Proper nutrition is the most important contributor to equine health and well-being. Responsible horse keepers feed their animals a healthful, nutritionally balanced diet portioned out in quantities that suit the age, size, and activity level of each horse. Thriving horses that stay healthy and strong into old age are those whose nutritional needs are being met. Leading equine nutritionist Melyni Worth explains the many ways in which diet affects a horse's health, temperament, and performance, I and then goes on to provide a detailed study of equine nutritional requirements. Horse owners will understand the roles played by fats, proteins, minerals, electrolytes, and vitamins and will learn how to evaluate weight and overall well-being and plan a corresponding diet. Year-by-year concerns are addressed here, as well as the specific needs of brood mares, performance horses, and other working animals. Worth also stresses the importance of giving horses plenty of access to pasture and explains the benefits of additives and herbal supplements. Common health problems such as colic, cribbing, and ulcers can often be corrected through a change in diet. Worth discusses possible solutions and also helps owners of horses with more complicated health needs. Challenges such as insulin resistance, Cushing's disease, metabolic bone disorder, and tying-up syndrome can all be managed or improved by carefully monitoring the horse's feed.