Elevated nonstructural carbohydrate (NSC) values in pasture forages can cause adverse health effects in some horses.
The objectives of a study, conducted at the University of Minnesota, were to determine the impact of different forage species on blood glucose and insulin concentrations of horses throughout the grazing season.
Research was conducted in July (summer) and September (fall) in St. Paul, MN. Alfalfa, mixed perennial cool-season grasses (e.g. orchardgrass and bluegrass), and teff pastures were grazed by six horses. Jugular catheters were inserted 1 hour before the start of grazing and horses had access to pasture each day from 8:00 am to 4:00 pm. Blood samples were collected from each horse before being turned out (0 hours) and then at 2-hour intervals following turnout. Plasma and serum samples were collected and analyzed for glucose and insulin, respectively. Corresponding forage samples were also taken by hand harvest.
Teff generally had lower equine digestible energy, crude protein, and NSC compared to the other forages. Differences in peak insulin were observed between horses grazing cool-season grasses and teff during the fall grazing.
These results suggest grazing teff, especially in the fall, could lower the glucose and insulin response of some horses. For more information on this research, visit https://bit.ly/2wZKT0O.