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Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke 2010 College of William and Mary - Virginia Institute of Marine Science

Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke

Dissertations, Theses, and Masters Projects

Oyster shell for native oyster reef restoration is scarce in Chesapeake Bay and other estuaries (Chapter 1). Consequently, alternative substrates merit consideration in oyster restoration. This dissertation examines the suitability of shell alternatives, including granite, concrete, limestone marl, concrete modules and reefballs with reef surveys and experiments in the Rappahannock and Lynnhaven Rivers of Chesapeake Bay. Oyster recruitment, growth, survival, density, biomass, condition, and disease stress, as well as reef accretion and persistence, were measured. In the Lynnhaven River, intertidal riprap had a mean density of 978 oysters m-2 (165 g AFDM m-2) and peak densities > 2000 oysters m-2 (Chapter ...


Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett 2010 College of William and Mary - Virginia Institute of Marine Science

Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett

Dissertations, Theses, and Masters Projects

Anthropogenic degradation of coastal and estuarine habitats is an ongoing problem facing scientists, natural resource mangers, and the general public. Decreases in habitat quality produce relatively predictable changes in the structure and composition of macrobenthic communities and it has traditionally been assumed that the ecosystem functions of the community change as well. In Chesapeake Bay, the most pervasive cause for the degradation of benthic habitats is the excessive inputs of nutrients that lead to eutrophication and the accumulation of organic matter in the system. Working within this framework, a study was conducted investigating changes in macrobenthic (i.e., secondary) production ...


The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba 2010 College of William and Mary - Virginia Institute of Marine Science

The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba

Dissertations, Theses, and Masters Projects

Zooplankton play a key role in the cycling of dissolved organic matter (DOM) and inorganic nutrients. The factors that affect these processes, however, are not fully understood. I measured the effects of various diets on DOM and inorganic nutrient production by the copepod Acartia tonsa and the heterotrophic dinoflagellate Oxyrrhis marina, and explored the mechanisms of nutrient release from copepods. Copepods feeding on a mixed diet, the preferred diet of most copepods, had significantly lower dissolved organic carbon (DOC), ammonium (NH4+), and total dissolved nitrogen (TDN) release rates compared to feeding on a carnivorous or herbivorous diet. Thus, copepod feeding ...


Physiological And Toxicological Effects Of Pb Plus Cd Mixtures On Rainbow Trout (Oncorhynchus Mykiss) In Soft Acidic Water, Yvonne Kara 2010 Wilfrid Laurier University

Physiological And Toxicological Effects Of Pb Plus Cd Mixtures On Rainbow Trout (Oncorhynchus Mykiss) In Soft Acidic Water, Yvonne Kara

Theses and Dissertations (Comprehensive)

The ability of a metal to cause toxicity in aquatic environments is highly dependant upon the water chemistry, which can influence metal bioavailability. Metal bioavailability is affected by the concentration of the metal, complexation of the metal by organic and inorganic ligands, and by the speciation of the metal. Predictive models of metal toxicity, such as the biotic ligand model (BLM) have mainly focused upon predicting the toxicity of individual metals rather than the toxicity of metals in mixtures, which are more commonly found in contaminated waters. Two metals that are commonly found together are Pb and Cd which can ...


Insights Into The World Of Pea Nodulation Using The Low Nodulator R50, Scott Clemow 2010 Wilfrid Laurier University

Insights Into The World Of Pea Nodulation Using The Low Nodulator R50, Scott Clemow

Theses and Dissertations (Comprehensive)

Cytokinin oxidase (CKX) is the enzyme responsible for the degradation of cytokinin, a class of adenine-based plant hormones that stimulate cell division, among other physiological processes. The pea mutant R50 is characterized by having a pale leaf phenotype, dwarf stature, few lateral roots, low nodule formation, and elevated levels of endogenous cytokinins in its shoots, roots and nodules. When compared to that of the wild-type Sparkle, total CKX activity is low but the transcript levels of PsCKX1 are significantly higher. In this study, I investigated the expression of PsCKX1 throughout the development of a nodule and the localization of PsCKX1 ...


