الفهرس 
List of figuresOnly 14 pages are availabe for public view
 |  | from | 170 |  |  |
| | | from | 170 | | |
Abstract
A great concern directed to non-O157 Shiga toxin producing E. coli (STEC) serotypes due to their public health importance. Screening of the existence, antimicrobial profiles, and virulence repertoire of different STEC serotypes from birds, animals essential for human food and human is important. This study aimed to investigate the presence of STEC in different hosts, distribution pattern of Shiga toxin variants eae, and ehxA respectively, and the antimicrobial resistance. A total of 107 samples included 15 chicken fecal samples, 20 ducks fecal samples, 10 cows meat samples, 12 cows milk samples, and 50 human urine samples, respectively, and distributed as follows 7/15 (50%) from chicken, 14/20 (70%) from ducks, 5/10 (50%) from cows meat, 6/12 (50%) from cows milk, and 19/50 (38%) from human urine, there were significant differences between the isolation rates of E.coli from different sources with p < 0.05. All the serotypes 51/51(100%) harbored Stx1, 43/51 (84.3%) contained Stx1d, 41/51 (80.4%) expressed Stx2, 3/51 (5.9%) contained Stx2c, 36/51 (70.6%) harbored Stx2e, 2/51 (3.9%) contained eae, and 39/51 (76.5%) contained ehxA. All the 51 isolates were tested against 13 antimicrobials to detect the most effective types.The resistance to Amikacin, Amoxicillin/ clavulanic acid, Doxycycline, Ampicillin, Nalidixic acid, and Chloramphenicol were listed in ascending manner as follows; 5.9%, 11.8%, 17.6%, 27.5%, 34.1 %, and 50.9%, respectively. While the high resistance to Cephradine, Erythromycin, Norocillin, Oxytetracycline, Clindamycin, Streptomycin, and Penicillin G were listed in ascending manner, (MAR) for each isolate was detected both the serotypes O78 and O91:H21 from ducks and cattle exhibited the highest MAR index 0.92 for each and there found a significant difference between both serotypes and other serotypes with p < 0.05. Screening of the Oxytetracycline resistance genes were done where a total of 41 serotypes exhibited phenotypic resistance to Oxytetracycline, after screening of the Oxytetracycline resistance genes 33/41 (80.5%) of the resistant serotypes harbored tetA, 36/41 (87.8%) harbored tetB, 2/41 (4.9%) contained tetC, 38/41 (92.7%) contained tetE, 22/41 (53.7%) harbored tetG, and none of them harbored tetD. Multiple Locus Variable-number Tandem Repeat Analysis (MLVA) genotyping were performed on (51) isolates there are 26 different genotypes were noticed among the (51) E. coli serotypes. The genotype GT 21 was the highest genotype found among serotypes, Hence, genotyping and antimicrobial resistance are essential epidemiological tools enhancing the control of STEC serotypes.