Antibiotic resistance and Hly plasmids in serotypes of Escherichia coli associated with porcine enteric disease.
A total of 359 hemolytic Escherichia coli strains, representing eight pig pathogenic serotypes and isolated from pigs with enteric disease, was tested for transferable resistance to eight antibiotics. The co-transfer of plasmids controlling hemolysin production (Hly) with antibiotic resistance plasmids (R-factors) was evaluated. Transferable resistance to tetracycline, streptomycin, and/or sulfonamides was found in 47% of the total number of strains and 80% of the resistant ones. Chloramphenicol resistance was seldom seen. Co-transfer of Hly with R-factors occurred in 22.5% of the strains, generally to a degree excluding a genetic linkage. Stable coexistence of two R-factors in a cell was indicated by transfer patterns in 29 of the strains.
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003227:Conjugation, Genetic; D003470:Culture Media; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000276:immunology*; D005111:Extrachromosomal Inheritance; D010957:Plasmids; D011815:R Factors; D012703:Serotyping; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D003470:Culture Media