الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Cheese is considered an important easily digested food and play an important role in the survival and transport of pathogenic bacteria including E. coli, S.aureus, B.cereus and Salmonella spp. This study was performed to determine the existence of E. coli, S.aureus, B.cereus and Salmonella spp. in locally produced cheese such as Kareish, Tallaga and Damietta cheese. As, a total of 105 cheese samples (35 of each Kareish, Tallaga and Damietta cheese) obtained from different dairy shops located at El Menofia and El Gharbia governorates. Cheese samples were tested for isolation and identification of E.coli ,S.aureus, B.cereus and Salmonella spp.. Furthermore, E. coli and S.aureus strains were tested for their antibiotic susceptibility and detection of the virulence gene of S.aureus, B.cereus and Salmonella spp. The incidence of E. coli was (37.1%) and (2.8%) in Kareish and Damietta cheese samples, respectively and couldn’t detected in Tallaga cheese samples. There are nine different E. coli serovars were identified namely, O26:H11 (4), O111:H2, O124, O163:H2, O114, O125:H21 (2), O1 (2), O15 and one untyped strain. Also this study shows that E.coli is the most resistant to Erythromycin (E) with percentage of 100% and it is most susceptible to Gentamicin (G) in percentage of 77.8%. Also S.aureus was isolated in the rate of 42.85%, 5.71% and 8.5% in the Kareish cheese, Damietta cheese and Tallaga cheese, respectively and the isolates was submitted for enterotoxin genes detection by PCR. Also the antibiograme of S.aureus showed that S.aureus was most resistant to Kanamycin (K) and Neomycin (N) with percentage of (100%).The incidence rate of B.cereus was 2.8%, 14.28% and 5.71%, respectively and the isolated strains submitted for detection of their virulence genes. While in this study, one strain of Salmonella spp. was isolated which was identified as S.Teseive group B from Tallaga cheese samples and couldn’t be detected in Kareish or Damietta cheese and the isolated strain was positive for invA and hilA genes specific for Salmonella spp.
Conclusively, cheese can be considered as a serious source of pathogenic bacteria therefore, proper management practices and effective control measures are recommended to improve the hygiene and sanitation of milk and milk products.