Determination of frequency of verotoxigenic Escherichia coli isolated from bovine feces in Kerman

AbstractNowadays, Shiga- like toxin – producing Escherichia coli (STEC), verotoxin – producing E. coli (VTEC), are the most important emerged group of food borne pathogens. Cattle, especially young animals, have been implicated as a principal reservoir of STEC. Foods of bovine origin are the major of the infection. The aim of this study was to genotype the O157 VTEC from bovine feces in Kerman city.A total of 142 cattle’s fecal samples were collected from Kerman’s abattoir. All samples were Grew in m TSB and were plated on chrom agar O157, phenol red agar base with sorbitol, and cultured on differential medium for diagnostic of E. coli. The isolates suspicions to O157 were typed with monoclonal antibody again serotype O157. These isolates and feces samples grown in m TSB, were also tested with M-PCR for detection of stx1, 2 genes. One VTEC O157 (0.7%) carrying stx2 and one non- verotoxigenic E. coli O157 (0.7%) were isolated from feces, also five VTEC strains belong to serotypes other than O157 (3.5%) (two isolates carrying stx1, 2 and three samples carrying stx1 ) were separated from feces which grown in m TSB using d M-PCR. The results of this study showed that the frequency of total of STEC is 3.5% and serotypes other than O157 have higher prevalence. Therefore for the identification of enterohemorrhagic serotypes, bacteriological tests are not satisfactory and molecular tests such as M-PCR are needed for the identification of all serotypes.