title: Phenotypic and genetic characterization of Salmonella enterica subsp. enterica serovar Typhimurium isolated from pigs in Rio Grande do Sul, Brazil.
abstract: This study aimed to investigate the relatedness of porcine Salmonella enterica subsp. enterica (S.) serovar Typhimurium strains isolated in Southern Brazil. Sixty-six isolates from pigs belonging to three commercial companies were submitted to phage typing, XbaI-macrorestriction (PFGE), IS200 hybridization, rep-PCR, antimicrobial susceptibility testing, and PCR assay targeting the spvR region. All strains presented a unique rep-PCR pattern and 63 strains had a common IS200 profile. One pulse-type (XA) was the most prevalent (39/66 strains) and included strains of phage types DT177, DT192, DT194 and RDNC. The spvR region was detected in three strains, which harboured plasmids of 90 kb. High rates of tetracycline, sulfonamide and streptomycin resistance were found. Isolates from farms located in different geographic regions but associated to the same commercial companies clustered together and presented a common resistance profile. Results suggested that clonal groups of S. Typhimurium are present in pig commercial companies in Southern Brazil.
authors.affiliation: Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, UFRGS, Av. Bento Gonçalves 9090, 90540-000 Porto Alegre, RS, Brazil.
authors.forename: Marjo Cado
authors.initials: MC
authors.lastname: Bessa
authors.forename: Geovana Brenner
authors.initials: GB
authors.lastname: Michael
authors.forename: Nunzia
authors.initials: N
authors.lastname: Canu
authors.forename: Cláudio Wageck
authors.initials: CW
authors.lastname: Canal
authors.forename: Marisa
authors.initials: M
authors.lastname: Cardoso
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Rabsch
authors.forename: Salvatore
authors.initials: S
authors.lastname: Rubino
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001938:Brazil; D024901:Drug Resistance, Multiple, Bacterial; D010802:Phylogeny; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D013552:Swine / Q000382:microbiology*; D013553:Swine Diseases / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents