Toxins and fimbriae produced by strains of Escherichia coli isolated from feces of diarrheic calves in Algeria

Abstract

One hundred and sixty-five Escherichia coli strains isolated from several geographic areas (200 km around Algiers) from 45 diarrheic and 4 healthy calves were studied for cytotoxins (CNF1, CNF2, VT1, VT2) and fimbrial antigens (K99, F17a, F17b, F17c, Att111 and CS31A). Most of the calves were 2 to 4 weeks old. E. coli strains producing CNF2 and F17b or F17c fimbrial antigens were highly prevalent in the Ain Defla and Bordj Bou Arreridj areas with 100 and 75% of positive calves, respectively. In suburban Algiers, non-cytotoxic E. coli strains producing CS31A and/or F17c surface antigen(s) were isolated. In the Medea area both strain types were isolated. Only few VT-producing E. coli strains were identified. A specific study focusing on F17-related fimbriae produced by cytotoxin-producing E. coli strains showed that 50% of CNF2 producing isolates were F17b or F17c positive.