Changes in fibre-adherent and fluid-associated microbial communities and fermentation profiles in the rumen of cattle fed diets differing in hay quality and starch amount

Until now, effects of elevated concentrations of sugar in hay in combination with different proportions of grain-based concentrate feeds have not been investigated with respect to the rumen microbial ecosystem. Therefore this study was designed to evaluate the differences between a common ration for dairy cows consisting of 60% fibre-rich hay (57.7 % neutral detergent fibre (NDF) in dry matter (DM)) + 40% starchy concentrate feeds and a high-sugar energy-rich hay (6.89 MJ NEL/kg DM, 46.3% NDF in DM) with graded amounts of starchy concentrate feeds (40%, 25% and 0% concentrate) on the ruminal ecosystem by using Illumina Miseq paired-ends sequencing technology.