Analysis of milk-derived isolates of E. coli indicating drug resistance in central Ethiopia.

Mastitis is one of the most important diseases in dairy cows throughout the world and is responsible for significant economic losses to the dairy industry. This study was performed to characterize the genetic basis of drug resistance in Escherichia coli isolated from cases of clinical and sub-clinical bovine mastitis. A total of 224 California mastitis test (CMT)-positive milk samples were collected from December 2015 to April 2016 to characterize the phenotypic and genetic basis of antimicrobial resistance in E.