by Dr. Clair Thunes PhD, Nutritionist for EnviroEquine & PET ~
While we often think of horses with metabolic issues as being overweight, for some this is not the case. Feeding the underweight horse with conditions such as insulin resistance or pars pituitary intermediary dysfunction (PPID or often referred to as cushings) can be a struggle as feeds need to be low in starch and sugar. Starches and sugars raise blood glucose levels. Due to reduced insulin sensitivity, these horses have to secrete more insulin than a horse with normal insulin sensitivity in order to clear the glucose out of the blood into muscle tissue.
The reason why we care about this raised circulating insulin is that research has shown that horses with higher levels of circulating insulin are at a greater risk of developing laminitis. In fact, in some studies laminitis has been induced by injecting insulin. So, if your horse is resistant to insulin such that increased blood glucose requires the secretion of higher than normal levels of insulin, you do not want to use feeds high in starch and sugar, which are often referred to as non-structural carbohydrates or NSC. It is typically recommended that diets for these horses maintain at a NSC content of 12 percent or less on a dry matter basis.
For horses in this category that need to gain weight, extra calories outside of those provided by forage need to come from non-starch feed ingredients such as those with fermentable fibers and higher fat content. Traditionally, these have included sugar beet pulp (actually low in sugar despite the name), soybean hulls, vegetable oils and rice bran (although it is potentially too high in starch for some horses) as well as commercial feeds that include these ingredients. A new ingredient that is high in digestible fiber as well as providing good levels of fat while being low in NSC is hemp hulls.
Like soybean hulls and almond hulls, hemp hulls are the casings that are found around plants’ seeds. They provide more calories per pound than typical forages, although slightly less than most grains. Hemp hulls contain large amounts of fiber with approximately 40 percent acid detergent fiber (ADF) and 55 percent neutral detergent fiber (NDF), plus under 10 percent NSC. With a minimum fat and protein content of 10 and 12 percent respectively, hemps hulls are a great option for horses needing to gain weight but that need to watch their NSC intake.
Equine Evolve by EnviroEquine is made of 100 percent hemp hulls milled from hemp seeds grown in the United States. This hemp is grown using organic farming practices and the seeds and hulls go through an exacting quality control process where they are tested for THC and cannabinoid content before and after processing.
Many horses with PPID also need some topline support, as their condition means that they struggle to maintain lean muscle mass. Equine Builder is a complete profile of easy-to-digest protein that provides all essential amino acids and is an excellent choice for this situation. Also low in NSC, this feed is an excellent choice for the metabolic horse needing topline support.