In many cases, laminitis is easily provoked by feeding excess carbohydrates through both pasture and grain consumption. While there is no absoulete method to prevent laminitis, prevention and treatment can be managed through control of weight, supplementations and the pastures horses are allowed to graze. In general, mature plants that are high in fiber are considered to have low levels of carbohydrates, however this rule doesn’t always work as the environmental conditions largely impact carbohydrate levels. Once diagnosed with laminitis, management of sugar intake is the only proven way to manage the disease with limited lasting effects.
The first step in understanding how to prevent and manage laminitis on pasture is identifying those predisposed. Easy keeper breeds like ponies, Morgans, and donkeys are more susceptible to laminitis then breeds like thoroughbreds with high work loads though there are always exceptions. Horses who have previously been affected with laminitis or are affected by other nutrition related diseases are at an increased risk of laminitis.
For most horses, total pasture restriction is not always a feasible or desirable option for financial, welfare, and health reasons but for horses at risk of laminitis normal pasture turnout is not viable either. Horse pastures should contain either C4 species like Bermuda and summer prarire grasses, or C3 species like orchard, timothy and brome, or species that tend to accumulate low concentrations of NSC. C3 or ‘cool season’ grasses grow better under cool, temperate climates (10-25?C temperature while C4 or ‘warm/tropical season’ grasses do better in 15-40?C temperatures. C3 plants store fructan in the entire stem base in the plant and have no self limting mechism so NSC levels don’t have a cap while C4 species store starches and accumlate in leaf tissues, once these cells are full they stop producing starch so the process is self- liminting. The location of a pasture along with many environmental factors affect the species that is best for a lamninitic horse, overall C4 species accumalte lower levels of NSC but can not grow in colder environments. In many situations it is not possible to ensure pastures are grown with the best species of grass but there are many other ways of preventing high levels of NSC intake.