Susceptibility of Escherichia coli and Enterococcus faecium isolated from pigs and broiler chickens to tetracycline degradation products and distribution of tetracycline resistance determinants in E. coli from food animals

• Published in: Veterinary microbiology Vol. 95; no. 1; pp. 91 - 101
• Main Authors: Sengeløv, Gitte, Halling-Sørensen, Bent, Aarestrup, Frank M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 29-08-2003; Elsevier Science
• Subjects: Animals; Bacteriology; Biological and medical sciences; broiler chickens; Cattle; Cattle Diseases - drug therapy; Cattle Diseases - microbiology; Chickens; distribution (economics); DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Enterococcus faecium; Enterococcus faecium - drug effects; Escherichia coli; Escherichia coli - drug effects; Escherichia coli Infections - drug therapy; Escherichia coli Infections - microbiology; Escherichia coli Infections - veterinary; food animals; Fundamental and applied biological sciences. Psychology; Gram-Positive Bacterial Infections - drug therapy; Gram-Positive Bacterial Infections - microbiology; Gram-Positive Bacterial Infections - veterinary; Microbial Sensitivity Tests - veterinary; Microbiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Polymerase Chain Reaction - veterinary; Poultry Diseases - drug therapy; Poultry Diseases - microbiology; Swine; Swine Diseases - drug therapy; Swine Diseases - microbiology; tet genes; tetracycline; Tetracycline degradation products; Tetracycline resistance; Tetracycline Resistance - genetics; Tetracyclines - pharmacology; tet genes; Tetracycline degradation products; Enterococcus faecium; Tetracycline resistance; Escherichia coli; Enterococcus faedium; Gene; Swine; Bacteria; Micrococcales; Aves; Ungulata; Enterobacteriaceae; Food; Farming animal; Tetracycline derivatives; Streptococcaceae; Vertebrata; Antibiotic; Mammalia; Sensitivity resistance; Isolate; Chicken; Artiodactyla; Veterinary; Antibacterial agent
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/S0378-1135(03)00123-8

One hundred
Escherichia coli isolates from diseased and healthy pigs, cattle and broiler chickens were screened for the presence of tetracycline resistance genes
tet(A), (B), (C), (D) or (E). The
tet(A) gene was the most abundant (71% of the 100 isolates) followed by
tet(B) (25%). The predominance of
tet(A) and
tet(B) applied to all three animal species, and there was no difference between the distribution of
tet(A) and
tet(B) genes among non-pathogenic and pathogenic
E. coli in any of the animal species. The susceptibility of 20 of these isolates together with 10 tetracycline sensitive
E. coli and 18 tetracycline resistant and 10 sensitive
Enterococcus faecium to tetracyclines and tetracycline degradation products was determined. The resistant isolates showed reduced resistance to anhydrotetracycline, 4-epi-anhydrotetracycline, anhydrochlortetracycline and 4-epi-anhydrochlortetracycline. In general both the tetracycline resistant and susceptible
E. faecium were more susceptible to the compounds tested than
E. coli.