Anti-microbial susceptibility for east1 + Escherichia coli isolated from diarrheic pigs in Korea

The in vitro susceptibilities of 128 isolates of east1 + Escherichia coli from pre-weaned and post-weaned pigs with diarrhoea were tested with nine commonly used anti-microbial agents by an agar dilution minimal inhibitory concentration (MIC) procedure according to National Committee for Clinical Laboratory Standards guidelines. For the isolates from preweaned and post-weaned pigs, most of them were susceptible to low concentrations (MIC90) of tetracycline (4 and 2 microg/ml), ceftiofur (2 and 2 microg/ml), and colistin (4 and 2 microg/ml). Marked resistance was found in others.