Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Food Science & Technology, Listeria monocytogenes, Hide, Environment, Carcass, Beef, Slaughterhouse, Persistence, CC9, PROCESSING PLANTS, HIDE CLEANLINESS, PREVALENCE, CARCASSES, MEAT, IDENTIFICATION, CONTAMINATION, TRANSMISSION, RUMINANTS, DIVERSITY, Abattoirs, Animals, Belgium, Cattle, Food Contamination, Food Microbiology, Listeriosis, Molecular Typing, Red Meat, 0702 Animal Production, 0904 Chemical Engineering, 0908 Food Sciences, Dairy & Animal Science, 3003 Animal production, 3006 Food sciences

Abstract:

The introduction, transmission, and persistence of Listeria monocytogenes in Belgian beef slaughterhouses was investigated using genetic characterization. During slaughter, samples were taken of the hide, carcass, and environment to detect the pathogen. Remarkably, L. monocytogenes was massively present on the hide of incoming animals (93%; 112/120), regardless of their visual cleanliness, which implies high contamination pressure levels entering the slaughterhouses. Pathogen transfer via cross-contamination was conclusively confirmed in this study, with the same pulsotypes isolated from the hide, carcass, and environmental samples. Despite the important bacterial presence on the hide of incoming animals, most slaughterhouses succeeded in limiting the transfer as cause of carcass contamination. Persistence along the slaughter line seemed to be a more significant problem, as it was clearly linked to most of the L. monocytogenes positive carcasses. In one slaughterhouse, whole genome sequencing (WGS) revealed that the carcass splitter had contaminated carcasses with the same strain belonging to CC9 for more than one year.