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Turkey Sperm Reside In The Tubular Glands In The Urodeum Following Artificial Insemination, M. R. Bakst, V. Akuffo Jan 2008

Turkey Sperm Reside In The Tubular Glands In The Urodeum Following Artificial Insemination, M. R. Bakst, V. Akuffo

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

A turkey hen in egg production requires 48 h after the last insemination to maximize the number of sperm in the uterovaginal junction sperm-storage tubules. Where the sperm that continue to fill the oviductal spermstorage sites during this 48-h period reside remains unknown. Histological sections of the juncture of the vagina with the urodeum, the central compartment of the cloaca, revealed deep tubular glands containing periodic acid- Schiff-positive secretory material. When examined 36 h after the last artificial insemination, sperm were observed in the lumen of the tubular glands associated with the urodeum. We suggest that sperm reside in the …


Serotonin Localization In The Turkey Vaginal But Not Sperm Storage Tubule Epithelia, M. R. Bakst, V. Akuffo Jan 2008

Serotonin Localization In The Turkey Vaginal But Not Sperm Storage Tubule Epithelia, M. R. Bakst, V. Akuffo

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

Elucidating the cellular and molecular mechanisms regulating sperm selection and transport in the vagina of the hen had been the focus of a limited amount of research over the past decade. New observations indicate the presence of nonneuron endocrine cells in the epithelia lining the lumina of the turkey hen vagina and uterovaginal junction. Although no cells in the vagina or uterovaginal junction surface epithelia exhibited argentaffin staining, typical of cells containing neurosecretory granules, cells restricted to the vaginal and uterovaginal junction but not the sperm storage tubule epithelia were immunoreactive positive to serotonin. We speculate that if released into …


Impact Of Solar Ultraviolet-B On The Proteome In Soybean Lines Differing In Flavonoid Contents, Chenping Xu, Joe H. Sullivan, Wesley M. Garrett, Thomas J. Caperna, Savithiry Natarajan Jan 2008

Impact Of Solar Ultraviolet-B On The Proteome In Soybean Lines Differing In Flavonoid Contents, Chenping Xu, Joe H. Sullivan, Wesley M. Garrett, Thomas J. Caperna, Savithiry Natarajan

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

Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was used to systematically investigate the impact of solar ultraviolet- B (UV-B) radiation on the soybean leaf proteome. In order to investigate the protective role of flavonoids against UV-B, two isolines of the Clark cultivar (the standard line with moderate levels of flavonoids and the magenta line with reduced flavonoids) were grown in the field with or without natural levels of UV-B. The 12-day-old first trifoliates were harvested for proteomic analysis. More than 300 protein spots were reproducibly resolved and detected on each gel. Statistical analysis showed that 67 protein spots were significantly (P < 0.05) affected by solar UV-B. Many more spots were altered by UV-B in the magenta line than in the standard line. Another 12 protein spots were not altered by UV-B but showed significantly (P < 0.05) different accumulations between the two lines, and for most spots the line-specific differences were also observed under UV-B exclusion. Most of the differentially accumulated spots were identified by mass spectrometry. The proteins were quite diverse, and were involved in metabolism, energy, protein destination/storage, protein synthesis, disease/defense, transcription, and secondary metabolism. The results suggest that high levels of flavonoids lead to a reduction in UV-B sensitivity at the proteomic level.


Asas Centennial Paper: Net Energy Systems For Beef Cattle – Cattles, Application, And Future Models, Calvin Ferrell, J. W. Oltjen Jan 2008

Asas Centennial Paper: Net Energy Systems For Beef Cattle – Cattles, Application, And Future Models, Calvin Ferrell, J. W. Oltjen

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

Development of nutritional energetics can be traced to the 1400s. Lavoisier established relationships among O2 use, CO2 production and heat production in the late 1700s, and the laws of thermodynamics and law of Hess were discovered during the 1840s. Those discoveries established the fundamental bases for nutritional energetics and enabled the fundamental entity ME = retained energy + heat energy to be established. Objectives became: 1) to establish relationships between gas exchange and heat energy, 2) to devise bases for evaluation of foods that could be related to energy expenditures, and 3) to establish causes of energy expenditures. …


