Digital Commons Network^™

Characterization Of Biological Types Of Cattle (Cycle Vii): Influence Of Postpartum Interval And Estrous Cycle Length On Fertility, R. A. Cushman, M. F. Allan, R. M. Thallman, L. V. Cundiff

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Genetic improvement in reproductive efficiency through selection is difficult because many reproductive traits are binomial and have low heritabilities. Before genetic markers can be generated for fertility in cows, greater characterization of reproductive phenotypes is needed to understand the components of the trait. The current study tested the hypotheses that: 1) breeds vary in postpartum interval to estrus (PPIE) and estrous cycle length, 2) a longer estrous cycle immediately before breeding increased pregnancy rates, and 3) a greater number of cycles before breeding increased conception rates. The postpartum interval to estrus, estrous cycle length, and number of cycles before breeding …

Effects Of Graded Levels Of Sorghum Wet Distiller’S Grains And Degraded Intake Protein Supply On Performance And Carcass Characteristics Of Feedlot Cattle Fed Steam-Flaked Corn-Based Diets, J. T. Vasconcelos, L. M. Shaw, K. A. Lemon, N. A. Cole, M. L. Galyean

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Two experiments evaluated different levels of sorghum wet distiller’s grains plus solubles (SWDG) and effects of increasing the degraded intake protein (DIP) concentration in diets containing SWDG on performance and carcass characteristics of feedlot cattle. In Exp. 1, 200 beef steers (average BW = 404 kg) were fed increasing levels of SWDG (0, 5, 10, and 15% of DM) and one level of corn wet distiller’s grains plus solubles (10% of DM), which replaced steamflaked corn in a high-concentrate diet. Final BW (P = 0.04) and overall ADG (P = 0.01) decreased linearly with increasing levels of SWDG. Increasing SWDG …

Livestock Management During Drought In The Northern Great Plains. I. A Practical Predictor Of Annual Forage Production, R. E. Kruse, M. W. Tess, R. K. Heitschmidt

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This research addressed the hypothesis that spring precipitation data can be used to detect agricultural drought early in the growing season. The Rangetek range model was used to simulate yearly forage data based on historical precipitation and temperature records from the USDA-ARS Fort Keogh Livestock and Range Research Laboratory (Miles City, MT) and the Agriculture and Agri-Food Canada Manyberries Substation (Lethbridge, AB, Canada). Monthly total precipitation and monthly average maximum and minimum temperatures were used to develop regression equations predicting growing season forage production at the Fort Keogh Laboratory and Manyberries Substation. At Fort Keogh Laboratory, a combination of fall …

Identification Of Compounds From Etonia Rosemary (Conradina Etonia), Brian P. Quinn, Ulrich R. Bernier, Matthew M. Booth

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Mosquitoes transmit pathogens that result in diseases harmful to human, livestock, and wildlife hosts. Numerous measures can be used to reduce insect-borne disease risk to humans, and one approach is the use of topical repellents to prevent host-seeking arthropods from taking a blood meal. A current emphasis in the development of new repellents is that they be safe. Therefore, natural products sources are increasingly being explored. Compounds from plants of the mint family (Lamiaceae) have been demonstrated to be insect repellents. This study examines compounds from Etonia rosemary (Conradina etonia) to identify compounds for examination as insect repellents. …

Using Comparative Genomics To Reorder The Human Genome Sequence Into A Virtual Sheep Genome, Brian Dalrymple, Ewen Kirkness, Mikhail Nefedov, Sean Mcwilliam, Abhirami Ratnakumar, Wes Barris, Shaying Zhao, Jyoti Shetty, Jillian Maddox, Margaret O'Grady, Frank Nicholas, Allan Crawford, Tim Smith, Pieter De Jong, John Mcewan, V. Hutton Oddy, Noelle Cockett

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Is it possible to construct an accurate and detailed subgene-level map of a genome using bacterial artificial chromosome (BAC) end sequences, a sparse marker map, and the sequences of other genomes?
Results: A sheep BAC library, CHORI-243, was constructed and the BAC end sequences were determined and mapped with high sensitivity and low specificity onto the frameworks of the human, dog, and cow genomes. To maximize genome coverage, the coordinates of all BAC end sequence hits to the cow and dog genomes were also converted to the equivalent human genome coordinates. The 84,624 sheep BACs (about 5.4-fold genome coverage) …

Growth And Carcass Characteristics In Goat Kids Fed Grass- And Alfalfa-Hay-Based Diets With Limited Concentrate Supplementation, S. Wildeus, J.-M. Luginbuhl, K. E. Turner, Y. L. Nutall, J. R. Collins

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Two experiments were conducted to evaluate the effect of feeding legume hay (alfalfa; Medicago sativa L.) or mixed-grass hay on ADG and carcass characteristics of growing goats.

