[Drug resistance and the occurrence of conjugative R plasmids in E. coli strains isolated from healthy pigs].
The methods of diffusion and serum dilutions in solid nutrient media were employed to study the drug resistance of a total of 71 Escherichia coli strains isolated from anal samples of clinically normal pigs. It was found that an essential number of the strains were resistant to penicillin, erythromycin, tetracycline, kanamycin, neomycin, chloramphenicol, oleandomycin, tylan, oxacilin, and sulfathiazol. The testing of the these strains through conjugation with E. coli C-600 as a recipient showed that 38.23 per cent of them were carriers of conjugative R-plasmids. It was concluded that the occurrence of conjugative R-plasmids in Escherichia coli isolated from normal pigs was considerable and could constitute an unsurmountable problem in the chemotherapy of such animals affected with colibacteriosis. On the other hand, the presence of R-plasmids in the microflora of clinically normal pigs could be referred to as a permanent source of drug resistance.
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003227:Conjugation, Genetic / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D005819:Genetic Markers / Q000187:drug effects; D011815:R Factors / Q000187:drug effects; D013552:Swine / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D005819:Genetic Markers
Prouchvane vŭrkhu lekarstvenata ustoĭchivost i razprostranenieto na koniugativni R-plazmidi pri shtamove E. coli, izolirani ot zdravi praseta.