VIRULENCE RELATED CHARACTERISTICS OF ESCHERICHIA-COLI FROM SOWS WITH MASTITIS-METRITIS-AGALACTIA (MMA) SYNDROME

Virulence related biological characteristics of thirty Escherichia col i strains isolated from sows with Mastitis-Metritis-Agalactia (MMA) sy ndrome were examined. Eighteen (60%) E. coli strains agglutinated with guinea pig RBC in the absence of D-mannose. Eleven strains possessed type 1 fimbria, as shown by seroagglutination tests. None of the E. co li strains expressed P1 and F165 fimbrial antigens. None of them produ ced enterotoxins (STa, STb and LT1), cytotoxins (VTs and CNFs) or were hemolytic (alpha and enterohemolysin). Seventeen E. coli strains prod uced aerobactin and fourteen produced colicin V. Twenty-five isolates were serum resistant. None of the isolates adhered to pig kidney cells (SK6, PK15 and C17) or to HeLa cells. These results suggest that the pathogenicity of these E. coli strains is multifactorial and further m olecular studies are required to determine markers of virulence in MMA -E. coli.