Dominant Species Constrain Effects Of Species Diversity On Temporal Variability In Biomass Production Of Tallgrass Prairie, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Species diversity is thought to stabilize functioning of plant communities. An alternative view is that stability depends more on dynamics of dominant species than on diversity. We compared inter-annual variability (inverse of stability) of aboveground biomass in paired restored and remnant tallgrass prairies at two locations in central Texas, USA. Data from these two locations were used to test the hypothesis that greater richness and evenness in remnant than restored prairies would reduce variability in aboveground biomass in response to natural variation in rainfall. Restored prairies were chosen to be similar to paired remnant prairies in characteristics other than species …

Response Of Three Ecotypes Of Maca (Lepidium Meyenii Walp.) To Five Levels Of Ovine Manure In The Community Of Yampupata (Manco Kapac Province - La Paz), Sabina Quispe Paye

Theses and Dissertations

This study was conducted in the community of Yampupata, in the municipality of Copacabana, in the Manco Kapac province, La Paz, to an altitude of 3841 m.a.s.l, agricultural campaign 2003-2004. The purpose of the study was to determine and compare the fenological stages (germination, growth, leafing, and harvesting), hypocotyl yield (dry and fresh), classification of the hypocotyl (diameter, length, etc.), and the economical evaluation as well. The experiment set up was installed in the lower region of the community, dedicated to agriculture, performing all the aforementioned activities together for the period of a year. The experimental design was of Random …

Grassland Composition Affects Season Shifts In Seed Preference By Pogonomyrmex Barbatus (Hymenoptera: Myrmicinae) In The Edwards Plateau, Texas, Nancy Nicolai, Jerry L. Cook, Fred E. Smeins

Department of Agronomy and Horticulture: Faculty Publications

The effects of season and community composition as generated by livestock herbivory of differing intensity on seed species preference by Pogonomyrmex barbatus (F. Smith) were studied in a semiarid savanna on the Edward’s Plateau, TX. Seasonal differences in nutrient requirements of the colony could lead to differential preferences for seeds harvested in spring and fall. Field cafeteria studies were conducted to test the hypothesis that late successional species, with their high nutrient content, would be chosen regardless of grazing intensity or season. Commercial seeds of known nutrient content were used to test the hypothesis that high protein levels would be …

World Agriculture And Environment: A Commodity-By-Commodity Guide To Impacts And Practices [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

This comprehensive reference book provides a good overview of global agriculture at the end of the millennium. In the introduction, author Jason Clay brings his long experience—in farming, teaching, and government service—into the presentation of a balanced perspective on how production must be balanced with concern for the environment. Now with World Wildlife Fund, he couples a background in economics, anthropology and geography with considerable professional experience in aquaculture and cooperation in the private sector to explore multiple aspects of agriculture and food production. He is particularly effective in discussing the economic and environmental sustainability of the food system, although …

The Ripple Effect: Biofuels, Food Security, And The Environment, Rosamond L. Naylor, Adam Liska, Marshall B. Burke, Walter P. Falcon, Joanne C. Gaskell, Scott D. Rozelle, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

The integration of the agricultural and energy sectors caused by rapid growth in the biofuels market signals a new era in food policy and sustainable development. For the first time in decades, agricultural commodity markets could experience a sustained increase in prices, breaking the long-term price decline that has benefited food consumers worldwide. Whether this transition occurs—and how it will affect global hunger and poverty—remain to be seen. Will food markets begin to track the volatile energy market in terms of price and availability? Will changes in agricultural commodity markets benefit net food producers and raise farm incomes in poor …

Plant Species Richness In Relation To Pasture Position, Management, And Scale, John A. Guretzky, Kenneth J. Moore, C. Lee Burras, E. Charles Brummer

Department of Agronomy and Horticulture: Faculty Publications

The objective of this research was to describe how landscape position, grazing management, and scale affected overall plant species richness and species richness per functional group in temperate pastures located in the central United States. The effects and interactions of summit, backslope, and toeslope positions and continuous, rotational, and nongrazed stocking systems on species richness were examined at sample scales of 0.18 m² and 4.5 m². Landscape position explained 40–63% of species richness variation at 0.18 m² compared to 3–26% at 4.5 m² for overall, perennial, perennial grass, vegetative-spreading grass, perennial herb, and perennial N …

