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| Tarkalson, D.D.; Payero, J.O.; Ensley, S.M.; Shapiro, C.A.. |
| Nitrate leaching from agricultural soils can increase groundwater nitrate concentrations. The objectives of the study were to assess the accumulation and movement of nitrate in the soil profile over a 2-year period under deficit irrigation conditions following a one time application of N in cattle feedlot manure and commercial fertilizer to corn at rates to achieve yield goals expected under conditions of full irrigation. Cattle manure and ammonium nitrate were applied in 2002 at the University of Nebraska recommended rate (1M and 1F ; respectively) and cattle manure was applied at twice the recommended rate (2M) for N for the 2002 corn (Zea mays L.) crop. The recommended rate was based on expected yields under full irrigation. The manure N... |
| Tipo: Article |
Palavras-chave: Chemistry; Fertilizer; Nitrogen; Mass Import - autoclassified (may be erroneous). |
| Ano: 2006 |
URL: http://eprints.nwisrl.ars.usda.gov/59/1/1220.pdf |
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| Biswas, S; Shapiro, C.A.; Kranz, W.L.; Mader, T.L.; Shelton, D.P.; Snow, D.D.; Bartlett-Hunt, S.L.; Tarkalson, D.D.; vanDonk, S.J.; Zhang, T.C.; Ensley, S.M.. |
| Growth promoting steroids and steroid-like compounds (GPSC) used by the US beef cattle industry are potential contaminants to water resources. Manure generated in concentrated animal feeding operations contains GPSCs that may enter the environment. Several studies have focused on off-site impacts of GPSC in aquatic life and suggest possible adverse impacts such as abnormal blood hormone levels, masculinization of females, feminization of males, altered sex ratios, intersexuality and reduced fertility. Other studies point to potential human health impacts including increased incidence of human cancers, sexual disorders, and decline in male: female ratio in human beings. However, the use of GPSCs in beef production provides benefits to both cattle producers... |
| Tipo: Article |
Palavras-chave: Animal health; Animal. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1500/1/1463.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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