title: Antimicrobial resistance, virulence determinants and genetic profiles of clinical and nonclinical Enterococcus cecorum from poultry.
abstract: Enterococcus cecorum has been implicated as a possible cause of disease in poultry. However, the characteristics that contribute to pathogenesis of Ent. cecorum in poultry have not been defined. In this study, Ent. cecorum from carcass rinsates (n = 75) and diseased broilers and broiler breeders (n = 30) were compared based upon antimicrobial resistance phenotype, the presence of virulence determinants and genetic relatedness using pulsed-field gel electrophoresis (PFGE). Of the 16 antimicrobials tested, Ent. cecorum from carcass rinsates and clinical cases were resistant to ten and six of the antimicrobials, respectively. The majority of Ent. cecorum from carcass rinsates was resistant to lincomycin (54/75; 72%) and tetracycline (46/75; 61.3%) while the highest level of resistance among clinical Ent. cecorum was to tetracycline (22/30; 73.3%) and erythromycin (11/30; 36.7%). Multidrug resistance (resistance to ≥2 antimicrobials) was identified in Ent. cecorum from carcass rinsates (53/75; 70.7%) and diseased poultry (18/30; 60%). Of the virulence determinants tested, efaAfm was present in almost all of the isolates (104/105; 99%). Using PFGE, the majority of clinical isolates clustered together; however, a few clinical isolates grouped with Ent. cecorum from carcass rinsates. These data suggest that distinguishing the two groups of isolates is difficult based upon the characterization criteria used.
authors.affiliation: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, Russell Research Center, USDA-ARS, Athens, GA, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Jackson
authors.affiliation: Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, Pennsylvania, PA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kariyawasam
authors.affiliation: Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Borst
authors.affiliation: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, Russell Research Center, USDA-ARS, Athens, GA, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Frye
authors.affiliation: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, Russell Research Center, USDA-ARS, Athens, GA, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Barrett
authors.affiliation: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, Russell Research Center, USDA-ARS, Athens, GA, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Hiott
authors.affiliation: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, Russell Research Center, USDA-ARS, Athens, GA, USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Woodley
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002645:Chickens / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D010641:Phenotype; D011201:Poultry Diseases / Q000382:microbiology*; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000032:analysis / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors
keywords: Enterococcus cecorum; antimicrobial resistance; genetic relatedness; poultry; virulence