Validation of an open-formula, diagnostic real-time PCR method for 20-h detection of Salmonella in animal feeds
2012 (English)In: Veterinary Microbiology, ISSN 0378-1135, E-ISSN 1873-2542, Vol. 158, no 3-4, p. 431-435Article in journal (Refereed) Published
Abstract [en]
A comparative study of a 20-h, non-commercial, open-formula PCR method and the standard culture-based method NMKL 187, for detection of Salmonella, was performed according to the validation protocol from the Nordic organisation for validation of alternative microbiological methods (NordVal) on 81 artificially or naturally contaminated animal feed samples. The PCR method is based on culture enrichment in buffered peptone water for 16 ± 2. h followed by a magnetic beads based semi automated DNA extraction and real-time PCR analysis, including an internal amplification control. The limit of detection (LOD50) was found to be 7.19 and 7.24. CFU/sample for the PCR method and NMKL187, respectively. A very good correlation between results obtained by the two methods was found (Cohen's kappa = 0.92). The relative accuracy, relative sensitivity and relative specificity were found to be 97.5%, 102.0% and 96.6%, respectively. This method is the fastest open PCR based analysis protocol for detection of Salmonella in feed samples. Implementing rapid methods such as the one validated in this study can speed up Salmonella testing of feed for food-producing animals. © 2012 Elsevier B.V.
Place, publisher, year, edition, pages
2012. Vol. 158, no 3-4, p. 431-435
Keywords [en]
Animal feed, Detection, Food safety, Molecular methods, NordVal, PCR, Polymerase chain reaction, Salmonella, Validation, peptone, animal food, animal salmonellosis, article, automation, bacterium contamination, bacterium culture, bacterium detection, colony forming unit, comparative study, diagnostic test, DNA extraction, enrichment culture, food contamination, gene amplification, limit of detection, nonhuman, real time polymerase chain reaction, sensitivity and specificity, validation process, Animals, Food Microbiology, Real-Time Polymerase Chain Reaction, Time Factors, Animalia
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-39019DOI: 10.1016/j.vetmic.2012.02.026Scopus ID: 2-s2.0-84862555563OAI: oai:DiVA.org:ri-39019DiVA, id: diva2:1324804
Note
Funding details: European Commission, 036272; Funding text 1: Kirsten Michaëlis and Pia Engelsmann are acknowledged for excellent technical assistance. Feed samples were obtained from the National Veterinary Institute (SVA), Uppsala, Sweden and Svenska Foder, Lidköping, Sweden. Salmonella strains were kindly provided by SVA. This study was financially supported in part by the European Union funded Integrated Project BIOTRACER (contract 036272) under the 6th RTD Framework. The funders had no role in study design, data collection and analysis, conclusions, decision to publish, or preparation of the manuscript.
2019-06-142019-06-142019-06-14Bibliographically approved