Detecting enteropathogenic strains of Escherichia coli of porcine origin. 2. Relationship between O and K antigens and the production of enterotoxin in strains isolated from the piglet after weaning

Abstract

The production of enterotoxin by biological tests (Yl adrenal cells and the suckling mouse) has been examined in 96 strains of Escherichia coli, isolated from sick piglets after weaning. There is a good correlation between the presence of the capsular antigen K88 and that of the thermolabile fraction (LT) of the enterotoxin (69.2 per cent of the enteropathogenic strains studied). However, the presence of the thermostable fraction (ST) of the enterotoxin of strains which, according to their serological grouping, possess in theory the two fractions LT + ST or only the ST fraction is only confirmed in a small number of strains (16 per cent) by the biological test.