Adobe stockPasture makes up a large portion of the forage in many horses diets, but how can owners calculate exactly how much their horse eats when he is grazing? Kelly Vineyard, PhD, of Purina Animal Nutrition explains the best way to estimate how much grass your horse eats during turnout, and how to factor that into his daily forage ration.This podcast is an excerpt of our Ask TheHorse Live Q&A, Managing Your Horses Weight Through Thick and Thin. Listen to the full recording here.About the ExpertKelly Vineyard, MS, PhDKelly Vineyard, MS, PhD, is a senior nutritionist in equine technical solutions with Purina Animal Nutrition. She consults with veterinarians, professional riders, and horse owners across the United States and is directly involved with new product innovation, research, and technical support at Purina. Vineyard earned her BS in animal and dairy sciences from Auburn University and her MS and PhD in animal sciences from the University of Florida. Her doctorate research focused on the effects of omega-3 fatty acid supplementation on immune function in horses. Vineyard is a frequent lecturer on equine nutrition topics, with expertise in omega-3 fatty acids, immune function, and performance horse nutrition. She is an avid dressage rider and is proud to have earned her USDF bronze and silver medals on an off-track Thoroughbred.