This research work was conducted as well as the determination of the resistance to antibiotics of these isolated species of E. coli in Nineveh governorate to assess the incidence of Escherichia coli (E. coli) contamination in different fish farms and local fish markets. The total number of fish samples used in the present study was 153, including 75 samples from various fish farms and 78 samples from different local markets in Mosul. The current study showed that the percentage of E. coli isolated from fish farms was 24% (18/75) and 35.9% (28/78) from local markets. While it showed a positive result for E. coli with serotype (O157:H7) with a percentage was 9.3 and 14.1% from both farmed fish and market fish samples, respectively. Additionally, all E. coli positive isolates possess the specific uidA gene, which was detected using the PCR technique. The highest sensitivity of E. coli bacteria to the antibiotic's ciprofloxacin, trimethoprim, and gentamicin was 96, 94, and 86%, respectively. At the same time, the highest percentage of resistance of E. coli to the antibiotics cephalothin, tetracycline, erythromycin, and amoxicillin was 100, 64, 64, and 62%, respectively. To reduce health risks to consumers, these results provide useful basic information for the proper management of these environments in order to prevent fecal contamination in fish farms and the fish sold in local markets.

The aim of the current study is to detect the presence of some virulence genes of Escherichia (E.) coli in fish. A total of 46 strains of E. coli were previously isolated from 153 fish samples, including 28 and 18 isolate of E. coli from local markets and fish farms, respectively, in Nineveh Governorate from November 2021 to January 2022. The results of the study show that all isolates of E. coli possessed the uidA gene with a molecular weight of 623 bp. In addition, they show that 88.9% (16/18) isolates from farmed fish samples possessed the Stx1 gene with a molecular weight of 347 bp, while 72.2% (13/18) of them carried the Stx2 gene with a molecular weight of 589 bp. Also, the study unveils that 89.3 % (25/28) isolated from the market fish samples possessed the Stx1 gene with a molecular weight of 347 bp and 85.7% (24/28) isolates carried the Stx2 gene with a molecular weight of 589 bp. The rfb gene is not detected in this study, neither in farm fish nor in the samples from the local fish markets using the PCR technique. Likewise, it shows that E. coli isolated from fish possessed the Stx1 and Stx2 genes, which are major causative agents of food poisoning for consumers. Finally, the study gives important information about the application of health conditions on fish farms and fish markets to prevent contamination and reduce infections by foodborne pathogens that cause food poisoning for humans.

No abstract