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| Bartlelt-Hunt, S.L.; De Vivo, S; Johnson, L.C.; Snow, D.D.; Kranz, W.L.; Mader, T.L.; Shapiro, C.A.; Van Donk, S.J.; Shelton, D.P.; Zhang, T.C.; Tarkalson, D.D.. |
| In this study, the fate of steroid hormones in beef cattle manure composting is evaluated. The fate of 16 steroids and metabolites was evaluated in composted manure from beef cattle administered growth promotants and from beef cattle with no steroid hormone implants. The fate of estrogens (primary detected as estrone), androgens, progesterone, and the fusarium metabolite and implant a-zearalanol were monitored in manure compost piles. First-order decay rates were calculated for steroid half-lives in compost and ranged from 8 days for androsterone to 69 days for 4-androsterone. Other steroid concentration data did not fit first-order decay models which may indicate that other microbial processes may result in steroid production or synthesis in... |
| Tipo: Article |
Palavras-chave: Feed preference; Animal; Manure. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1563/1/1519.pdf |
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| Van Donk, S.J.; Bigas, S; Kranz, W.L.; Snow, D.D.; Bartlelt-Hunt, S.L.; Mader, T.L.; Shapiro, C.A.; Shelton, D.P.; Tarkalson, D.D.; Zhang, T.C.; Ensley, S.M.. |
| A variety of naturally occurring steroid hormones are regularly excreted by livestock, while additional steroid hormones have been used as growth promoters by the livestock industry. Depending on manure age and storage conditions, both groups of compounds are likely to be present during application to crops. Recent research suggests that some estrogens, androgens and progestagens in surface waters may originate from runoff after land application of livestock manure. Groundwater may also be impacted by livestock manure when used as a nutrient source to crops and may be indicated by excess nitrate in water. Few studies have been conducted to investigate the potential of steroid hormones contamination of groundwater. The objective of this study was to monitor... |
| Tipo: Article |
Palavras-chave: Feed preference; Chemistry; Fertility. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1591/1/1548.pdf |
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| Biswas, S; Kranz, W.L.; Shapiro, C.A.; Mamo, M.; Bartlelt-Hunt, S.L.; Snow, D.D.; Tarkalson, D.D.; Shelton, D.P.; Mader, T.L.; van Donk, Simon J.; Zhang, T.C.. |
| Beef feedlot manure distributed to row crop production areas is a potential surface water contaminant source of the steroid hormones commonly used in beef cattle production. This article reports on research conducted at the University of Nebraska Haskell Agricultural Laboratory near Concord, Nebraska, in July 2009. Manure, collected from beef feedlot pens, was stockpiled for ten months prior to application to a row crop field. Previous research identified that the detection frequency of steroid hormones in beef manure varies greatly. Thus, a surrogate (17 alpha-ethynylestradiol, EE2) was applied at a rate of 75 g per ha to ensure detectable concentrations in surface runoff samples. EE2 was applied directly to beef cattle manure and to bare soil. The EE2... |
| Tipo: Article |
Palavras-chave: Manure Management; Tillage; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1554/1/1510.pdf |
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