian or equine nutritionist is crucial when designing diets for horses with special needs.

Equine nutrition is a multifaceted topic with far-reaching implications for the health and performance of horses. Understanding the basics of equine nutrition, including the role of macronutrients, micronutrients, forages, and concentrates, allows horse owners to make informed decisions regarding their animals’ diets. Adhering to proper feeding strategies and considering individual horse requirements will contribute to the overall well-being of these animals.

Biographical Sketch for Dr. Brian D. Nielsen
Dr. Nielsen completed his undergraduate degree in Animal Science at the University of Wisconsin – River Falls and received both his M.S. and Ph.D. from Texas A&M University. He currently is a professor of Equine Exercise Physiology in the Department of Animal Science at Michigan State University where he has a teaching and research appointment. Nielsen has authored 83 peer-reviewed papers and 241 book chapters, conference papers, and abstracts, as well as 67 popular press articles. He has given 65 invited international talks in countries such as Australia, Austria, Brazil, Canada, England, France, Germany, Italy, Mexico, Northern Ireland, Norway, Spain, Slovenia, Sweden, Turkey, and the United Arab Emirates and has given 145 invited talks at national meetings and within the state of Michigan. He has secured $2.8 million in research funding. He is an active member of the American Society of Animal Science, the American Registry of Professional Animal Scientists, and served as the President of the Equine Science Society – an organization that presented him with the “American Feed Industry Association Award in Equine Nutrition Research” in 2017 and the “Outstanding Young Equine Professional Award” in 2001. Additionally, he was awarded the “Outstanding Teacher Award” at the Midwest Section of the American Society of Animal Science and the American Dairy Science Association in 2005 and the “Equine Science Award” by the American Society of Animal Science and Equine Science Society in 2010. Besides having served on the editorial board for the Journal of Animal Science, the Journal of Equine Veterinary Science, The Professional Animal Scientist, and the international journals Comparative Exercise Physiology and the Journal of Istanbul Veterinary Sciences, he is a Diplomat in the American College of Animal Nutritionists and served on the National Academy of Sciences Committee on Nutrient Requirements of Horses. Throughout his academic career, he has maintained involvement in the industry by breaking and galloping racing Quarter Horses and Thoroughbreds for nearly 35 years and became a licensed racehorse trainer in 1997.