A Putative Quantitative Trait Locus On Chromosome 20 Associated With Bovine Pathogenic Disease Incidence, E. Casas, G. Snowder Jan 2008

A Putative Quantitative Trait Locus On Chromosome 20 Associated With Bovine Pathogenic Disease Incidence, E. Casas, G. Snowder

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

The objective of this study was to detect QTL associated with the incidence of multiple pathogenic diseases in offspring from half-sib bovine families. Four F1 sires were used to produce offspring: Brahman × Hereford (BH; n = 547), Piedmontese × Angus (PA; n = 209), Brahman × Angus (n = 176), and Belgian Blue × MARC III (n = 246). Treatment records for bovine respiratory disease, infectious keratoconjunctivitis (pinkeye), and infectious pododermatitis (footrot) were available for all of the offspring from birth to slaughter. The incidences of these 3 microbial pathogenic diseases were combined into a single binary trait …


Improvement Of Perennial Forage Species As Feedstock For Bioenergy, William Anderson, Michael Casler, Brian S. Baldwin Jan 2008

Improvement Of Perennial Forage Species As Feedstock For Bioenergy, William Anderson, Michael Casler, Brian S. Baldwin

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

Both native and non-native forage species other than switchgrass are less commonly considered as potential lignocellulosic feedstocks for bioenergy in the United States. These species hold potential as bioenergy feedstocks because of the experience and infrastructure that is already in place for management and harvest, and in certain areas of the country they have greater yield potential than switchgrass or other feedstocks. The forage grasses consist of temperate cool-season (most commonly C3) grasses as well as tropical or sub-tropical warm-season (C4) grasses. Some legume species may also play a significant role in supplying useful bioenergy feedstocks. Most have been researched …


The Artiodactyl Apobec3 Innate Immune Repertoire Shows Evidence For A Multi-Functional Domain Organization That Existed In The Ancestor Of Placental Mammals, Rebecca Larue, Stefán Jónsson, Kevin Silverstein, Mathieu Lajoie, Denis Bertrand, Nadia El-Mabrouk, Isidro Hötzel, Valgerdur Andrésdóttir, Timothy Smith, Reuben Harris Jan 2008

The Artiodactyl Apobec3 Innate Immune Repertoire Shows Evidence For A Multi-Functional Domain Organization That Existed In The Ancestor Of Placental Mammals, Rebecca Larue, Stefán Jónsson, Kevin Silverstein, Mathieu Lajoie, Denis Bertrand, Nadia El-Mabrouk, Isidro Hötzel, Valgerdur Andrésdóttir, Timothy Smith, Reuben Harris

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

Background: APOBEC3 (A3) proteins deaminate DNA cytosines and block the replication of retroviruses and retrotransposons. Each A3 gene encodes a protein with one or two conserved zinccoordinating
motifs (Z1, Z2 or Z3). The presence of one A3 gene in mice (Z2–Z3) and seven in humans, A3A-H (Z1a, Z2a-Z1b, Z2b, Z2c-Z2d, Z2e-Z2f, Z2g-Z1c, Z3), suggests extraordinary evolutionary flexibility. To gain insights into the mechanism and timing of A3 gene expansion and into the functional modularity of these genes, we analyzed the genomic sequences, expressed cDNAs and activities of the full A3 repertoire of three artiodactyl lineages: sheep, cattle and pigs.
Results: …


Chapter 15. Proven Practices And Innovative Technologies For On-Farm Crop Nitrogen Management, N. R. Kitchen, K. W. T. Goulding, J.F. Shanahan Jan 2008

Chapter 15. Proven Practices And Innovative Technologies For On-Farm Crop Nitrogen Management, N. R. Kitchen, K. W. T. Goulding, J.F. Shanahan

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

Nitrogen (N) from soil, fertilizer, and manure sources is generally inefficiently used (30-60%) in most crop production systems. As a consequence, unused inorganic N can move off crop fields and contaminate surface and groundwater resources. Local and national governments have responded with guidelines, standards, regulations, and in some cases fines when off-field losses of N have not been reduced. Along with these environmental pressures, soaring energy costs have resulted in commensurate increased costs for N fertilizers. These factors are real for crop producers and are compelling them to scrutinize their crop N management more closely than in previous decades. Numerous …


