Diversity and abundance of the rumen and fecal methanogens in Altay sheep native to Xinjiang and the influence of diversity on methane emissions

This study aims to investigate the influence of diet roughage proportion on the methanogenic communities from the rumen and fecal samples in Altay local sheep native to Xinjiang and better understand the association of methanogenic diversity or abundance with methane emissions of the ruminants. In this study, the high roughage diet was found to cause more methane emissions for either maintenance or ad-lib group, but the total methanogenic abundance was not influenced by roughage proportion and showed no significant difference between groups. Furthermore, the denaturing gradient gel electrophoresis was conducted to reveal the difference in methanogenic diversity. Phylogenetic analysis showed that the sequences obtained were divided into three groups, affiliated to the genus of Methanobrevibacter, Methanocorpusculum and an unidentified methanogenic-like group. Of these sequences, the predominant diversity from the genus of Methanobrevibacter and the unidentified methanogenic-like archaeons in the rumen was found to be significantly induced by the high roughage diet, implying that the variation of diversity at the species or strain level might have an effect on methane emissions from the rumen. Further analysis showed that five methangenic sequences from the rumen were possibly associated with the differential methane emissions.