PHENOTYPING OF E. COLISEROTYPES ASSOCIATED TO OEDEMA DISEASE

摘要

Oedema disease is a syndrome mainly affecting weaned piglets. Clinical signs of the disease often include sudden deaths, sometimes preceded by incoordination and/or swollen eyelids (1). At necropsy, stomach wall oedema is a common find. Clinical disease requires the expression of pili (F18, previously named F107) and toxin production, Verotoxin-2e (VT2e, also called Shigalike toxin He; SLT IIe), by the causative E. coli strain. Some O-groups of E. coli associated with diarrhoea in young pigs have also been shown to induce oedema disease. Several pathogenic strains of E. coli have been discussed as inducers of oedema disease but only three 0-groups (O138, O139 and O141) have repeatedly been associated with the disease (1). Also in Sweden, only strains O138, 0139 or O141 have ever been associated to oedema disease. The present study aimed to monitor the phenotypic variation within these three serotypes.