Detection of Mycobacterium avium paratuberculosis in pasteurized milk by PCR according to the search of IS900 gene sequence

Abstract

Background: Mycobacterium avium subsp paratuberculosis (M.a.p) causes chronic intestinal inflammation in dairy cattle and eventually leads to Johne's disease. In some studies, mentioned bacteria has been detected and isolated from milk. As regards, during the milking process; milk could get contaminated with chattels feces,therefore the extent of contamination of milk depends on hygienic methods prior and during of milking and the preparation and delivery to the consumer market processes too.So,the aim of this study was determined the prevalence of mentioned bacteria in pasteurized milk in Ardebil province by PCR method for the first time. Methods: In total; 330 commercially pasteurized milk samples were purchased from various production centers of Ardebil province and 50ml from each sample were centrifuged for M.a.p DNA extraction. Extracted DNA was evaluated for the presence of M.a.p's specific sequence of IS900 by two protocol of PCR assay. Results: M.a.p DNA was detected in 33cases (10% of samples) by assay with F90,F91 primers, 22 cases (6.66% of samples) by assay with FP25, RP26 primers and 11 cases (3.33% of samples) by assay with both pairs primers. Conclusions: The results obtained from this study; demonstrate a relatively high occurrence of M.a.p in pasteurized milk. In addition, regarding the possible etiological role of M.a.p in the development of Crohn’s diseases (Infectious Bowel Disease), it is considered as a serious concern for public health.