title: Prevalence and Diversity of Salmonella Serotypes in Ecuadorian Broilers at Slaughter Age.
abstract: Salmonella is frequently found in poultry and represent an important source for human gastrointestinal infections worldwide. The aim of this study was to investigate the prevalence, genotypes and antimicrobial resistance of Salmonella serotypes in broilers from Ecuador. Caeca content from 388 at random selected broiler batches were collected in 6 slaughterhouses during 1 year and analyzed by the ISO 6579/Amd1 protocol for the isolation for Salmonella. Isolates were serotyped and genotypic variation was acceded by pulsed field gel electrophoresis. MIC values for sulfamethoxazole, gentamicin, ciprofloxacin, ampicillin, cefotaxime, ceftazidime, tetracycline, streptomycin, trimethropim, chloramphenicol, colistin, florfenicol, kanamycin and nalidixic acid were obtained. Presence of blaCTX-M, blaTEM, blaSHV and blaCMY; and mcr-1 plasmid genes was investigated in resistant strains to cefotaxime and colistin respectively. Prevalence at batch level was 16.0%. The most common serotype was S. Infantis (83.9%) followed by S. Enteritidis (14.5%) and S. Corvallis (1.6%). The pulsed field gel electrophoresis analysis showed that S. Corvallis, S. Enteritidis and S. Infantis isolates belonged to 1, 2 and 12 genotypes respectively. S. Infantis isolates showed high resistance rates to 12 antibiotics ranging from 57.7% (kanamycin) up to 98.1% (nalidixic acid and sulfamethoxazole). All S. Enteritidis isolates showed resistance to colistin. High multiresistant patterns were found for all the serotypes. The blaCTX-M gene was present in 33 S. Infantis isolates while mcr-1 was negative in 10 colistin resistant isolates. This study provides the first set of scientific data on prevalence and multidrug-resistant Salmonella coming from commercial poultry in Ecuador.
authors.affiliation: Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador.
authors.forename: Christian
authors.identifier: http://orcid.org/0000-0002-4893-502X
authors.initials: C
authors.lastname: Vinueza-Burgos
authors.affiliation: Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador.
authors.forename: María
authors.initials: M
authors.lastname: Cevallos
authors.affiliation: Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador.|Centro Internacional de Zoonosis, Quito, Ecuador.
authors.forename: Lenin
authors.initials: L
authors.lastname: Ron-Garrido
authors.affiliation: National Reference Centre for Salmonella and Shigella, Bacterial Diseases Division, Communicable and Infectious Diseases, Scientific Institute of Public Health (WIV-ISP), Brussels, Belgium.
authors.forename: Sophie
authors.initials: S
authors.lastname: Bertrand
authors.affiliation: Department of Veterinary Public Health and Food Safety, Faculty of Veterinary, Ghent University, Merelbeke, Belgium.
authors.forename: Lieven
authors.initials: L
authors.lastname: De Zutter
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002645:Chickens / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D004484:Ecuador / Q000453:epidemiology; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D005838:Genotype; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D011201:Poultry Diseases / Q000453:epidemiology* / Q000382:microbiology; D015995:Prevalence; D012475:Salmonella / Q000187:drug effects / Q000235:genetics*; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D012477:Salmonella enteritidis / Q000235:genetics; D012703:Serotyping
chemical_list: D000900:Anti-Bacterial Agents