LETHALITY, HEMAGGLUTINATION AND ADHESION OF ESCHERICHIA-COLI STRAINS (SEROTYPE-01) ISOLATED IN MOROCCO FROM CHICKENS WITH COLIBACILLOSIS

Six strains of Escherichia coli, isolated from chickens with colibacil losis and belonging to serotype 01, were studied. All of them were let hal for 1-day-old chicks and were strongly adherent in vitro. Hemagglu tination tests showed a strong reaction to horst and chicken erythrocy tes. This reaction was inhibited by the addition of 5% D-mannose and a lso by overnight incubation at 18 C. When the strains were heated at 6 5 C or at 85 C for 1 hr, agglutination of horse and chicken erythrocyt es was conserved only at 65 C. Purification of the subunit of fimbriae by several cycles of solubilization-crystallization using MgCl2 gave good results. The sodium dodecyl sulfate-polyacrylamide gel electropho resis showed char the molecular weight for one strain was about 18.4 k D.