Organic Beef Cattle Grazing Demonstration

There is growing interest in grass-fed organic beef. The objective of this study was to compare the performance of conventional feedlot-based cattle finishing with organic beef cattle finishing

Cows in the Corn Grazing Project

Corn is the most productive grass grown in Iowa with dry matter yields often exceeding 6 t/a. Harvesting corn by grazing can provide abundant pasture in mid- to late-summer when pastures in southern Iowa normally make little growth. This approach eliminates harvesting, drying, storage, and transportation costs associated with marketing the grain and leaves almost all of the surplus or waste nutrients in the field. Objectives of this project were to measure animal performance when standing corn crop was the sole feed source for pregnant diary heifers and to increase our understanding of the management practices necessary to optimize the use of this feed source

Spontaneous Iliac Arteriovenous Fistula, High-Output Heart Failure, and Cardiac Arrest

High-output heart failure is a potentially life-threatening condition that can lead to cardiac arrest. The most common causes of this condition are obesity, liver disease, arteriovenous shunts, lung disease, and myeloproliferative disorders, however the exact prevalence remains uncertain [1]. Here we describe an unusual case of cardiac arrest as a consequence of high-output heart failure, secondary to rupture of an iliac artery aneurysm into the common iliac vein, with arteriovenous (AV) fistula formation

English Learners in California Schools: Unequal resources, 'Unequal outcomes

The Williams vs the State of California class action suit on behalf of poor children in that state argues that California provides a fundamentally inequitable education to students based on wealth and language status. This article, an earlier version of which was prepared as background to that case, reviews the conditions of schooling for English learners in the state with the largest population of such students, totaling nearly 1.6 million in 2003, and comprising about 40 percent of nation’s English learners. We argue, with evidence, that there are seven aspects of the schooling of English language learners where students receive an education that is demonstrably inferior to that of English speakers. For example, these students are assigned to less qualified teachers, are provided with inferior curriculum and less time to cover it, are housed in inferior facilities where they are often segregated from English speaking peers, and are assessed by invalid instruments that provide little, if any, information about their actual achievement. We end with suggestions for ways in which teachers, administrators, and policymakers can begin to address these inequities, even while legal remedies may remain in the distant future

Evaluation of Year-round Forage Management Systems for Spring- and Fall-Calving Beef Cows

Stored feeds make up almost half the cost of production for cow–calf enterprises in Iowa. Therefore, any reduction in the amount of stored feeds needed to maintain cows through the winter can have an impact on overall costs of maintaining the herd. Two resources that may be used to reduce the use of stored feeds are corn-crop residues and stockpiled perennial forages, which may be grazed during the winter. The objective of this experiment was to design and evaluate grazing systems to utilize such resources

Evaluation of a Year-Round Grazing System: Winter Progress Report

The winter component of a year-round grazing system involving grazing of corn crop residues followed by grazing stockpiled grass legume forages was compared at the McNay Research Farm with that of the winter component of a minimal land system that maintained cows in drylot,. In the summer of 1995, two cuttings of hay were harvested from two 15-acre fields containing “Johnston” endophyte-free tall fescue and red clover, and two cuttings of hay were taken from two 15-acre fields of smooth bromegrass and red clover. Hay yields were 4,236 and 4,600 pounds of dry matter per acre for the tall fescue--red clover and smooth bromegrass--red clover. Following grain harvest four 7.5-acre fields containing corn crop residue were stocked with cows at midgestation at an allowance of 1.5 acres per cow. Forage yields at the initiation of corn crop grazing were 3,766pounds of dry matter per acre for corn crop residue, 1,748 pounds for tall fescue--red clover, and 1,.880 pounds for smooth bromegrass--red clover. Corn crop residues and stockpiled forages were grazed in a strip stocking system. For comparison, 20 cows were placed in two drylots simultaneously to the initiation of corn crop grazing where they remained throughout the winter and spring grazing seasons. Cows maintained in drylot or grazing corn crop residue and stockpiled forages were supplemented with hay as large round bales to maintain a body condition score of five. No seasonal differences in body weight and body condition were observed between grazing cows or cows maintained in drylot, but grazing cows required 87% and 84% less harvested hay than cows in drylot during the winter and spring respectively. Because less hay was needed to maintain grazing cows, an excess of 11,905 and 12,803 pounds of hay dry matter per cow remained in the year-round grazing system. During corn crop grazing, organic matter yield decreased at 27.3 pounds of organic matter per day from grazed areas of corn crop residue. Organic matter losses due to weathering were 9.4, 12.9, and 15.8 pounds per day in corn crop residue, tall fescue-red clover and smooth bromegrass-red clover. Organic matter losses from grazed and ungrazed areas during stockpiled grazing were 7.3 and 6.9 for tall fescue--red clover and 2.1, 2.9 for smooth bromegrass--red clover

Efficacy of Grazing Stockpiled Perennial Forages for Winter Maintenance of Beef Cows

