title: Rapid testing and quantification of Salmonella in ileocaecal lymph nodes of Austrian pigs slaughtered for consumption.
abstract: Traditionally, quantitative microbial risk assessment (QMRA) is based on culture-dependent technologies. However, molecular quantification could forge additional, detailed information. A prerequisite of quantitative real-time PCR in animal science is a tissue preparation method where large volumes of tissue material can be reduced and particularly target cells can be concentrated. An easy-to-use sample preparation method for food (Matrix-Lysis) was recently adapted to tissues and now permits quantification of target cells from up to 5 g of organic matrix. The aim of this study was to examine the suitability of Matrix-Lysis for quantification of Salmonella in porcine ileocaecal lymph nodes (ICLNs). After demonstrating constant recovery rates, ICLNs from 540 pigs were examined for Salmonella spp. with Matrix-Lysis. Samples were also analysed using ISO 6579:2002, a combined enrichment/qPCR method and a lateral flow test. It could be shown that qPCR coupled with Matrix-Lysis can contribute to QMRA in food safety by enabling reproducible quantitative data, even at low contamination rates.
authors.affiliation: Institute of Milk Hygiene, Milk Technology and Food Science, Department of Veterinary Public Health and Food Science, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Mann
authors.affiliation: Institute of Milk Hygiene, Milk Technology and Food Science, Department of Veterinary Public Health and Food Science, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Wagner
authors.affiliation: Austrian Agency for Health and Food Safety (AGES), Institute for Veterinary Disease Control Mödling, Robert Koch Gasse 17, 2340 Mödling, Austria.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Schmoll
authors.affiliation: Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Slaghuis
authors.affiliation: Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Schönenbrücher
authors.affiliation: Christian Doppler Laboratory for Molecular Food Analytics, Department of Veterinary Public Health and Food Science, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria. Electronic address: Patrick-Julian.Mester@vetmeduni.ac.at.
authors.forename: Patrick
authors.initials: P
authors.lastname: Mester
mesh_terms: D000818:Animals; D001317:Austria / Q000453:epidemiology; D004269:DNA, Bacterial / Q000235:genetics; D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology / Q000379:methods*; D064088:Hazard Analysis and Critical Control Points / Q000379:methods; D007080:Ileocecal Valve / Q000382:microbiology; D008198:Lymph Nodes / Q000382:microbiology*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods* / Q000662:veterinary*; D018570:Risk Assessment / Q000379:methods; D012475:Salmonella / Q000235:genetics / Q000302:isolation & purification*; D012481:Salmonella Infections, Animal / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D013552:Swine / Q000382:microbiology*; D013553:Swine Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial
keywords: Matrix-Lysis; Pig; QMRA; Quantification; Salmonella