title: Phenotypic and genotypic characterization of Enterococcus cecorum strains associated with infections in poultry.
abstract: BACKGROUND
  From the beginning of the 21(st) century Enterococcus cecorum has emerged as a significant health problem for poultry raised under intensive production systems. To obtain new insights into this bacterial species, we investigated 82 clinical isolates originating from different poultry flocks in Poland between 2011 and 2014.
  
  
  RESULTS
  Phenotypically, isolates from clinical cases showed ability to growth at low temperatures (4 °C, 10 °C), and differences in growth at 45 °C (74.4 %). Survival at high temperatures (60 °C, 70 °C) was observed for 15, 30 min. More than half of strains survived at 60 °C even after prolonged incubation (1 h), but none survived after 1 h at 70 °C. Total growth inhibition was observed on agar supplemented with tergitol or potassium tellurite. Relatively high number of isolates gave positive reactions for β-galactosidase (βGAL 80 %), Voges Proskauer test (60 %), less for β-mannosidase (17 %), glycogen and mannitol (12 %). The metabolic fingerprinting for E. cecorum obtained in Biolog system revealed ability to metabolise 22 carbon sources. Only 27/82 strains contained ≥ 1 virulence genes of tested 7, however 2.4 % isolates carried 6. Increased antimicrobial resistance was observed to enrofloxacin (87 %), teicoplanin (85 %), doxycycline (83 %), erythromycin (46 %). Most strains (75/82) showed multidrug resistance. The single isolate was resistant to vancomycin (VRE) and high level gentamicin (HLGR). Linezolid resistance among clinical isolates was not found. PFGE revealed diversity of E. cecorum from cases. It could be assumed that transmission of pathogenic strains between flocks regardless of type of production or geographical region may be possible.
  
  
  CONCLUSIONS
  Clinical infections in poultry caused by E. cecorum may indicated on new properties of this bacterial species, previously known as a commensal. Despite many common phenotypic features, differences were found among clinical isolates. Several, widely distributed pathogenic E. cecorum strains seemed to be responsible for infection cases found in different poultry types.
authors.affiliation: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159c St., Warsaw, 02-776, Poland. beata_dolka@sggw.pl.
authors.forename: Beata
authors.initials: B
authors.lastname: Dolka
authors.affiliation: Department of Preclinical Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Ciszewskiego 8 St., Warsaw, 02-786, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Chrobak-Chmiel
authors.affiliation: Department of Microbiology and Infectious Diseases, Faculty of Veterinary Science, Szent István University, Hungária krt. 23-25, Budapest, H-1143, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Makrai
authors.affiliation: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159c St., Warsaw, 02-776, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Szeleszczuk
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D016983:Enterococcus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D010641:Phenotype; D011201:Poultry Diseases / Q000382:microbiology*; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors
keywords: Chicken; Enterococcal spondylitis; Enterococcus cecorum; Genotyping; PFGE; Phenotyping