Abstract
Escherichia coli isolated from suckling piglets on three farms was examined regarding the production of enterotoxins, expression of fimbriae, sensitivity and resistance patterns to tetracycline (TC), kanamycin (KM), streptomycin (SM), ampicilin (ABPC), chloramphenicol (CP) and sulfamethoxazole (SMX) and the prevalence of R plasmid. Sixty-five of 114 strains produced enterotoxins, and 53 of these strains expressed K88, K99 or 987P fimbriae. All the strains of enterotoxigenic E. coli (ETEC) indicated a resistance to each of the six drugs tested, but seven strains (14.3%) of E. coli, not producing enterotoxins, were sensitive to all the drugs tested. R plasmid was found in 59 (55.1%) of 107 drug resistant E. coli. E. coli C-600 strain transferred drug resistsnce from five strains of ETEC produced a heat-stable enterotoxin (ST). Single plasmids of about 70 or above 96 megadalton in size were found in E. coli transferred ST and drug resistance to KM or ABPC.
