title: Tylosin-resistant bacteria cultivated from agricultural soil.
abstract: In this study we analyzed the numbers and types of cultivable tylosin-resistant bacteria from six agricultural soils that differed with respect to their association with subtherapeutic antibiotic use. The proportion of tylosin-resistant bacteria to the total number of bacteria cultivated was significantly higher (7.2-16.5%) at three sites affected by subtherapeutic antibiotic use compared to three sites unaffected by subtherapeutic antibiotic use (0.7-2.5%). We also detected differences in the types of cultivable tylosin-resistant bacteria. At a site affected by subtherapeutic antibiotic use, we detected tylosin-resistant bacteria from the alpha- and beta-subdivisions of Proteobacteria. In contrast, at a site unaffected by subtherapeutic use, we detected only Streptomyces-like (high-G+C Gram-positive) tylosin-resistant bacteria. Our results suggest a link between subtherapeutic use of antibiotics and the numbers and types of antibiotic-resistant bacteria in nearby soil. However, other factors, such as soil type and temporal variation, may have also contributed to the differences observed.
authors.affiliation: Department of Civil Engineering, University of Minnesota, 500 Pillsbury Drive SE, Minneapolis, MN 55455, USA.
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Onan
authors.forename: Timothy M
authors.initials: TM
authors.lastname: LaPara
mesh_terms: D000383:Agriculture; D020561:Alphaproteobacteria / Q000187:drug effects / Q000302:isolation & purification; D000821:Animal Feed; D000822:Animal Husbandry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000517:prevention & control / Q000662:veterinary; D001482:Base Composition; D020562:Betaproteobacteria / Q000187:drug effects / Q000302:isolation & purification; D002417:Cattle; D002418:Cattle Diseases / Q000517:prevention & control; D002645:Chickens; D024881:Drug Resistance, Bacterial; D005243:Feces / Q000382:microbiology; D020563:Gammaproteobacteria / Q000187:drug effects / Q000302:isolation & purification; D008910:Minnesota; D010802:Phylogeny; D012988:Soil Microbiology; D013302:Streptomyces / Q000187:drug effects / Q000302:isolation & purification; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control; D015645:Tylosin / Q000494:pharmacology*; D003313:Zea mays
chemical_list: D000900:Anti-Bacterial Agents; D015645:Tylosin