Top 5 horse pasture research discoveries
Over the years, University of Minnesota Extension's pasture-related research has helped horse owners choose ideal pasture forages and keep perennials on the landscape.
We compared multiple forages that can keep horses healthier pastures and help owners reduce feed costs compared to feeding hay - a win-win-win for the environment, for horses and for horse owners.
1. Grazing perennial cool-season grasses
In multiple research studies, we found that horses prefer Kentucky bluegrass with a lesser preference for orchardgrass when planted by themselves. We then determined that horses preferred mixtures of endophyte-free tall fescue, perennial ryegrass, Kentucky bluegrass and timothy. This mixture also yielded well, withstood grazing pressure and met the nutritional needs of most classes of horses.
2. Grazing annuals
Grazing cool- and warm-season annuals were evaluated in two separate studies. We found that annual ryegrass, a cool-season annual, was a good option for horse owners looking to extend the grazing season or when in need of a quick-growing emergency forage.
In a separate study, we found that teff, a warm-season annual, could be used in Midwest horse pastures as an emergency forage or to maximize grazing during the summer slump commonly seen in perennial cool-season pastures. Horses diagnosed with metabolic conditions may benefit from grazing teff as it has a lower nonstructural carbohydrate content.
3. Grazing legumes
We found that while alfalfa was the highest yielding legume, horses had a stronger preference for clovers. While legumes can be good pasture species for horses diagnosed with metabolic disorders due to lower levels of nonstructural carbohydrates, they tend to be more calorically dense, which can lead to weight gain.
4. Identifying key differences between forage types
We compared teff, alfalfa and cool-season grasses (like Kentucky bluegrass) and found that teff had lower amounts of nonstructural carbohydrates, digestible energy and amino acids and higher fiber values compared to cool-season grass and alfalfa.
When grazed by horses, blood insulin levels were lower for horses grazing teff compared to cool-season grasses in the fall and late fall. Horses grazing teff had similar blood amino acid responses compared to the other forages, suggesting that the lower amino acid content of teff is not detrimental to mature horses in the maintenance stage of life.
5. Grazing cover crops
Cover crops are commonly used to provide environmental benefits and can extend the grazing season. We evaluated cover crops in horse pastures and found that berseem clover was the lowest producing forage, but the most preferred by horses. Horses did not like turnip and radish as much as they liked berseem clover.
All forages met digestible energy and crude protein requirements for adult horses at the maintenance stage. We placed a priority on preference and concluded that berseem clover, annual ryegrass, and winter rye were suitable cover crops to extend the grazing season in horse pastures.