title: Distribution of sulfamethazine, chlortetracycline and tylosin in manure and soil of Canadian feedlots after subtherapeutic use in cattle.
abstract: Feedlots are potential point sources for the flow of antibiotics into the environment due to common use of antibiotics such as sulfamethazine, chlortetracycline and tylosin. Hence soils and manures originating from a grassland control, an experimental and a commercial feedlot were analyzed and mass balances were calculated for these antibiotics. Up to 9990 microg kg(-1) sulfamethazine and 401microg kg(-1) chlortetracycline on a dry matter basis were determined in feedlot manure. Soil concentrations were two orders of magnitude smaller. This corresponds to 7-40% of the calculated residual amount. In the commercial feedlot chlortetracycline was found down to soil depths of -40 cm; sulfamethazine was still detectable 1 year after medication. Sulfamethazine and chlortetracycline were additionally determined in manure of a control treatment in the experimental feedlot where cattle never received antibiotics. This was attributed to runoff from upslope pens. Consequently, antibiotics partially persist within feedlots and may be dislocated into the surrounding environment by vertical transport and runoff.
authors.affiliation: University of Trier, FB VI: Geography/Geosciences, Soil Science Section, Campus II, 54286 Trier, Germany. aust@uni-trier.de
authors.forename: Marc-Oliver
authors.initials: MO
authors.lastname: Aust
authors.forename: Frauke
authors.initials: F
authors.lastname: Godlinski
authors.forename: Greg R
authors.initials: GR
authors.lastname: Travis
authors.forename: Xiying
authors.initials: X
authors.lastname: Hao
authors.forename: Tim A
authors.initials: TA
authors.lastname: McAllister
authors.forename: Peter
authors.initials: P
authors.lastname: Leinweber
authors.forename: Sören
authors.initials: S
authors.lastname: Thiele-Bruhn
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002170:Canada; D002417:Cattle; D002751:Chlortetracycline / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D008372:Manure / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D013418:Sulfamethazine / Q000032:analysis; D015645:Tylosin / Q000032:analysis; D019155:Veterinary Drugs / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D008372:Manure; D012987:Soil; D012989:Soil Pollutants; D019155:Veterinary Drugs; D013418:Sulfamethazine; D002751:Chlortetracycline; D015645:Tylosin