Treat Well: Can Sugar Levels In Treats Affect A Horse With Insulin Issues?

Horses with insulin dysregulation absorb more sugar from feed and forage in their intestines than their healthy counterparts, which may affect blood glucose levels. Though horses consume sugars in their daily rations, horses with metabolic issues are often fed specific feeds that limit their consumption of nonstructural carbohydrates.

A study out of Australia has shown that feeding horses with equine metabolic syndrome or insulin dysregulation even a small treat can affect how their intestines absorb sugar.

For the study, researchers, led by Dr. Melody de Laat of the Queensland University of Technology in Brisbane, Australia, fed 10 ponies applesauce-coated bread slices twice a day; this added 25 percent more nonstructural carbohydrates (NSCs) to the ponies' diet. The treats didn't impact blood insulin levels, but it did change how ponies' intestines absorbed simple sugars after 10 days of being fed the treats.

“Insulin-dysregulation” means that affected horses and ponies release more insulin into the bloodstream than necessary after meals – specifically meals that include higher NSCs. Certain forages, grains, and sweet horse treats are high in NSCs.

Insulin dysregulation (ID) can cause a myriad of health problems, including laminitis; because of this, horse owners and caretakers are often diligent in feeding at-risk horses and ponies a specific diet to limit their intake of NSCs. However, they may fail to factor in the NSC content of treats.

To determine how treats affect ID horses, De Laat and her research team used 10 ponies for a study: six of the ponies were metabolically healthy and four experienced ID horses. All horses were from the Queensland University of Technology research herd. The average age was 13 years old; there were five mares and five geldings. The ponies all lived individually and ate a forage diet with an NSC of 9.9 percent.

Before the study began, a sugar absorption test was run and measurements of the ponies' plasma, blood glucose, and serum insulin responses to eating were taken.

Then, each pony was then given one or two slices of whole wheat bread coated in applesauce twice a day for 10 days. No pony refused the treat. How much bread each pony was fed was based on weight. The treat added between 1.5 percent and 3.6 percent NSC to the ponies' daily diets – an NSC increase of about 25 percent.

The same tests were then repeated. The scientists found that sugar absorption in the intestines was 1.6 times higher and that serum insulin after eating was 1.4 times higher. However, the treats didn't affect blood glucose, serum insulin concentrations, or fasting. This means that the ponies' intestines were able to absorb more simple carbohydrates, but their blood glucose and serum insulin levels were not affected.

This does not mean that there is no issue, the team notes. They say such “early changes” may eventually lead to changes in blood glucose and serum insulin levels if the treats were fed over a longer time period or if the treat's NSC content was increased. More research is needed.