title: Antimicrobial resistance of Salmonella serotypes isolated from slaughter-age pigs and environmental samples.
abstract: The aim of this study was to determine the antimicrobial resistance patterns of Salmonella strains isolated from slaughter-age pigs and environmental samples collected at modern swine raising facilities in Brazil. Seventeen isolates of six serotypes of Salmonella enterica subsp. enterica were isolated out of 1,026 collected samples: Salmonella Typhimurium (1), Salmonella Agona (5), Salmonella Sandiego (5), Salmonella Rissen (1), Salmonella Senftenberg (4), and Salmonella Javiana (1). Resistance patterns were determined to extended-spectrum penicillin (ampicillin), broad-spectrum cephalosporins (cefotaxime and ceftriaxone), aminoglycosides (streptomycin, neomycin, gentamicin, amikacin, and tobramycin), narrow-spectrum quinolone (nalidixic acid), broad-spectrum quinolone (ciprofloxacin and norfloxacin), tetracycline, trimethoprim, and chloramphenicol. Antimicrobial resistance patterns varied among serotypes, but isolates from a single serotype consistently showed the same resistance profile. All isolates were resistant to tetracycline, streptomycin, and nalidixic acid. One isolate, Salmonella Rissen, was also resistant to cefotaxime and tobramycin. All serotypes were susceptible to ceftriaxone, norfloxacin, ciprofloxacin, ampicillin, gentamicin, and chloramphenicol. The high resistance to tetracycline and streptomycin may be linked to their common use as therapeutic drugs on the tested farms. No relation was seen between nalidixic acid and fluoroquinolone resistance.
authors.affiliation: Departamento de Patologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Unesp campus de Jaboticabal, 14 884-900, Jaboticabal, SP, Brasil.
authors.forename: Celso José Bruno
authors.initials: CJ
authors.lastname: Oliveira
authors.forename: Luiz Fernando Oliveira Silva
authors.initials: LF
authors.lastname: Carvalho
authors.forename: Sueli Aparecida
authors.initials: SA
authors.lastname: Fernandes
authors.forename: Ana Terezinha
authors.initials: AT
authors.lastname: Tavechio
authors.forename: Claudio Camacho Pereira
authors.initials: CC
authors.lastname: Menezes
authors.forename: Francisco José
authors.initials: FJ
authors.lastname: Domingues
mesh_terms: D000821:Animal Feed / Q000382:microbiology; D000818:Animals; D001938:Brazil; D024881:Drug Resistance, Bacterial; D004777:Environment; D005243:Feces / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D012007:Rectum / Q000382:microbiology; D012475:Salmonella / Q000187:drug effects*; D012703:Serotyping; D012722:Sewage / Q000382:microbiology; D013552:Swine / Q000382:microbiology*; D014881:Water Supply
chemical_list: D012722:Sewage