Abstract
Bacteriological examination of 250 faecal swab samples collected from diarrheic, apparently healthy and freshly dead rabbits acquired from commercial fattening farms in different localities from Alexandria governorate (Egypt) showed that 152 samples (60.8 %) were positive for E. coli isolation. The prevalence of E. coli was 57.43% in apparently healthy rabbits, 70.12% in diarrheic rabbits and 53.23% in freshly dead rabbits. Twenty E. coli isolates were serologically identified as O146 (n= 4), O158 (n= 4), O44 (n= 4), O125 (n= 3), O169 (n= 2), O148 (n= 2) and O157 (n= 1). Antimicrobial susceptibility to gentamycin (CN), tetracycline (T), doxycycline (DO), streptomycin (S), neomycin (N), ciprofloxacin (CIP), Sulphamethoxazole-Trimethoprim (SXT), amoxicillin (AX) and Norofloxacin (NOR) was 88.57%, 22.86%, 51.43%, 56.71%, 22.86%, 51.43%, 48.57%, 28.57% and 71.43%, respectively. While all of the isolates were resistant to ampicillin (AM) and amoxicillin+clavulanic acid (AMC). Conventional polymerase chain reaction for detection of most virulence genes (eaeA, Stx1, LT, cnf1) revealed that two E. coli serotypes O148 and O44 expressed intimin gene and the Stx1 gene, while none of the serotypes expressed LT and cnf1 genes. The finding of virulent multidrug resistant and enterohaemorrhagic E. coli (EHEC) serotypes poses serious health hazard for both rabbits and contact human.

Key words: Rabbits, E. coli, Diarrhea, Serotyping, PCR, Virulence