Some studies on the occurrence of yersinia microorganisms in raw milk and some soft cheeses sold in alexandria governorate

Document Type : Research article

Authors

Dept. of Microbiology, Animal Health Research Institute, Alexandria Branch.

Abstract

A total of 150 samples including 50 samples of raw milk, 50 samples of Kareish cheese and 50 samples of Damietta cheese, all were collected randomly from Alexandria markets and street vendors and examined
bacteriologically for the detection and identification of existing Yersinias. The result recorded in this investigation declared the Yersinia species could be isolated from raw milk, Kareish ch Damietta cheese in percentages of 20, 14, and 6% respectively. Yersian enterocolitica which is pathogenic for human as it is responsible for food poisoning and other gastrointestinal symptoms was isolated from raw milk in 6 cases (12%), from Kareish cheese in 3 isolates (6%) and could not be isolated from Damietta cheese. The presence of Yersinias in this study reflected the lack of hygienic supervision and poorly cleaned and sanitized dairy farm equipments and processing plant equipments. Moreover, Yersinia enterocolitica isolated in this study was tested for susceptibility to 10 antimicrobial drugs. All isolates were highly susceptable to Chloramphinicol, Sulphamethoxazole, Tetracyclin, and Streptomycin but resistant to Ampicillin, Neomycin, and Norfloxacin. The public health hazard of Yersinia enterocolitca with other Yersinia species and the sanitary measures for improving milk quality beside proper handling and distribution of milk and milk products must be done under the most possible hygienic conditions.

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