title: Antibiotic resistance of Enterococcus spp. isolated from wastewater and sludge of poultry slaughterhouses.
abstract: Antibiotimicrobial resistance was investigated in 537 Enterococcus spp. isolates recovered from 22 samples of crude inflow, treated effluent and sludge collected in wastewater treatment plants of eight poultry slaughterhouses of Portugal. No significant differences (P > 0.05) were found in the resistance to each antimicrobial agent with regards to the origin of the sample (inflow, sludge and effluent). Many of the isolates displayed resistance to tetracycline (85.7%), erythromycin (45.7%), nitrofurantoin (34.0%) and rifampicin (17.8%). Resistance was also observed, but to a lesser extent, to ciprofloxacin (10.2%), ampicillin (8.0%), chloramphenicol (4.6%), vancomycin (0.9%) and gentamicin (0.4%). Resistance to three or more antimicrobial classes was present in 37.1% of the isolates. Wastewater treatment resulted in viable enterococci decrease between less than 1 log and 4 log; nevertheless, more than 4.4 x 10(5) colony forming units (CFU)/100 mL were present in the outflow of the plants and thus resistant enterococci are not prevented from reaching the general environment.
authors.affiliation: ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal. paulomartinscosta@mail.telepac.pt
authors.forename: Paulo M
authors.initials: PM
authors.lastname: Martins da Costa
authors.forename: Paulo M
authors.initials: PM
authors.lastname: Vaz-Pires
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Bernardo
mesh_terms: D000003:Abattoirs; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002645:Chickens; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial; D016983:Enterococcus / Q000187:drug effects*; D007220:Industrial Waste; D008826:Microbial Sensitivity Tests; D011174:Portugal; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods; D014871:Water Microbiology
chemical_list: D000900:Anti-Bacterial Agents; D007220:Industrial Waste; D012722:Sewage