What the Heck Is low starch fibre feed?

https://horse-feed-products556.opalvector.com/posts/horse-feed-for-balanced-nutrition-a-useful-guide

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