Comparative analysis of genetic characterization of β-lactam-resistant Escherichia coli from bulk tank milk in Korea.

Although E. coli isolates were isolated from bulk tank milk, and not the clinical mastitis samples, the presence of the phylogenetic groups B2 and D, and the serogroups O15 and O157, which harbor antimicrobial resistance genes and virulence factors, can pose a threat to public health.