Detection of Mycobacterium avium subspecies paratuberculosis genetic components in retail cheese curds purchased in Wisconsin and Minnesota by PCR

• DOI: 10.1016/j.mcp.2005.12.006
• Publication Date: 2006-03-21T12:15:54Z
• Authors: Dorn L. Clark Jr.; Jennifer L. Anderson; Jeff J. Koziczkowski; Jay L.E. Ellingson
• Keywords: DNA, Bacterial; 0301 basic medicine; 2. Zero hunger; Minnesota; Colony Count, Microbial; Sterilization; Food Contamination; Polymerase Chain Reaction; Mycobacterium avium subsp. paratuberculosis; 03 medical and health sciences; Wisconsin; Cheese; Food Microbiology; Animals; Cattle; DNA Primers

Research has been focused on the detection of Mycobacterium avium subspecies paratuberculosis (MAP) in pasteurized milk; however, pasteurized milk is a key ingredient in a variety of food products. Therefore, MAP contamination in milk-derived products must be investigated. We undertook a six-month study to investigate the presence of viable MAP and MAP genetic components in cheese curds purchased from retail outlets in the northern and southern regions of Wisconsin and Minnesota. A total of 98 retail cheese curd samples were tested for MAP by PCR prescreen, culture on Herrold's egg yolk agar slants with mycobactin J and amphoteracin B, naladixic acid, and vancomycin, and slant rinse PCR using IS900 and hspX primer sets. Although no viable MAP were able to be cultured, 5% of the samples were PCR positive with both the IS900 and hspX primer sets (MAP-specific DNA) when prescreened and 1% of the samples were PCR positive with both the IS900 and hspX primer sets when culture slants were rinsed and tested.