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BARTELT-HUNT L, SHANNON; SNOW D, DANIEL; KRANZ L, WILLIAM; MADER L, TERRY; Shapiro, C.A.; VAN DONK J, SIMON; SHELTON P, DAVID; Tarkalson, D.D.. |
Supplements and growth promotants containing steroid hormones are routinely administered to beef cattle to improve feeding efficiency, reduce behavioral problems, and enhance production. As a result, beef cattle manure will contain both synthetic steroids as well as a range of endogenous steroids including androgens, estrogens, and progestogens. A two-year controlled study was conducted in which beef cattle were administered steroid hormones via subcutaneous implants and feed additives and the occurrence of sixteen endogenous and synthetic steroid hormones and metabolites was evaluated in runoff from beef cattle feedlots and in manure and soil collected from feedlot surfaces. Samples were extracted and analyzed using liquid chromatography tandem mass... |
Tipo: Article |
Palavras-chave: Animal; Runoff; Manure. |
Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1450/1/1415.pdf |
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