What are nonstructural carbohydrates and how do they differ in feeds fed to adult horses? How are they digested and assimilated in the adult horse?
The references cited below are the latest research in the area of carbohydrate analysis and digestion in horses. Dr. Rhonda Hoffman is now a faculty member at the Virginia Tech Middleburg Equine Research Center and would be a good contact for you. The short version is that NSC (nonstructural carbohydrates) are measured using the ruminant fiber system (NDF system) and Dr. Hoffman has found that further partitioning the NSC into two fractions is helpful in describing feeds for horses. The NSC is analyzed for simple, hydrolyzable carbohydrates (water soluble sugars and starches). The remaining NSC is called “rapidly fermentable carbohydrates” and consists of complex, insoluble starches, galactans, fructans, pectin and some other minor componants. An important finding was that in horse grain mixes, most of the NSC is hydrolyzable carbohydrate, while in most forages fed to horses only about one-third of the NSC is hydrolyzable carbohydrate and two-thirds is in the rapidly fermentable CHO fr
