title: Beef carcass contamination by Shiga toxin-producing Escherichia coli strains in an abattoir in Brazil: characterization and resistance to antimicrobial drugs.
abstract: A survey was performed to estimate the frequency of Escherichia coli and Shiga toxin-producing E. coli (STEC) in carcasses obtained from an abattoir in Brazil between February 2006 and June 2007. A total of 216 beef carcasses were sampled at three stages of the slaughter process--preevisceration, postevisceration, and postprocessing--during the rain and dry seasons, respectively. Of the carcasses sampled, 58% were preevisceration E. coli positive, 38% were postevisceration positive, and 32% postprocessing positive. At the postprocessing stage, the isolation of E. coli was twice as high in the rain season. E. coli was isolated from 85 carcasses of which only 3 (1.4%) were positive for stx-encoding genes. No E. coli O157 serogroup isolates were detected. No antimicrobial resistance was found in nine of the isolates (10% of the total). The most frequent resistances were seen against cephalothin (78%), streptomycin (38%), nalidixic acid (36%), and tetracycline (30%). Multidrug resistance (MDR) to three or more antimicrobial agents was determined in 28 (33%) E. coli isolates. The presence of STEC and MDR strains among the isolates in the beef carcasses emphasizes the importance of proper handling to prevent carcass contamination.
authors.affiliation: Faculdade de Zootecnia de Dracena, Universidade Estadual Paulista, Ribeirão Preto, Brazil.
authors.forename: Everlon Cid
authors.initials: EC
authors.lastname: Rigobelo
authors.forename: Edilene
authors.initials: E
authors.lastname: Santo
authors.forename: Jose Moacir
authors.initials: JM
authors.lastname: Marin
mesh_terms: D000003:Abattoirs; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001938:Brazil; D002417:Cattle / Q000382:microbiology*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D005506:Food Contamination / Q000032:analysis* / Q000517:prevention & control; D005511:Food Handling / Q000379:methods*; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D012621:Seasons; D012703:Serotyping; D054323:Shiga-Toxigenic Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents