مطالعه ميزان آلودگي شيرهاي خام استان چهارمحال بختياري به باكتري اشريشياكلي :7510H7

Study on the Contamination of raw milk with E. coli Oi57: H7 in Chaharmahal - Bakhtiari province.

Coliform bacteria are important group of bacteria associated with foods. Among the bacteria of this group, E. coli is studied because of its pathogenesis and prevalence in many kinds of foods. Recently one serotype of this microorganism (Oʹ757:7/7) is considered as a foodborne pathogen by the most food safety researchers and organizations. This serotype is associated with hemorrhagic colitis and hemolytic uremic syndrom (HUS) in human. This study was conducted to determine the contamination of raw milk with E. coli Oi5?:H7 in Chaharmahal - Bakhtiari province. Two hundred samples of raw milk were collected from different parts of the province; bacteriological examination were done by using Escherichia Broth (ed, Novobiocin) as an enrichment media and then MC concky Sorbitol as a selective plating media. Suspected colonies were checked by IMViC tests and serological examinations were done to confirm the E. coli OisjiHj. In bacteriological examinations, 83 suspected colonies were isolated. Serological tests with O and H antisera showed that 9 (4.5%) of the isolates were O/57 and none of them was Oi57iHj, Indeed 22 serotypes of E. coli other than O157 were isolated from the samples. The results of this study showed that the samples collected from the west of the province were shown the most (7.14%) and the north were shown the least (3.61%) contamination with E. coli.