Distribution, virulence, genotypic characteristics and antibiotic resistance of Listeria monocytogenes isolated over one-year monitoring from two pig slaughterhouses and processing plants and their fresh hams.

Distribution, virulence, genotypic characteristics and antibiotic resistance of Listeria monocytogenes isolated over one-year monitoring from two pig slaughterhouses and processing plants and their fresh hams. Int J Food Microbiol. 2020 Oct 09;336:108912 Authors: Rugna G, Carra E, Bergamini F, Franzini G, Faccini S, Gattuso A, Morganti M, Baldi D, Naldi S, Serraino A, Piva S, Merialdi G, Giacometti F Abstract Listeria monocytogenes contamination in raw pork and ready to eat foods is an important food safety concern, also for the increasing detection of antimicrobial-resistant isolates. Data on L. monocytogenes occurrence, persistence, distribution and genetic characterization in two different plants, namely in continuum from slaughtered pigs, environment and unfinished products (fresh hams) were observed by one-year monitoring and were integrated with their antimicrobial resistance patterns. A total of 98 samples out of the overall 1131 (8.7%) were positive for L. monocytogenes, respectively 2.6% and 13.2% in plants A and B: only three serotypes were identified, 1/2c (50%), 1/2b (36.7%) and 1/2a (13.27%), and strains were classified in 35 pulsotypes and 16 clusters by PFGE; a unique P-type was highlighted according to the detection of virulence genes. The contamination flow of L. monocytogenes has a low occurrence in slaughterhouse (Plant A = 1.1%, Plant B: 3.1%; p > 0.05) and increased throughout the processing chain with tri...
Source: International Journal of Food Microbiology - Category: Food Science Authors: Tags: Int J Food Microbiol Source Type: research