Chapter 4. Relationship Of Environmental Nitrogen Metabolism To Human Health, J. R. Follett, R. F. Follett Jan 2008

Chapter 4. Relationship Of Environmental Nitrogen Metabolism To Human Health, J. R. Follett, R. F. Follett

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

The need for humans to produce and consume food and other agricultural products is increasing. This need is directly related to increasing world populations, demands for goods and services, and expectations. Nitrogen (N) is contained in all of the amino acids and proteins in the foods consumed by humans. The use of N to produce food and other products is generally increasing as human needs increase. Proteins are an essential component of the human diet because, unlike plants, humans are unable to utilize more simple forms of N and rely on food sources for protein which can then be digested …


The First Five Years Of The Conservation Effects Assessment Project, Lisa F. Duriancik, Dale Bucks, James P. Dobrowolski, Tom Drewes, S. Diane Eckles, Leonard Jolley, Robert L. Kellogg, Daryl Lund, Joseph R. Makuch, Michael P. O’Neill, Charles A. Rewa, Mark R. Walbridge, Roberta Parry, Mark A. Weltz Jan 2008

The First Five Years Of The Conservation Effects Assessment Project, Lisa F. Duriancik, Dale Bucks, James P. Dobrowolski, Tom Drewes, S. Diane Eckles, Leonard Jolley, Robert L. Kellogg, Daryl Lund, Joseph R. Makuch, Michael P. O’Neill, Charles A. Rewa, Mark R. Walbridge, Roberta Parry, Mark A. Weltz

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

The Conservation Effects Assessment Project (CEAP) was initiated by the USDA Natural Resources Conservation Service (NRCS), Agricultural Research Service (ARS), and Cooperative State Research, Education, and Extension Service (CSREES) in response to a general call for better accountability of how society would benefit from the 2002 farm bill’s substantial increase in conservation program funding (Mausbach and Dedrick 2004). The original goals of CEAP were to establish the scientific understanding of the effects of conservation practices at the watershed scale and to estimate conservation impacts and benefits for reporting at the national and regional levels. Other federal agencies and nongovernmental organizations …


Screwworms, Cochliomyia Hominivorax, Reared For Mass Release Do Not Carry And Spread Foot-And-Mouth Disease Virus And Classical Swine Fever Virus, M. F. Chaudhury, G. B. Ward, Steven R. Skoda, M. Y. Deng, J. B. Welch, T. S. Mckenna Jan 2008

Screwworms, Cochliomyia Hominivorax, Reared For Mass Release Do Not Carry And Spread Foot-And-Mouth Disease Virus And Classical Swine Fever Virus, M. F. Chaudhury, G. B. Ward, Steven R. Skoda, M. Y. Deng, J. B. Welch, T. S. Mckenna

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

Experiments were done to determine if transporting live screwworms Cochliomyia hominivorax Coquerel (Diptera: Calliphoridae) for developing new strains from countries where foot-and-mouth disease and classical swine fever are endemic, to the mass rearing facilities in Mexico and Panama, may introduce these exotic diseases into these countries. Are screwworms capable of harboring and spreading foot-and-mouth disease virus (FMDV) and classical swine fever virus (CSFV) when they are grown in virus-inoculated larval rearing medium? In one experiment, screwworm larvae were reared in a FMDV-inoculated artificial medium containing either 0.1% formaldehyde. In each experiment, samples of larvae and the rearing media were collected …


Auditing And Assessing Air Quality In Concentrated Feeding Operations, N. A. Cole, R. Todd, B. Auvermann, D. B. Parker Jan 2008

Auditing And Assessing Air Quality In Concentrated Feeding Operations, N. A. Cole, R. Todd, B. Auvermann, D. B. Parker

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

The potential adverse effects of concentrated animal feeding operations (CAFO) on the environment are a growing concern. The air quality issues of most concern to CAFO vary but generally include ammonia, hydrogen sulfide, particulate matter, volatile organic compounds, greenhouse gases, and odors. Air pollutants may be regulated by federal and state laws or by nuisance complaints. The United States Environmental Protection Agency, and poultry, swine, and dairy industries recently agreed to the National Air Emissions Monitoring System to fund research on atmospheric emissions from production farms in the United States. Air quality regulations may be based on actual emissions, atmospheric …


