Molecular detection of E.coli O157

Abstract

This study was based on the importance of the pathogens that cause diarrhea in sheep and their impact on livestock, E.coli O157:H7 which are considered one of the most important pathogens, were studied and isolated with sensitivity test during the period (October 2021 to December 2021), samples were taken from infected sheep in fields around Baghdad (Abu-ghraib , AL-mahmoudia and AL-yosifiya ), All samples were cultured on MacConkey agar , Eosine Methylene Blue and Sorbitol MacConkey agar for E.coli isolation according the isolates were identified by biochemical tests.out of 101 diarrhea samples, 100 isolates gave positive E.coli results and was taken three isolates appeared more resistance to antibiotics , and one isolate very sensitive to antibiotics. These isolates were selected to be confirmed by using molecular detection PCR. Among the three isolates most resistant to antibiotics showed a molecular diagnosis two belonging to the E.coli O157-H7 , in addition to the isolate most sensitive to antibiotics , which gave a positive E.coli O157-H7 result, but isolates are more resistance antibiotics appeared similar to the result of isolate appear more sensitive antibiotics because bacteria can evolve rapidly to adapt to environmental change., this evolution can turn harmless bacteria into harmful bacteria.