What the Heck Is metabolic support horse feed?

http://www.coastalnewsnow.com/news/story/603272/with-half-of-britains-horses-overweight-bifid-launches-grainfree-lowsugar-feed-for-the-nations-gooddoers.html

Gentle horse feed for sensitive stomachs, designed to support comfortable digestion, hind gut health and easy nutrient absorption. A low sugar fibre-rich formula with natural ingredients to help maintain calm digestion and overall wellbeing.