Molecular diversity of bacteria in Yunnan yellow cattle (Bos taurs) from Nujiang region, China.

The rumen content of four Yunnan Yellow Cattle (Bos taurs) were collected to determine the bacteria diversity by using 16S rRNA gene sequence analysis. A total of 129 sequences were examined and the sequences were referred as 107 OTU (Operational Taxonomy Unit) according to the similarity level of 97% in gene sequence. Similarity analysis revealed that Yunnan Yellow Cattle had 12 sequences (10 OTU) shared 97% or greater similarity with cultured rumen bacteria Butyrivibrio fibrisolvens, Succiniclasticum ruminis, Ruminococcus bromii, Clostridium proteoclasticum, Ruminococcus flavefaciens, Pseudobutyrivibrio ruminis, Jeotgalicoccus psychrophilus, and Prevotella ruminicola, which accounting for 9.3% of the total clones (9.2% of the total OTU). The further 12 sequences (9 OTU) shared 90-97% similarity with cultured bacteria Clostridium aminobutyricum, butyrate-producing bacterium, Schwartzia succinivorans, Prevotella ruminicola, Eubacterium ruminantium, Ruminococcus albus, and Clostridium termitidis, also accounting for 9.3% of the total sequences (8.3% of the total OTU). The remaining 105 sequences (90 OTU) shared less than 90% similarity with cultured bacteria, accounting for 81.4% of the total sequences (82.5% of the total OTU). According to the phylogenetic analysis, all sequences were phylogenetically placed within phyla of low G+C subdivision (accounting for 72.1 and 72.5% of the total clones and OTU, respectively) and CFB subdivision (Cytophaga-Flexibacter-Bacteroides; accounting for 27.9 and 27.5% of the total clones and OTU, respectively). Among the examined clones, rare bacteria Jeotgalicoccus psychrophilus was detected in the rumen of cattle.