Prevalence and Characterization of Escherichia coli in Raw Milk and Some Dairy Products at Mansoura City

Abstract

The present study aimed to detect the prevalence and antibiotic sensitivity pattern of Escherichia coli in raw milk and some dairy products (white soft cheese, yoghurt, and Laban rayeb) in Mansoura city, Egypt. A total of 200 samples, obtained equally from raw milk (farm and market milk), white soft cheese (Kareish and Domiati), yoghurt (small scale and large scale), and Laban rayeb (small scale and large scale) were examined for the presence of E. coli by using eosin methylene blue agar (EMB). Suspected E. coli isolates were confirmed by biochemical tests and then selected numbers of E. coli strains were identified serologically. Furthermore, serologically identified strains were subjected to antibiotic sensitivity testing. In total, the prevalence of E. coli recovered from the examined raw milk and dairy products samples was 28% (56/200). The highest prevalence was detected in raw market milk (52%), followed by Kareish cheese (48%) while, the lowest prevalence was obtained in large-scale yoghurt and large-scale Laban rayeb samples (8%). The selected numbers of E. coli strains subjected to serologic examination showed variable somatic and H antigens. About 58.8% of E. coli strains showed multi-antibiotic resistance (MAR) criteria at least to one antimicrobial in three different classes of antibiotics. The highest resistance was obtained from erythromycin (100%) then oxacillin (94%), cefepime (82%), penicillin G (76.5%), and ampicillin (58.5%), nalidixic acid (52.9%) and cefazolin (47.1%). the obtained results show the great hazard proposed to public health, therefore, the application of hygienic measures in all practices concerning dairy industry from farm to fork is not just advice but a necessity to maintain human health.