The 57% hay and 43% barley (HB) diet we fed to the horses was
formulated to challenge the hindgut microbial ecosystem. Indeed it
contained a lower level of hay than the minimum recommendation of
1 kg of DM/day/100 kg of BW hay [29] and a higher amount of starch
than the maximum recommended level of 200 g of starch/meal/
100 kg of BW on the morning meal ([30]). As expected the HB diet
induced changes in the microbial hindgut ecosystem: we found an
increase of colonic total anaerobic bacteria, lactate-utilizing bacteria