Environmental Biotechnology Lab., Department of Zoology, Dayalbagh Educational Institute, Agra - 282 005, (UP).
*Corresponding author: Biochemical Genetics Lab, Department of Zoology, Dayalbagh Educational Institute, Dayalbagh, Agra-282005, E-mail: sa_ntprakash@yahoo.co.in
Samples of raw bovine milk and ready-to-eat (RTE) milk products from unorganized sectors in Agra city, India were analyzed seasonally for 1-year to study the occurrence of pathogenic Listeria species. Listeria monocytogenes were detected in 1.69% of milk samples (8/471) and 1.59% of (10/627) milk products on the basis of biochemical characterization, CAMP and DLABN test. Occurrence of L. monocytogenes was seasonal both in milk and milk products with its highest isolation in winter for both milk (P<0.05) and milk products (P<0.01) as compared to summer season. Pathogenicity testing of all the recovered L. monocytogenes isolates revealed that all eight isolates from milk and eight of ten isolates from milk products were pathogenic. The occurrence of pathogenic L. monocytogenes is of concern from public health point of view. The results indicate the necessity to carry out more such studies on Indian dairy products.
