Prevalence and fingerprinting of Listeria monocytogenes strains isolated from raw whole milk in farm bulk tanks and in dairy plant receiving tanks

Results show that Listeria Monocytogenes is detected in 1.0% of the 294 farm bulk tanks tested, whereas the contamination level is 19.6% in the milk from the silo receiving tanks at a Swedish dairy plant. Molecular analysis indicates that out of 65 isolates of L. monocytogenes, 16 different clonal types are identified, while the dairy silo milk showed five clonal types.