Pollen From The Exoskeletons Of Stable Flies, Stomoxys Calcitrans (Linnaeus 1758), In Gainesville, Florida, U.S.A., David M. Jarzen, Jerome Hogsette Jan 2008

Pollen From The Exoskeletons Of Stable Flies, Stomoxys Calcitrans (Linnaeus 1758), In Gainesville, Florida, U.S.A., David M. Jarzen, Jerome Hogsette

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

Stable flies are an important pest of humans and livestock. Despite being blood feeders, they also visit flowers to eat nectar. Stable flies with pollen adhering to their exoskeletons were collected at the University of Florida Horse Teaching Unit and taken to the Paleobotany and Palynology Laboratory at the Florida Museum of Natural History for processing and identification. The pollen on all the specimens was identified as Carolina willow, Salix caroliniana Michaux 1803. This small shrub or tree is found throughout Florida in wetland areas. This study demonstrates the utility of pollen analysis in interdisciplinary studies.


Aged Switchgrass Seed Lot's Response To Dormancy-Breaking Chemicals, Gautam Sarath, Robert B. Mitchell Jan 2008

Aged Switchgrass Seed Lot's Response To Dormancy-Breaking Chemicals, Gautam Sarath, Robert B. Mitchell

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

Aged switchgrass seed lots can display various levels of dormancy. Under-standing the causes for this dormancy will provide better insight into seed physiology, and potentially lead to treatments that reduce variability in seed germination assays. The effects of sodium nitroprusside, potassium ferro-cyanide and hydrogen peroxide on the germination of eight aged switch-grass (Panicum virgatum L.) seed lots, seven of which were produced in the same year at a single experiment station, were examined. Seed germination demonstrated a significant seed lots × days and treatments × days effect. However, responses of individual seed lots to specific chemicals varied considerably. Genetically …


Synthesis And Bioassay Of Improved Mosquito Repellents Predicted From Chemical Structure, Alan R. Katritzky, Zuoquan Wang, Svetoslav Slavov, Maia Tsikolia, Dimitar Dobchev, Novruz G. Akhmedov, C. Dennis Hall, Ulrich R. Bernier, Gary G. Clark, Kenneth Linthicum Jan 2008

Synthesis And Bioassay Of Improved Mosquito Repellents Predicted From Chemical Structure, Alan R. Katritzky, Zuoquan Wang, Svetoslav Slavov, Maia Tsikolia, Dimitar Dobchev, Novruz G. Akhmedov, C. Dennis Hall, Ulrich R. Bernier, Gary G. Clark, Kenneth Linthicum

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

Mosquito repellency data on acylpiperidines derived from the United States Department of Agriculture archives were modeled by using molecular descriptors calculated by CODESSA PRO software. An artificial neural network model was developed for the correlation of these archival results and used to predict the repellent activity of novel compounds of similar structures. A series of 34 promising N-acylpiperidine mosquito repellent candidates (4a–4q’) were synthesized by reactions of acylbenzotriazoles 2a–2p with piperidines 3a–3f. Compounds (4a–4q’) were screened as topically applied mosquito repellents by measuring the duration of repellency after application to cloth patches worn on the arms of human volunteers. Some …


Enteric Bacteria Of Field-Collected Colorado Potato Beetle Larvae Inhibit Growth Of The Entomopathogens Photorhabdus Temperata And Beauveria Bassiana, Michael B. Blackburn, Dawn E. Gundersen-Rindal, Donald C. Weber, Phyllis A. W. Martin, Robert R. Farrar Jr. Jan 2008

Enteric Bacteria Of Field-Collected Colorado Potato Beetle Larvae Inhibit Growth Of The Entomopathogens Photorhabdus Temperata And Beauveria Bassiana, Michael B. Blackburn, Dawn E. Gundersen-Rindal, Donald C. Weber, Phyllis A. W. Martin, Robert R. Farrar Jr.

