Abstract: In order to determine the antibiotic resistance of pathogenic Escherichia coli (E.coli) in Guangdong province,a total of 62 E.coli isolates were collected from the diseased geese of four breeding goose farms in 2012.The susceptibilities of 62 isolates to 17 antimicrobials were determined by agar dilution method.The results showed that the resistance of the isolates was serious and the resistance rates to most of the antimicrobials were over 60%.Only cefoxitin, ceftazidime and colistin remained effective to the isolates. Combined antimicrobial susceptibility testing,it showed that doxycline and florfenicol had remarkable synergy activity against multi-drug resistant E.coli strains, with FIC varied from 0.375 to 0.75.Twenty-four strains were divided into 17 types by the test of PFGE analysis.43.5%,34.8% and 21.7% isolates belonged to phylogenetic group D,A and B1,respectively.This study might provide theoretical basis and reference basis for clinical medication.

Key words: breeding geese; Escherichia coli; antibiotic resistance; PFGE molecular typing; phylogenetic analysis