TY - JOUR
T1 - Rapid identification of virulence genes in enterotoxigenic Escherichia coli isolates associated with diarrhoea in Queensland piggeries
AU - Do, T.
AU - Stephens, C.
AU - Townsend, K.
AU - Wu, X.
AU - Chapman, T.
AU - Chin, J.
AU - McCormick, B.
AU - Bara, M.
AU - Trott, D. J.
PY - 2005
Y1 - 2005
N2 - Objective: To identify virulence genes in enterotoxigenic E coli (ETEC) isolates associated with diarrhoea in neonatal, 1 to 3 week-old and weaned pigs in south east Queensland. Design: Multiplex PCR and serotyping were applied to E coli isolates obtained over a 5-year period (1998-2002) from cases diagnosed at Toowoomba Veterinary Laboratory. Procedure: A total of 126 isolates from 25 different Queensland piggeries were tested for haemolytic activity on 5% sheep blood agar and by multiplex PCR for the presence of five commonly recognised fimbrial (F4, F5, F6, F41 and F18) and three enterotoxin genes (STa, STb, LT). A subset of 62 representative isolates were serotyped by slide agglutination. For comparative purposes, multiplex PCR was also performed on the DNA of 31 ETEC isolates from 9 serotypes originating from piggeries in southern New South Wales. Results: A total of 113 (89.7%) of the isolates from Queensland possessed ETEC virulence genes, including 14 of 15 isolates from neonatal pigs (93.3%), 18 of 23 isolates from 1 to 3 week old pigs (78.3%) and 81 of 88 isolates from weaned pigs (92.1%). F4:STa:STb:LT (serotype O149) was the most prevalent pathotype in neonatal and 1-3 week old pigs and F4:STa:STb:LT (serotype O149) and F18:STa:STb:LT (serotype O141) were most prevalent in weaned pigs. In comparison, isolates obtained from neonatal pigs from New South Wales belonged to a more diverse range of pathotypes and serotypes. Conclusion: Multiplex PCR was a rapid and specific method for detecting the presence of ETEC virulence genes in porcine E coli isolates. For isolates obtained from cases of suspected colibacillosis in Queensland, growth of a heavy pure culture of haemolytic E coli was a sensitive prognostic indicator of the presence of ETEC virulence genes in the isolate. ETEC pathotypes and serotypes remained stable in Queensland piggeries over the five-year study period and appear to have changed little over the last three decades.
AB - Objective: To identify virulence genes in enterotoxigenic E coli (ETEC) isolates associated with diarrhoea in neonatal, 1 to 3 week-old and weaned pigs in south east Queensland. Design: Multiplex PCR and serotyping were applied to E coli isolates obtained over a 5-year period (1998-2002) from cases diagnosed at Toowoomba Veterinary Laboratory. Procedure: A total of 126 isolates from 25 different Queensland piggeries were tested for haemolytic activity on 5% sheep blood agar and by multiplex PCR for the presence of five commonly recognised fimbrial (F4, F5, F6, F41 and F18) and three enterotoxin genes (STa, STb, LT). A subset of 62 representative isolates were serotyped by slide agglutination. For comparative purposes, multiplex PCR was also performed on the DNA of 31 ETEC isolates from 9 serotypes originating from piggeries in southern New South Wales. Results: A total of 113 (89.7%) of the isolates from Queensland possessed ETEC virulence genes, including 14 of 15 isolates from neonatal pigs (93.3%), 18 of 23 isolates from 1 to 3 week old pigs (78.3%) and 81 of 88 isolates from weaned pigs (92.1%). F4:STa:STb:LT (serotype O149) was the most prevalent pathotype in neonatal and 1-3 week old pigs and F4:STa:STb:LT (serotype O149) and F18:STa:STb:LT (serotype O141) were most prevalent in weaned pigs. In comparison, isolates obtained from neonatal pigs from New South Wales belonged to a more diverse range of pathotypes and serotypes. Conclusion: Multiplex PCR was a rapid and specific method for detecting the presence of ETEC virulence genes in porcine E coli isolates. For isolates obtained from cases of suspected colibacillosis in Queensland, growth of a heavy pure culture of haemolytic E coli was a sensitive prognostic indicator of the presence of ETEC virulence genes in the isolate. ETEC pathotypes and serotypes remained stable in Queensland piggeries over the five-year study period and appear to have changed little over the last three decades.
UR - http://www.scopus.com/inward/record.url?scp=23344435201&partnerID=8YFLogxK
U2 - 10.1111/j.1751-0813.2005.tb12745.x
DO - 10.1111/j.1751-0813.2005.tb12745.x
M3 - Review article
C2 - 15957392
AN - SCOPUS:23344435201
SN - 0005-0423
VL - 83
SP - 293
EP - 299
JO - Australian Veterinary Journal
JF - Australian Veterinary Journal
IS - 5
ER -