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

The nematode Heterorhabditis marelatus fails to reproduce in the Colorado potato beetle, Leptinotarsa decemlineata, possibly due to interference from the enteric bacteria of the beetle. Specifically, the enteric bacteria inhibit the growth of Photorhabdus temperata, the enteric symbiont of the nematode, in vitro. However, previous work was based on a laboratory culture of L. decemlineata, and we wished to determine if similar bacteria were present in the field. Therefore, we cultured the enteric bacteria of fourth-instar larvae collected from the field at two locations in Maryland and Virginia. Representatives of the genera Pantoea, Enterobacter, Pseudomonas …


Comparison Of Nitrogen Fertilization Methods And Rates For Subsurface Drip Irrigated Corn In The Semi-Arid Great Plains, D. D. Tarkalson, J. O. Payero Jan 2008

Comparison Of Nitrogen Fertilization Methods And Rates For Subsurface Drip Irrigated Corn In The Semi-Arid Great Plains, D. D. Tarkalson, J. O. Payero

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

In semi‐arid areas such as western Nebraska, interest in subsurface drip irrigation (SDI) for corn is increasing due to restricted irrigation allocations. However, crop response quantification to nitrogen (N) applications with SDI and the environmental benefits of multiple in‐season (IS) SDI N applications instead of a single early‐season (ES) surface application are lacking. The study was conducted in 2004, 2005, and 2006 at the University of Nebraska‐Lincoln West Central Research and Extension Center in North Platte, Nebraska, comparing two N application methods (IS and ES) and three N rates (128, 186, and 278 kg N ha-1) using a …


A Core Set Of Microsatellite Markers For Western Corn Rootworm (Coleoptera: Chrysomelidae) Population Genetics Studies, Kyung Seok Kim, Uwe Stolz, Nicholas J. Miller, Miller R. Waits, Thomas Guillermaud, Douglas V. Sumerford, Thomas W. Sappington Jan 2008

A Core Set Of Microsatellite Markers For Western Corn Rootworm (Coleoptera: Chrysomelidae) Population Genetics Studies, Kyung Seok Kim, Uwe Stolz, Nicholas J. Miller, Miller R. Waits, Thomas Guillermaud, Douglas V. Sumerford, Thomas W. Sappington

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

Interest in the ecological and population genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, has grown rapidly in the last few years in North America and Europe. This interest is a result of a number of converging issues related to the increasing difficulty in managing this pest and the need to characterize and understand gene ßow in the context of insect resistance management. One of the key components needed for successful population genetics studies is the availability of suitable molecular markers. Using a standard group of microsatellite markers enables researchers from different laboratories to directly compare and share …


Using The Solvent Retention Capacity Test When Breeding Wheat For Diverse Production Environments, Carl Walker, Kimberly A. Garland-Campbell, Brady Carter, Kimberlee Kidwell Jan 2008

Using The Solvent Retention Capacity Test When Breeding Wheat For Diverse Production Environments, Carl Walker, Kimberly A. Garland-Campbell, Brady Carter, Kimberlee Kidwell

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

The solvent retention capacity (SRC) test is used to predict commercial baking performance of soft wheat (Triticum aestivum L.) by measuring the capacity of fl our to retain each of four solvents— water, Na2CO3, sucrose, and lactic acid— to assess overall absorption capacity, starch damage, pentosan and gliadin content, and glutenin quality, respectively. Our objectives were to determine sources of variation in the test, repeatability, and optimum scale and resource allocation needed to maximize efficiency. Duplicate SRC tests were conducted for each solvent using two flour sample sizes (5 and 0.2 g) from two field …


Using The Solvent Retention Capacity Test When Breeding Wheat For Diverse Production Environments, Carl Walker, Kimberly A. Garland-Campbell, Brady Carter, Kimberlee Kidwell Jan 2008

Using The Solvent Retention Capacity Test When Breeding Wheat For Diverse Production Environments, Carl Walker, Kimberly A. Garland-Campbell, Brady Carter, Kimberlee Kidwell

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

The solvent retention capacity (SRC) test is used to predict commercial baking performance of soft wheat (Triticum aestivum L.) by measuring the capacity of flour to retain each of four solvents— water, Na2CO3, sucrose, and lactic acid— to assess overall absorption capacity, starch damage, pentosan and gliadin content, and glutenin quality, respectively. Our objectives were to determine sources of variation in the test, repeatability, and optimum scale and resource allocation needed to maximize efficiency. Duplicate SRC tests were conducted for each solvent using two flour sample sizes (5 and 0.2 g) from two field replications …