In a three year study, wintering systems utilizing the grazing of stockpiled perennial hay crop forages or corn crop residues were compared to maintaining cows in a drylot. In the summer of 1992, two cuttings of hay were harvested (June 22 and August 2) from three 10-acre fields containing “Johnstone” endophyte-free tall fescue and “Spreador II” alfalfa, and one cutting of hay was harvested from three 10- acre fields of smooth brome grass. “Arlington” red clover was frost-seeded into the smooth bromegrass fields in 1993 and into tall fescue-alfalfa and smooth bromegrass fields into 1994. Two cuttings of hay were harvested from all fields in subsequent years, and three-year average hay yields for tall fescue-alfalfa and smooth bromegrass-red clover were 4,336 and 3,481 pounds per acre, respectively. Regrowth of the forage following the August hay harvest of each year was accumulated for winter grazing. Following a killing frost in each year, two fields of each stockpiled forage were stocked with cows in midgestation at two acres per cow. Two 10-acre fields of corn crop residues were also stocked at two acres per cow, following the grain harvest. Mean dry matter forage yields at the initiation of grazing were 1,853, 2,173 and 5,797 pounds per acre for fields containing tall fescue-alfalfa, smooth bromegrass-red clover, and cornstalks, respectively. A drylot was stocked with 18 cows in 1992 and 1993 and 10 cows in 1994. All cows were fed hay as necessary to maintain a body condition score of five. During grazing, mean losses of organic matter were -6.4, -7.6, and -10.7 pounds per acre per cow from tall fescue-alfalfa, smooth bromegrass-red clover, and cornstalk fields. Average organic matter loss rates from stockpiled forages due to weathering alone were equal to only 30% of the weathering losses of the corn crop residues. In vitro digestibility of both stockpiled forages and cornstalks decreased at equal rates during grazing each year, with respective annual loss rates of .14, .08, and .06% per day. Cows grazing corn crop residues required an average of 1,321 pounds per cow less hay than cows maintained in the drylot to maintain equivalent body condition during the grazing season. Cows grazing tall fescue-alfalfa or smooth bromegrass-red clover had body weight gains and condition score changes equal to cows maintained in a drylot but required 64% and 62% less harvested hay than cows in the drylot during the grazing season. Over the entire stored forage cows grazing tall fescue-alfalfa and smooth bromegrass-red clover required an average of 2,390 and 2,337 pounds per cow less than those maintained in the drylot. Because less hay was needed to maintain cows grazing stockpiled forages, average annual excesses of 5,629 and 3,868 pounds of hay dry matter per cow remained in the stockpiled tall fescue-alfalfa and smooth bromegrass-red clover systems

Evaluation of a Year-Round Grazing System: Summer Cow-Calf Progress Report

A comparison was made between two different summer grazing systems. One system was the summer component of a year-round grazing system, involving the rotational stocking of smooth bromegrass--orchardgrass--birdsfoot trefoil pastures and winter stockpiles pastures with cowcalf pairs co-grazing with stocker yearlings at .75 animal units per acre. That system was compared with a minimal land system involving the rotational stocking of smooth bromegrass--orchardgrass-- birdsfoot trefoil summer pastures with cow-calf pairs grazing at .64 animal units per acre and hay removal from 25% of the pasture. Stocker yearlings or hay removal were used as management tools to remove excess forage and optimize forage quality. Hay was removed once from three fourths of the winter stockpiled pastures and one fourth of the allocated summer pastures. Cow-calf pairs grazing in the year-round system utilized on fourth of the winter stockpile pastures due to lack of forage, whereas cow-calf pairs grazing with hay removal were supplemented with harvested hay for two weeks during the summer. Grazing system did not affect cow body weight, condition score, or daily calf weight gain. Growing animal production per acre was affected by grazing system, with the minimal land system having a higher production level

Effects of Corn Crop Residue Grazing on Soil Physical Properties and Subsequent Soybean Production in a Corn–Soybean Crop Rotation

For three years beginning in 1999, a 96-acre field near Atlantic, Iowa was used to study the effects of corn residue grazing by beef cows on soil characteristics and soybean yields in subsequent years. Each winter, cows were allowed to graze corn crop residues inside selected paddocks in four sub-fields over five monthly periods. To compare the effects of grazing, one paddock was left as an ungrazed control. At the end of grazing in the spring, soil bulk density, moisture content, and penetration resistance were measured inside and 15 ft outside twelve grazing exclosures in each paddock. Soil surface roughness, texture, and type were also measured in twelve locations in each paddock. Corn crop residues were collected for yield, cover, and composition at the initiation, middle and termination of grazing. Precipitation and soil temperature also were recorded throughout the grazing season. Each following year, soybeans were planted in replicated subfields with disking or no tillage and harvested using a combine equipped with a yield monitor and global positioning system (GPS). Cattle grazing corn crop residue has shown no effect on soil bulk density, but there has been a measurable effect on penetration resistance in paddocks grazed in October and November (P\u3c 0.05). There is an increase in soil surface roughness during certain periods of cattle grazing where 75% of the variation can be contributed to increase in the amount of time soil temperature is above freezing. Cattle grazing had no effect on soybean plant population. However, 36 and 38% of the variation in soybean yield can be attributed to penetration resistance and soil surface roughness