Microbiological contamination in three large-scale pig slaughterhouses in Northern Italy

• Main Authors: Pierluigi Di Ciccio, Maria Cristina Ossiprandi, Emanuela Zanardi, Sergio Ghidini, Giancarlo Belluzzi, Alberto Vergara, Adriana Ianieri
• Format: Article
• Language: English
• Published: PAGEPress Publications 2016-11-01
• Series: Italian Journal of Food Safety
• Subjects: Pig slaughterhouse; Pig carcass; Total viable count; Enterobacteriaceae; Salmonella
• Online Access: http://www.pagepressjournals.org/index.php/ijfs/article/view/6151

The aim of this survey was to obtain data on microbiological contamination of pig carcasses and environments in three large-scale Italian slaughterhouses (identified as A-B-C) located in Northern Italy. Each slaughterhouse was visited six times. Five carcasses and three different sites of the slaughterhouse (before and during slaughter) were sampled on each sampling day. A single pooled caecal sample was taken on each sampling day. A total of 90 carcasses, 108 environmental samples and 18 caecal samples were collected. Samples from pig carcasses and slaughterhouse environment were analyzed for total viable count (TVC), <em>Enterobacteriaceae</em> count (EBC) and <em>Salmonella</em>. The caecal contents were examined for <em>Salmonella</em>. Carcasses from slaughterhouse A presented the greatest TVC and EBC mean log value, whereas environmental samples collected during slaughter activities from slaughterhouse C showed the greatest TVC and EBC mean log value. As far as the environmental samples collected before slaughter activities are concerned, an average up to 6 log₁₀ colony forming unit (CFU)/cm² TVC in two slaughter plants (A and C) and 5 log₁₀ CFU/cm² TVC in one slaughter plant (B) was detected. <em>Salmonella</em> was recovered in two slaughterhouses (A and B). Four different <em>Salmonella</em> serotypes were detected in the positive samples (11). Within serotype <em>S.</em> Rissen and <em>S.</em> Typhimurium monophasic-variant isolates, two pulsed-field gel electrophoresis patterns were identified. The findings in this survey suggest that carcass contamination is influenced by the slaughterhouse plant and this could be a result of differences in line speed. The results of environmental sampling have not shown an association with the slaughterhouse plant.