Barcsoysnp23: A Panel Of 23 Selected Snps For Soybean Cultivar Identification, M. S. Yoon, Q.J. Song, I. Y. Choi, James E. Specht, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

This report describes a set of 23 informative SNPs (BARCSoySNP23) distributed on 19 of the 20 soybean linkage groups that can be used for soybean cultivar identification. Selection of the SNPs to include in this set was made based upon the information provided by each SNP for distinguishing a diverse set of soybean genotypes as well as the linkage map position of each SNP. The genotypes included the ancestors of North American cultivars, modern North American cultivars and a group of Korean cultivars. The procedure used to identify this subset of highly informative SNP markers resulted in a significant increase …

Structural Attributes Of The Hypogeous Holoparasite Hydnora Triceps Drège & Meyer (Hydnoraceae), Kushan U. Tennakoon, Jay F. Bolin, Lytton J. Musselman, Erika Maas

Biological Sciences Faculty Publications

The morphology of the hypogeous root holoparasite Hydnora triceps is highly reduced, and as with many holoparasites, the vegetative body is difficult to interpret. The vegetative body of H. triceps has been historically considered a "pilot root" studded with lateral appendages known as "haustorial roots." We found the vegetative body of H. triceps to consist of a rhizome with a thickened root-cap-like structure that covered a vegetative shoot apical meristem. From the apical meristem, procambial strands originated and developed into endarch collateral vascular bundles arranged radially around a pith without an interfascicular cambium. Xylem vessels had scalariform pitting and simple …

Effects Of Conservation Practices On Aquatic Habitats And Fauna, Scott Knight, Kathryn Boyer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A major goal of both state and federal agricultural and environmental agencies in the United States is sustainable management of watersheds where agriculture is a dominant land use. Because watershed processes and conditions directly and indirectly affect soil, water, air, plants, animals, and humans, USDA NRCS encourages a watershed approach to management of agricultural operations in the United States. This requires a suite of approaches or practices that address natural resource concerns in uplands and stream corridors. Land clearing, leveling, draining, tilling, fertilizing, and harvesting together create prolonged perturbations manifested in the ecological and physical conditions of streams and rivers. …

Estimates Of Gross Transformation Rates Of Dairy Manure N Using 15N Pool Dilution, T. S. Griffin

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Most measurements of dairy manure nitrogen (N) availability depend on net
changes in soil inorganic N concentration over time, which overlooks the cycling of manure N in the soil. Gross transformations of manure N, including mineralization (m), immobilization (i), and nitrification (n), can be quantified using ¹⁵N pool dilution methods. This research measures gross m, n, and i resulting from application of four freeze-dried dairy manures that had distinctly different patterns of N availability. A sandy loam soil (coarse-loamy, mixed, frigid Typic Haplorthod) was amended with four different freeze-dried dairy manures and …

Compost And Manure Effects On Fertilized Corn Silage Yield And Nitrogen Uptake Under Irrigation, Gary A. Lehrsch, D. C. Kincaid

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Dairy manure increases the yields of dry bean (Phaseolus vulgaris L.) and spring wheat (Triticum aestivum L.) from eroded, furrow-irrigated soils and may increase corn (Zea mays L.) silage yield from steeper eroded areas under sprinkler irrigation. In a 2-year field study in southern Idaho on Portneuf silt loam (coarse silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid), the effects of a one-time, fall application of 29 or 72 Mg ha^-1 of dry manure or 22 or 47 Mg ha^-1 of dry compost on subsequent silage yield and nitrogen (N) uptake from previously eroded, sprinkler-irrigated hill …

Morphological And Histochemical Characterization Of The Seminiferous Epithelial And Leydig Cells Of The Turkey, M. R. Bakst, V. Akuffo, P. Trefil, J. P. Brillard

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Unlike mammals, there is little fundamental information about spermatogenesis in birds. This study was undertaken to clarify the morphology, histochemistry, and lectin affinity of the seminiferous epithelial cells and Leydig cells in pre-pubertal (8- to 15-week old) and adult (40- to 44-week old) domestic turkeys. In adult turkeys, three types of spermatogonia were defined based on their chromatin distribution and nuclear morphology: the dark type A(A_d); the pale type A(A_p); and the type B. The A_d is the least numerous and least conspicuous and consequently difficult to locate. Based on its spatial distribution and overall …

