Serological comparison of the Escherichia coli prototype strains for the F(Y) and Att 25 adhesions implicated in neonatal diarrhoea in calves.

Slide agglutination tests using single absorbed and double absorbed antisera indicated that the Att 25 prototype Escherichia coli strain 25 KH9 produces the F(Y) adhesion; that this E coli also produces at least one other surface antigen not found on the F(Y) prototype E coli strain 11a; and that F(Y)+ E coli strain 28a produces at least one other surface antigen not produced by the prototype strains for the F(Y) and Att 25 antigens. These antigens were found on E coli isolated from outbreaks of calf diarrhoea in the United Kingdom.