results of a nationwide survey to determine feedstuffs fed to lactating dairy cows.a nationwide survey to determine feedstuffs used in the diets of dairy cows was conducted. this survey was mailed to dairy nutritionists at universities in each state to describe the use of 144 feedstuffs. twenty-eight states responded and were grouped by region as follows: northeast (maine, maryland, new hampshire, new york, ohio, vermont, and west virginia), northwest (idaho, oregon, and washington), midwest (iowa, illinois, michigan, minnesota, missouri, nebraska, north dakota, south dakota, ...199910068966
a survey of selected heavy metal concentrations in wisconsin dairy feeds.heavy metals such as zinc (zn), copper (cu), chromium (cr), arsenic (as), cadmium (cd), and lead (pb) are potential bioaccumulative toxins of the dairy production system. the heavy metal content of dairy feeds, however, remains poorly documented, particularly in the united states. this survey determined the heavy metal content of 203 typical dairy ration components sampled from 54 dairy farms in wisconsin. lowest heavy metal concentrations were found in homegrown alfalfa (medicago sativa l.) hay ...200516027206
genetically engineered plants, endangered species, and risk: a temporal and spatial exposure assessment for karner blue butterfly larvae and bt maize pollen.genetically engineered maize (zea mays) containing insecticidal endotoxin proteins from bacillus thuringiensis (bt) delta-endotoxin proteins has been adopted widely in the midwestern united states. the proteins are toxic to several lepidopteran species and because a variety of maize tissues, including pollen, may express the endotoxins, the probability of exposure to nontarget species, including endangered species, needs to be understood. the objective of this study was to assess the potential t ...200616834638
integrated biosphere simulator (ibis) yield and nitrate loss predictions for wisconsin maize receiving varied amounts of nitrogen fertilizer.agriculture in the u.s. midwest faces the formidable challenge of improving crop productivity while simultaneously mitigating the environmental consequences of intense management. this study examined the simultaneous response of nitrate nitrogen (no3-n) leaching losses and maize (zea mays l.) yield to varied fertilizer n management using field observations and the integrated biosphere simulator (ibis) model. the model was validated against six years of field observations in chisel-plowed maize p ...200312549565
corn residue level and manure application timing effects on phosphorus losses in runoff.growing interest in corn (zea mays l.) silage utilization on wisconsin dairy farms may have implications for nutrient losses from agricultural lands. increasing the silage cutting height will increase residue cover and could reduce off-site migration of sediments and associated constituents compared with conventional silage harvesting. we examined the effects of residue level and manure application timing on phosphorus (p) losses in runoff from no-till corn. treatments included conventional corn ...201716091615
increasing corn for biofuel production reduces biocontrol services in agricultural landscapes.increased demand for corn grain as an ethanol feedstock is altering u.s. agricultural landscapes and the ecosystem services they provide. from 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic imp ...200819075234
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