Giuliana Siddi, Francesca Piras, Maria Pina Meloni, Mattia Migoni, Mario Cuccu, Fabrizio Simbula, Eleonora Serra, Luigi Crobu, Myriam Casula, Fabiana Manca, Alessio Sau, Pernille Gymoese, Maria Fredriksson-Ahomaa, Enrico Pietro Luigi De Santis, Christian Scarano
{"title":"<i>Salmonella</i> and <i>Yersinia enterocolitica</i> through the pig meat chain in Sardinia: occurrence, antimicrobial resistance and genetic insight.","authors":"Giuliana Siddi, Francesca Piras, Maria Pina Meloni, Mattia Migoni, Mario Cuccu, Fabrizio Simbula, Eleonora Serra, Luigi Crobu, Myriam Casula, Fabiana Manca, Alessio Sau, Pernille Gymoese, Maria Fredriksson-Ahomaa, Enrico Pietro Luigi De Santis, Christian Scarano","doi":"10.4081/ijfs.2024.13199","DOIUrl":null,"url":null,"abstract":"<p><p>This study aimed to characterize Salmonella and Yersinia enterocolitica detected in fattening pigs in Sardinia, examining genetic similarity and antimicrobial resistance of isolates from farms and slaughterhouses and evaluating carcass hygiene. Environmental samples were collected from six pig farms, and the same pigs were also sampled at the slaughterhouses. Palatine tonsils, mesenteric lymph nodes, colon content, and carcass surface samples were collected and tested for Salmonella and Y. enterocolitica. Antimicrobial resistance testing and whole genome sequencing were performed on all isolates. Carcass surface samples were tested for total aerobic colony count (ACC) and Enterobacteriaceae count (EBC). Y. enterocolitica was found in two farms (33%), while Salmonella was absent in environmental farm samples. At slaughterhouses, 13.1% of pigs were found positive for Salmonella (lymph nodes, colon content, and palatine tonsils samples), but Y. enterocolitica was not detected. Salmonella isolates were typed as monophasic S. Typhimurium ST34 and S. Goldcoast ST358, with few allelic differences among isolates of the same ST. Salmonella ST34 showed resistance towards ampicillin, streptomycin, sulfonamide, and tetracycline (blaTEM-1B, aph(3 )-Ib, sul2 and tetB genes, R-type ASSuT). Y. enterocolitica isolates (biotype 2, ST853, and ST859) showed resistance to ampicillin and amoxicillin-clavulanic acid (blaA gene). Process hygiene criteria were generally met, with mean (log10 CFU/cm2 ± standard deviation) values for ACC and EBC being 2.23±0.74 and 0.75±0.81. Pigs of Sardinia are confirmed carriers of Salmonella and Y. enterocolitica, but overall hygienic status in farms and slaughterhouses in Sardinia is acceptable. Monophasic S. Typhimurium and Y. enterocolitica isolates showed typical resistance patterns. Monophasic S. Typhimurium ST34 isolates with R-type ASSuT are confirmed as epidemic clones.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":"14 1","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11816032/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Italian Journal of Food Safety","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.4081/ijfs.2024.13199","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"FOOD SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study aimed to characterize Salmonella and Yersinia enterocolitica detected in fattening pigs in Sardinia, examining genetic similarity and antimicrobial resistance of isolates from farms and slaughterhouses and evaluating carcass hygiene. Environmental samples were collected from six pig farms, and the same pigs were also sampled at the slaughterhouses. Palatine tonsils, mesenteric lymph nodes, colon content, and carcass surface samples were collected and tested for Salmonella and Y. enterocolitica. Antimicrobial resistance testing and whole genome sequencing were performed on all isolates. Carcass surface samples were tested for total aerobic colony count (ACC) and Enterobacteriaceae count (EBC). Y. enterocolitica was found in two farms (33%), while Salmonella was absent in environmental farm samples. At slaughterhouses, 13.1% of pigs were found positive for Salmonella (lymph nodes, colon content, and palatine tonsils samples), but Y. enterocolitica was not detected. Salmonella isolates were typed as monophasic S. Typhimurium ST34 and S. Goldcoast ST358, with few allelic differences among isolates of the same ST. Salmonella ST34 showed resistance towards ampicillin, streptomycin, sulfonamide, and tetracycline (blaTEM-1B, aph(3 )-Ib, sul2 and tetB genes, R-type ASSuT). Y. enterocolitica isolates (biotype 2, ST853, and ST859) showed resistance to ampicillin and amoxicillin-clavulanic acid (blaA gene). Process hygiene criteria were generally met, with mean (log10 CFU/cm2 ± standard deviation) values for ACC and EBC being 2.23±0.74 and 0.75±0.81. Pigs of Sardinia are confirmed carriers of Salmonella and Y. enterocolitica, but overall hygienic status in farms and slaughterhouses in Sardinia is acceptable. Monophasic S. Typhimurium and Y. enterocolitica isolates showed typical resistance patterns. Monophasic S. Typhimurium ST34 isolates with R-type ASSuT are confirmed as epidemic clones.
期刊介绍:
The Journal of Food Safety (IJFS) is the official journal of the Italian Association of Veterinary Food Hygienists (AIVI). The Journal addresses veterinary food hygienists, specialists in the food industry and experts offering technical support and advice on food of animal origin. The Journal of Food Safety publishes original research papers concerning food safety and hygiene, animal health, zoonoses and food safety, food safety economics. Reviews, editorials, technical reports, brief notes, conference proceedings, letters to the Editor, book reviews are also welcome. Every article published in the Journal will be peer-reviewed by experts in the field and selected by members of the editorial board. The publication of manuscripts is subject to the approval of the Editor who has knowledge of the field discussed in the manuscript in accordance with the principles of Peer Review; referees will be selected from the Editorial Board or among qualified scientists of the international scientific community. Articles must be written in English and must adhere to the guidelines and details contained in the Instructions to Authors.