Effect of aleurone supplementation on glucose-insulin metabolism and fecal microbiome in untrained healthy horses

Aleurone is known as the layer within the bran fraction which is deemed to be responsible for the positive health effects associated with the consumption of whole-grain products. Studies in rodents, pigs, and humans report beneficial effects in five main areas: reduction of oxidative stress, immunomodulatory effects, modulation of energy management, digestive health, and vitamin and mineral storage. This is the first study to be performed in horses.Aim of the study was to investigate the effect of increasing doses of aleurone on postprandial glucose-insulin metabolism and the fecal microbiome in healthy untrained horses. Seven Standardbred horses (age 4 to 7 years, 4 ?, 3 ?) were supplemented with four different wheat aleurone ASP-01 doses (50, 100, 200, 400 g/day during 1 week), using a Latin Square model. On day 7 of each supplementation week, horses were subjected to a postprandial glucose and insulin follow-up and fecal samples were collected for 16S rRNA gene sequencing. Microbiome content and microbial community function was analyzed using common bioinformatics tools to identify differences between conditions.