The use of polymerase chain reaction for determination of virulence factors of Escherichia coli strains isolated from pigs in Poland

E. coli strains isolated from pigs with postweaning diarrhea or edema disea se were tested by phenotypic and genotypic methods for the presence of viru lence antigens and genes, respectively. The slide agglutination and ELISA a nalyses were used for determination of F4, F5, F6, F17, and F41 fimbriae wh ereas the prevalence of fimbrial fedA and toxin eltI, estI, estII, stx1, st x2 and stx2e genes were recorded by the means of PCR. Only F4 antigen (ac v ariant) was found in strains of the serogroup O149:K91 isolated from pigs w ith diarrhea. PCR analyses showed that the fedA gene encoding F18 fimbriae was present in 61,9% of strains isolated from pigs with diarrhea and in 84. 2% of strains isolated from pigs with edema disease, The eltI genes encodin g heat-labile toxin I (LTI) were present only in 9 out of 21 strains recove red from pigs with diarrhea. Shiga toxin 2 variant (stx2e) genes were found in six isolates from edema disease and also in one strain from diarrhea. T he PCR test used in the study was a sensitive and valuable method for deter mination of virulence factors of E. coli strains. (C) 1999 Elsevier Science Ltd. All rights reserved.