Feed Delivery Methods' Effects on Glucose, Insulin Response

There are a number of ways to help prevent insulin resistance (IR) or associated conditions like laminitis in horses, but did you know that how you feed your horse could be one of them? According to recently published study results, feeding methods that slow horses’ feed consumption rate can also reduce their insulin and glucose responses directly after the meal.

“We wanted to see if there were other things an owner could do from a management standpoint to minimize glucose/insulin responses to feed … simply by altering how they deliver the feed to the horse,” explained researcher Shannon Pratt-Phillips, PhD, associate professor at North Carolina State University's Department of Animal Science.

In the first of two experiments, Pratt-Phillips and colleagues investigated four different feed delivery methods' effects on the glucose/ insulin responses of eight mature healthy horses of varying breeds.

The researchers fed the horses a single concentrate meal (2 g/kg of body weight of a 26% nonstructural carbohydrate [NSC] pelleted feed) once per week, randomly assigning four separate feed delivery methods:

  • Control—an unaltered rubber bucket;
  • Ball—a bucket with four movable bocce-style balls (10.7 cm diameter) placed in it;
  • Waffle—a bucket containing stationary obstacles below the feed; and •
  • Water—an unaltered bucket with concentrate soaked in an equal portion of water for 20 minutes.

On treatment days, the researchers fitted the horses with a jugular catheter to collect blood samples. Between treatments, horses were housed in individual partially-covered runs and fed mixed grass hay with access to mineral blocks and water.

The research data revealed that both the ball and waffle treatments increased the time it took the horses to consume feed (TCF) by nearly 50% compared to control and water treatments. Additionally, the team found that the ball treatment produced the lowest glucose and insulin responses of the four treatments.

In a second experiment, performed nearly one year after the first experiment, the team evaluated the efficacy of the same four feeding methods over a four-day period on four healthy mature geldings.

The team found that TCF varied over the four-day period and concluded that, although further studies are likely needed, “obstacles in a feed bucket can be considered effective at maintaining increased TCF after multiple days of use.”

While not all IR or laminitic horses require concentrates in their diets, if a supplemental feed is needed, choose and feed carefully. “Select one with low levels of NSC, and try to feed it in as many meals per day as possible," Pratt-Phillips said. "Also try to slow down feeding rate by either using obstacles in your horse's feed tub, or even placing the feed into two or three feed tubs in his stall.”

The study, “The effect of different feed delivery methods on time to consume feed and the resulting changes in post-prandial metabolite concentrations in horses,” will appear in an upcoming issue of the Journal of Animal Science

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.