2007 Census Of Agriculture

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Introduction .......... VII

State Map .......... 1

Figures .......... 2-6

Tables

Chapter 1. State Data .......... 7-236

Chapter 2. County Data .......... 249-617

Appendices

Census of Agriculture Methodology .......... A-1

General Explanation and Census of Agriculture Report Form .......... B-1

Index .......... Index 1

Publication Program .......... Inside Back Cover

Mosquito And Fly Control Research By The Usda-Ars Center For Medical, Agriculture And Veterinary Entomology (Cmave) In The Deployed War-Fighter Protection (Dwfp) Program, Kenneth J. Linthicum, Sandra A. Allan, Donald Barnard, James Becnel, Ulrich R. Bernier, Seth Britch, Gary Clark, Miriam Cooperband, Chris Geden, Jerome Hogsette, Daniel Kline, Roberto Pereira, Julia Pridgeon, Brian Quinn, Craig Welch, Liming Zhao

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Despite existing measures to prevent and control arthropod-borne diseases in military units, these diseases continue to be serious threats to deployed troops. Due to a shrinking list of safe, cost-effective pesticides for control of disease vectors, new and improved toxicants and methods for delivery are needed by the armed forces. Since 2004, the USDA Agricultural Research Service (ARS) has participated in the Department of Defense (DOD) - sponsored Deployed War-Fighter Protection (DWFP) program to identify and develop new tools for combating pest and vector species that impact deployed war-fighters. Ongoing research at the USDA-ARS Center for Medical, Agricultural and Veterinary …

Isolation Of Salmonella Enterica And Shiga-Toxigenic Escherichia Coli O157 From Feces Of Animals In Public Contact Areas Of United States Zoological Parks, James E. Keen, Lisa M. Durso, Thomas P. Meehan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The fecal prevalence of subclinical Salmonella enterica and Shiga-toxigenic Escherichia coli O157 among animals in human-animal contact exhibits at institutions in the United States accredited by the Association of Zoos and Aquariums was estimated to assess public health risk. The prevalence was less than 0.6% for both zoonotic pathogens among 997 animals sampled at 36 exhibits.

Physiological Host Range Of Ceratapion Basicorne, A Prospective Biological Control Agent Of Centaurea Solstitialis (Asteraceae), Lincoln Smith

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Ceratapion basicorne (Coleoptera: Apionidae) is a weevil native to Europe and western Asia that is being evaluated as a prospective classical biological control agent of Centaurea solstitialis (yellow starthistle) in the United States. Host plant specificity of the insect was evaluated in no-choice oviposition experiments. Feeding on leaf tissue by adult females was highly correlated to oviposition rate, both of which occurred primarily on plants in the tribe Cardueae, and especially those in the monophyletic subtribe Centaureinae. The highest rates of larval development occurred on Ce. solstitialis and Centaurea cyanus (bachelor’s button, garden cornflower), and there was significant development on …

Comparing Citizens' And Managers' Concerns About Sagebrush Management And Restoration In The Great Basin, Mark W. Brunson, Jennifer Peterson

Reports

The Great Basin sagebrush steppe ecosystem is among the most imperiled in the U.S. Cheatgrass invasion, conifer encroachment, and catastrophic wildfires are considered to be primary catalysts of decline. Efforts are underway to restore and increase the resiliency of this damaged ecosystem through broad-scale applications of fuel reduction and restoration treatments involving mechanical removal, prescribed fire, and herbicide application. While research points to the potential benefits of these treatments, controversy and challenge often surface when treatments are proposed on public lands. Therefore it is critical for land managers to understand the views held by key stakeholder groups concerning management and …

Environmental Abundance Of Anopheles (Diptera: Culicidae) Larval Habitats On Land Cover Change Sites In Karima Village, Mwea Rice Scheme, Kenya, Benjamin G. Jacob, Ephantus Muturi, Patrick Halbig, Joseph Mwangangi, R. K. Wanjogu, Enock Mpanga, Jose Funes, Josephat Shililu, John Githure, James L. Regens, Robert J. Novak

All Peer-Reviewed Publications

A study was carried out at Karima Village in the Mwea Rice Irrigation Scheme in Kenya to assess the impact of rice husbandry and associated land cover change for mosquito larval abundance. A multi-temporal, land use land cover (LULC) classification dataset incorporating distributions of Anopheles arabiensis aquatic larval habitats was produced in ERDAS Imagine version 8.7 using combined images from IKONOS at 4m spatial resolution from 2005 and Landsat Thematic Mapper (TM)™ classification data at 30-meters spatial resolution from 1988 for Karima. Of 207 larval habitats sampled, most were either canals (53.4%) or paddies (45.9%), and only one habitat was …

Distribution And Relative Importance Of Lepidopteran Cereal Stemborers And Their Parasitoids In Uganda, T. Matama-Kauma, F. Schulthess, J. A. Ogwang, J. M. Mueke, C. O. Omwega

