Abstract: Five strains bacteria were isolated from piglets with representative edema disease clinic symptom and dissection symptom in a Jiangsu pig farm，namely JS0001,JS0002,JS0003,JS0004 and JS0005 respectively. The isolated bacteria were identified by their culture characteristics,morphology,dye characteristics,biochemical characteristics and serological test,and antimicrobial susceptibilities,hemolysin production,cytotoxicliy for Vero cell and pathogenilcity for mice were tested．The results showed that the isolates JS0001,JS0002,JS0004 and JS0005 produced β hemolysin,and JS0001,JS0002,JS0003 and JS0004 had high pathogenic for mice through abdominal injection．The five isolated bacteria were high sensitive to Furazolidon（FR）,Ceftriaxone（CRO）,Cefotaxime（CTX）and Amikacin（AN）,especially Ceftriaxone（CRO）,but resistant to Amoxicillin and Doxycycline．The JS0002 and JS0004 strain had cytotoxicity against Vero cell ,and were identified to be shigalike toxin escherichia coli．The results of the serological test showed that JS0002 and JS0004 O antigen serotypes were O₁₃₉, and JS0001 and JS0003 O antigen Serotypes were O₁₄₁.

Key words: piglet; edema disease; shigalike toxin escherichia coli; biological characteristic; antimicrobial susceptibilities; serological classification