What the Heck Is low calorie horse feed?

https://blogfreely.net/stubbaiibw/horse-feed-for-horses-requiring-condition-what-to-pick-and-the-reason

Gentle horse feed for sensitive stomachs, designed to support gut comfort, intestinal health and efficient nutrient uptake. A low-starch fiber-rich formula with naturally sourced ingredients to help maintain settled digestion and general wellbeing.