Author(s):
Ferreira, Susana 
; Fraqueza, Maria João ; Queiroz, João ; Domingues, Fernanda ; Oleastro, Mónica
Date: 2012
Persistent ID: http://hdl.handle.net/10400.18/1393
Origin: Repositório Científico do Instituto Nacional de Saúde
Subject(s): Arcobacter spp; Poultry; Antibiotic Resistance; Infecções Gastrointestinais
Description
The genus Arcobacter is an emerging pathogen associated with several clinical symptoms, namely diarrhoea,
abdominal pain or bacteraemia. This genus is widely distributed and has been isolated from environmental,
animal, food and human samples, being poultry considered the major reservoir.
In this study, forty three Arcobacter butzleri strains were isolated from poultry of three flocks from different
farms and environment samples at a Portuguese slaughterhouse, also three reference strains were included. All
isolates were confirmed at species level by multiplex PCR and genomic DNA fingerprints of all isolates were
determined using Pulsed Field Gel Electrophoresis (PFGE) after enzymatic digestion with SmaI and the isolates
with undistinguishable SmaI patterns were further analyzed with a second restriction enzyme, SacII.
Phenotypic resistance profiles to nine antibiotics were assessed by broth microdilution method. Biofilm
formation assays were performed in the 36 out of the 43 A. butzleri isolates, either presenting different pulsetypes
or similar PFGE patterns but different origin or even different resistance patterns.
PFGE patterns obtained using restriction enzymes SmaI and SacII revealed genetic diversity, with 32 distinct
PFGE patterns. A high percentage of A. butzleri isolates was found to be resistant, recording four different
resistance profiles. Twenty four of the 43 isolates presented a phenotypic resistance to ciprofloxacin, in contrast
to the great susceptibility against gentamicin and chloramphenicol. Among the 36 selected A. butzleri isolates,
13.9% were categorized as moderately adherent, while 58.3% were defined as weakly adherent.
Overall, the results showed a high degree of genetic heterogeneity among A. butzleri isolates, along with high
levels of resistance to several antibiotics. Biofilm formation ability of A. butzleri can possibly favour dispersion
and cross-contamination along the slaughterhouse processing line. These findings may represent a contribution to
get insight the survival and even persistence mechanisms of this organism in the environment and on its
relevance as a potential hazard for foodborne infections.
