TY - JOUR
T1 - Antibiotic resistance, phylogenetic grouping and virulence potential of Escherichia coli isolated from the faeces of intensively farmed and free range poultry
AU - Obeng, Akua Serwaah
AU - Rickard, Heather
AU - Ndi, Olasumbo
AU - Sexton, Margaret
AU - Barton, Mary
PY - 2012/1/27
Y1 - 2012/1/27
N2 - Antibiotic use in poultry production is a risk factor for promoting the emergence of resistant Escherichia coli. To ascertain differences in different classes of chickens, the resistance profile, some virulence genes and phylogenetic grouping on 251 E. coli isolates from intensive meat (free range and indoor commercial) and free range egg layer chickens collected between December 2008 and June 2009 in South Australia were performed. Among the 251 strains, 102 (40.6%) and 67 (26.7%) were found to be resistant to tetracycline and ampicillin respectively. Resistance was also observed to trimethoprim-sulfamethoxazole (12.4%), streptomycin (10.8%), spectinomycin (9.6%), neomycin (6.0%) and florfenicol (2.0%) but no resistance was found to ceftiofur, ciprofloxacin or gentamicin. Amplification of DNA of the isolates by polymerase chain reaction revealed the presence of genes that code for resistant determinants: tetracycline (tet(A), tet(B) and tet(C)), ampicillin (bla TEM and bla SHV), trimethoprim (dhfrV and dhfrXIII), sulphonamide (sulI and sulII), neomycin (aph(3)-Ia(aphA1)), and spectinomycin-streptinomycin (aadA2). In addition, 32.3-39.4% of the isolates were found to belong to commensal groups (A and B1) and 11.2-17.1% belonged to the virulent groups (B2 and D). Among the 251 E. coli isolates, 25 (10.0%) carried two or more virulence genes typical of Extraintestinal pathogenic E. coli (ExPEC). Furthermore, 17 of the isolates with multi-resistance were identified to be groups B2 and D. Although no significant difference was observed between isolates from free range and indoor commercial meat chickens (P>0.05), significant differences was observed between the different classes of meat chickens (free range and indoor commercial) and egg layers (P<0.05). While this study assessed the presence of a limited number of virulence genes, our study re emphasises the zoonotic potential of poultry E. coli isolates.
AB - Antibiotic use in poultry production is a risk factor for promoting the emergence of resistant Escherichia coli. To ascertain differences in different classes of chickens, the resistance profile, some virulence genes and phylogenetic grouping on 251 E. coli isolates from intensive meat (free range and indoor commercial) and free range egg layer chickens collected between December 2008 and June 2009 in South Australia were performed. Among the 251 strains, 102 (40.6%) and 67 (26.7%) were found to be resistant to tetracycline and ampicillin respectively. Resistance was also observed to trimethoprim-sulfamethoxazole (12.4%), streptomycin (10.8%), spectinomycin (9.6%), neomycin (6.0%) and florfenicol (2.0%) but no resistance was found to ceftiofur, ciprofloxacin or gentamicin. Amplification of DNA of the isolates by polymerase chain reaction revealed the presence of genes that code for resistant determinants: tetracycline (tet(A), tet(B) and tet(C)), ampicillin (bla TEM and bla SHV), trimethoprim (dhfrV and dhfrXIII), sulphonamide (sulI and sulII), neomycin (aph(3)-Ia(aphA1)), and spectinomycin-streptinomycin (aadA2). In addition, 32.3-39.4% of the isolates were found to belong to commensal groups (A and B1) and 11.2-17.1% belonged to the virulent groups (B2 and D). Among the 251 E. coli isolates, 25 (10.0%) carried two or more virulence genes typical of Extraintestinal pathogenic E. coli (ExPEC). Furthermore, 17 of the isolates with multi-resistance were identified to be groups B2 and D. Although no significant difference was observed between isolates from free range and indoor commercial meat chickens (P>0.05), significant differences was observed between the different classes of meat chickens (free range and indoor commercial) and egg layers (P<0.05). While this study assessed the presence of a limited number of virulence genes, our study re emphasises the zoonotic potential of poultry E. coli isolates.
KW - Escherichia coli
KW - Free range egg layers
KW - Intensive meat chickens
KW - Resistance genes
UR - http://www.scopus.com/inward/record.url?scp=84855955932&partnerID=8YFLogxK
U2 - 10.1016/j.vetmic.2011.07.010
DO - 10.1016/j.vetmic.2011.07.010
M3 - Article
C2 - 21856098
AN - SCOPUS:84855955932
SN - 0378-1135
VL - 154
SP - 305
EP - 315
JO - Veterinary Microbiology
JF - Veterinary Microbiology
IS - 3-4
ER -