All Peer-Reviewed Publications

Infestation levels and parasitism of lepidopteran stemborers on maize were assessed in four agroecological zones (AEZ) in Uganda. The indigenous noctuid Busseola fusca Fuller (Noctuidae) and the invasive Chilo partellus Swinhoe (Crambidae) were the most important stemborers recorded. C. partellus represented 77% of the stemborers in the Eastern AEZ while B. fusca was dominant in the other AEZs, accounting for 60-79%. The proportion of infested plants was between 16% and 45% and borer density between 0.2 and 1.0 borers per plant. There was no clear relationship between damage and stem tunneling, which is often used to estimate yield loss. Telenomus …

Genetic Diversity And Low Reproductive Success In Isolated Populations Of Utah Juniper (Juniperus Osteosperma, Cupressaceae), Loreen Allphin, Val J. Anderson, Amy F. Hunt

Faculty Publications

Utah juniper (Juniperus osteosperma) has greatly expanded its historical range in the western United States. Management plans for the species have focused on curtailing its encroachment into sagebrush and grassland communities. These plans often include burning or other methods of elimination. These methods may result in subdivision or fragmentation of existing juniper stands. We initiated a study at Dugway Proving Ground, a U.S. Army facility, to examine the effects of fragmentation on the reproductive success of Utah juniper in isolated populations. We used enzyme electrophoresis to quantify genetic variability in isolated populations. We also determined population reproductive success by examining …

Are Botanists Becoming The Dinosaurs Of Biology In The 21st Century?, Dennis W. Woodland

Faculty Publications

The number of botany students, botany classes, botany departments in universities and botanists attending conventions has been declining over many years in North America. This is part of a general trend throughout the field of organismal biology, not just botany. The history leading up to the situation today in North America, is discussed and reasons are given for this trend over the last century of time. Seven ways to keep botany a viable occupation are discussed otherwise botany, in the 21st century, may go the way of the dinosaur. © 2007.

Mechanism Of Intraspecific Toxin Inhibition In Aspergillus Flavus, Changwei Huang

LSU Master's Theses

Atoxigenic Aspergillus flavus was demonstrated by others as a promising biocontrol agent to minimize preharvest aflatoxins in susceptible crops. But the mechanism was unclear. A filter insert-well plate system was used to study the mechanism in lab. There was no inhibition when toxigenic A. flavus isolate 53 and inhibitory atoxigenic isolates were separated by 0.4 µm membrane, approximately 50% inhibition occurred when separated by 12 µm membrane, and complete inhibition occurred when a 74 µm membrane was used. This result suggested that touching or close physical interaction is needed for toxin inhibition and the nutrient competition hypothesis was not supported. …

Vegetation Structure And Heavy Metal Uptake By Plants In The Mining-Impacted And Non Mining-Impacted Sites Of Southern Lake Victoria Wetlands, G. Y. S. Mtui, C. Mligo, M. K. D. Mutakyahwa, J. R. Ikingura

Tanzania Journal of Science

This study assessed the plant species composition and the heavy metal uptake by plants in the mining-impacted and non mining-impacted areas of the southern Lake Victoria basin. The vegetation of the wetlands was stratified into riverine forest, riverine thickets, swampy grassland, open woodland and floodplain grassland. Plant diversity at Nyamtukuza ranged between 2.34 to 2.70; at Geita was 2.29 to 2.57 and Mwakitolyo was between 1.08 to 1.70, which was significantly lower than the other two sites; whereas variation in plant species richness was not significant. TWINSPAN classification resulted into four clusters of the vegetation communities. Cluster A, a shrubby …

Farmers' Perceptions Of Importance, Control Practices And Alternative Hosts Of Maize Stemborers In Uganda, T. Kalule, Z. R. Khan, G. Bigirwa, J. Alupo, S. Okanya, J. A. Pickett, L. J. Wadhams

All Peer-Reviewed Publications

A survey was conducted in Tororo, Bugiri and Kapchorwa districts in eastern and northeastern Uganda on farmers' perceptions of constraints in maize production. Farmers in Tororo and Bugiri consistently ranked stemborers and striga as the major production constraints in maize growing, while those in Kapchorwa ranked stemborers and lack of capital as the most important. Approximately 35 and 40% of the farmers in Tororo and Bugiri, respectively, identified stemborers as the 'caterpillar' that destroys their maize. In Kapchorwa, 50% of the farmers identified stemborers. Pesticide application was the most common control measure while the use of indigenous and cultural control …