Spring is here and the plants are new and fresh. The pretty lush grasses that green the countryside in April and May are young, tender, and very tasty for a horse. Unfortunately, these young grasses are also low in the fiber that horses need and are high in the soluble carbohydrates that can upset the sensitive microbiotic balance in a horse’s gut.

Equine veterinarians at the University of Illinois Veterinary Teaching Hospital in Urbana say that, since horses are natural grazers, they need a diet high in fiber such as that found in long-stemmed, mature forage grasses. They encourage owners to use caution when turning horses out on pastures filled with young green grass.

Grass Founder

Young grasses are higher in soluble carbohydrates than mature ones. Large amounts of these carbohydrates can overload the gut, disturbing the balance of natural bacteria. As large numbers of natural gut bacteria die, they release a surge of a bacterial toxin called endotoxin and factors that could trigger laminitis.

The alterations in gut flora and release of trigger factors can cause acute signs of laminitis in predisposed horses, such as overweight horses, those with a previous history of laminitis, and those with Cushing’s disease