Diversity of Streptococcus spp. and genomic characteristics of Streptococcus uberis isolated from clinical mastitis of cattle in Bangladesh.

Out of 105 samples examined 56.2% (59/105), 17.14% (18/105), 9.52% (10/105) and 22.9% (24/105) samples were positive for , , and , respectively. This study was then directed to the determination of diversity of spp. through the sequencing of . A total of eighteen of the samples from CCM (22.5%) but none from the AHC were positive for spp. by cultural and molecular examination. Sequencing and phylogenetic analysis of identified 55.6, 33.3, 5.6 and 5.6% of the isolates as , , and , respectively. Considering the high prevalence and worldwide increasing trend of in mastitis, in-depth molecular characterization of was performed through whole genome sequencing. Five of the strain isolated in this study were subjected to WGS and on analysis two novel ST types of were identified, indicating the presence of at least two different genotypes of in the study areas. On virulence profiling, all the isolates harbored at least 35 virulence and putative virulence genes probably associated with intramammary infection (IMI) indicating all the isolated in this study are potential mastitis pathogen. Overall findings suggest that encountered in bovine mastitis is diverse and might be predominantly associated with CM in the study areas. The genome carries an array of putative virulence factors that need to be investigated genotypically and phenotypically to identify a specific trait governing the virulence and fitness of this bacterium. Moreover, the genomic information could be used for the development of new genomic tools for virulence gene profiling of .