Campylobacter jejuni is a major cause of food-borne diarrhea in many countries. In this study a total number of 200 bulk tank milk samples which were delivered to Pegah pasteurization factory in Mashhad were randomly collected, in consecutive days during summer. The presence of Campylobacter genus and serovar Campylobacter jejuni in collected samples were assessed by performing the enrichment followed by streaking on selective media. The suspected colonies were isolated on sheep blood agar and tested for morphology, motility, gram staining, biochemical properties and hippurate hydrolysis activity. For comparison, a multiplex PCR assay (m-PCR) from suspected colonies with two sets of primers was employed for concurrent identification of Campylobacter genus and its jejuni serovar. By conventional culture method including hippurate hydrolysis test from suspected colonies, 12.5% of samples were determined as positive, but in m-PCR assay 8% of cultures harvest, identified as C. jejuni. It seems that conventional method, based on hippurate hydrolysis for detection of C. jejuni, could not be a reliable test. The use of m-PCR method based on amplification from conserved genes, allows reliable detection and identification of C. jejuni.

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