Owners should manage their horses to prevent or limit weight gain when pastures grow rapidly and increase in nutrient content during the spring and summer months. | Photo: iStock

Your horse came out of winter in good body condition; how can you keep that trend going as the grass greens?

Ever had a horse that stays in good flesh or becomes just slightly lean during a harsh winter, but then promptly expands as soon as warm weather hits? Seemingly overnight, just as the pastures turn green, this horse appears as if it could foal at any moment.

Although this might (or might not) be an exaggeration, rapid spring weight gain is not uncommon. In my experience, I have had two Thoroughbreds—usually a notoriously hard-keeping breed—that could maintain and gain weight on good-quality pasture and hay alone.

“With cool-season grasses at peak production in the spring and warm-season grasses at peak production in the summer, there is an increase in overall forage availability from pastures, leading to the potential for weight gain,” says equine nutritionist Bridgett McIntosh, PhD. “Rapidly growing pasture grasses in the spring and summer months are also higher in digestible energy (calories) and sugars, which contribute significantly to weight gain