Two finishing experiments were conducted to determine the effects of concentration (Exp. 1) and composition of wet corn gluten feed (Exp. 2) in steam-flaked corn-based diets on feedlot steer performance. In Exp. 1, 192 English x Continental crossbred steer calves (299 +/- 0.6 kg) were used in a completely randomized design with six dietary treatments (four pens per treatment). Treatments were s...

Three experiments were conducted to evaluate the impact of the Bacillus thuringiensis (Bt)-11 transformation event in two parental corn hybrids differing in date of maturity on beef and dairy cattle performance. Sixteen lactating Holstein dairy cows in replicated 4 x 4 Latin squares were assigned to four diets in a 2 x 2 factorial arrangement: Bt vs non-Bt trait and early- vs late-maturing corn...

This study was designed to evaluate the improved version of the Root Zone Water Quality Model (RZWQM) using 6 yr (1992-1997) of field-measured data from a field within Walnut Creek watershed located in central Iowa. Measured data included subsurface drainage flows, NO3-N concentrations and loads in subsurface drainage water, and corn (Zea mays L.) and soybean [Glycine mar (L.) Merr.] yields. Th...

Ecological nutrient management is a strategy that can help create resilient cropping systems and reduce the negative impact agricultural have on environment. enhances plant-soil-microbial interactions optimizes crop production while providing key ecosystem services. Incorporating perennial legumes into rotations implementing no-till to enhance organic nitrogen (N) soil pools could need for inor...

Seed-based pest management tools, such as transgenes and seed treatments, are emerging as viable alternatives to conventional insecticide applications in numerous crops, and often occur as coupled technologies. Seed-based technologies have been readily adopted in maize, for which ecological studies are needed to examine effects to farmland biodiversity. We compared the response of nontarget col...

Increases in agricultural commodity price triggered by ethanol production and other socioeconomic conditions have dramatically affected land uses and agronomic practices in the U.S. This study used crop-specific land cover data from the U.S. Department of Agriculture (USDA) to analyze agricultural expansion and crop rotation pattern from 2006 to 2013 in the Midwest Corn Belt (MWCB): nine states...

Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a serious pest of corn in the United States, and recent management of western corn rootworm has included planting of Bt corn. Beginning in 2009, western corn rootworm populations with resistance to Cry3Bb1 corn and mCry3A corn were found in Iowa and elsewhere. To date, western corn rootworm populations...

Two experiments were conducted to evaluate the effects of a winter feeding strategy on the performance, lactation, reproduction, and feed costs of springcalving, lactating beef cows. In Exp. 1, Angus (n = 66) and Simmental (n = 70) cows were allotted to 1 of 4 treatments: 1) distillers dried grains with solubles (DDGS) and free-choice corn residue bales; 2) corn bran and DDGS and freechoice cor...

This study evaluated fermentation characteristics and fungal numbers of napiergrass silages prepared with and without added raw or heated corn meal (10%, fresh-weight basis) at ensiling. Corn was added to napiergrass so that the silage would contain concentrate similar to that of corn silage with minimum grain content. The silages treated with raw or heated corn were fed to dairy does to compar...