Insights Into Genome Functional Organisation Through The Analysis Of Interaction Networks, Andre Masella 2010 Wilfrid Laurier University

Insights Into Genome Functional Organisation Through The Analysis Of Interaction Networks, Andre Masella

Theses and Dissertations (Comprehensive)

Using computational techniques to identify orthology and operon structure, it is possible to find functional interactions between genes, which, together, define the genetic interactome. These large networks contain information about the relationships between phenotypes in organisms as genes responsible for related abilities are often co-regulated and reasserting of these genes can be detected in the operon structure. However, these networks are too large to analyse by hand In order to practically analyse the networks, a computational tool, gisql, was developed and, using this tool, the connectivity patterns in the genetic interactome can be analysed to understand high-level organisation of the ...


The Pleiotropic Mutant R50 (Sym16): A Link Between Cytokinin And Starch Metabolism May Explain Its Seed Phenotype, Chengli Long 2010 Wilfrid Laurier University

The Pleiotropic Mutant R50 (Sym16): A Link Between Cytokinin And Starch Metabolism May Explain Its Seed Phenotype, Chengli Long

Theses and Dissertations (Comprehensive)

Cytokinins are a class of adenine-based plant hormones that stimulate cell divisions and are therefore essential for organ growth and development. The role that cytokinin plays in nodulation and that of R50 (syml6) in particular is very complex. In this study, a cytokinin antagonist and a cytokinin oxidase (CKX) inhibitor were used as tools to study the effects of cytokinin perception or cytokinin degradation on nodulation in pea, the cytokinin transduction pathway, especially that induced by CRE1/AHK4, and CKX play a significant role in pea nodulation. Comparison of the full length sequences PsCKX2 cDNAs from Sparkle and R50 indicated ...


Phocine Distemper Virus Induced Demyelination In The Spinal Cord Of Infected Harbor Seals (Phoca Vitulina), Thomas Siemens 2010 University of New England

Phocine Distemper Virus Induced Demyelination In The Spinal Cord Of Infected Harbor Seals (Phoca Vitulina), Thomas Siemens

All Theses And Dissertations

Phocine Distemper Virus (PDV) is a Morbillivirus that has been responsible for the death of approximately 40,000 phocid seals in the last three decades. The most commonly reported pathology is virally induced demyelination of the cerebrum and brainstem which leaves axons bare and limits their conductivity of action potentials. While these conditions have been studied at length, there is little mention of spinal cord involvement. This study aims to determine whether demyelination found in the brainstem continues into the cervical spinal cord. The results indicate that demyelination in the cervical spinal cord does not occur alongside the brainstem. It ...


Living Soil And Composting: Life’S Lessons In The Learning Gardens, Dilafruz R. Williams, Jonathan Brown 2010 Portland State University

Living Soil And Composting: Life’S Lessons In The Learning Gardens, Dilafruz R. Williams, Jonathan Brown

Educational Leadership and Policy Faculty Publications and Presentations

After we spread the chicken poop, we covered it with hay... the poop was the fertilizer and the hay was the stuff that kept the plants warm. After school l checked the garden. Empty. Nobody. I climbed the fence to check the radishes I had planted. I dug around the radishes. They seemed dead. I grabbed a magnifying glass and looked closely at the leaves. Aphids were chewing all the leaves, like ants or other bugs. I went home worried. Next day I went to check the garden. Something red flashed in my eye. I panicked. "Yhaaaa!" I screamed with ...


Genetic Diversity, Micro Propagation, And Cold Hardiness Of Ilex Glabra (L.) A. Gray, Youping Sun 2010 The University of Maine

Genetic Diversity, Micro Propagation, And Cold Hardiness Of Ilex Glabra (L.) A. Gray, Youping Sun

Electronic Theses and Dissertations

Ilex glabra (L.) A.Gray (inkberry) is a native evergreen shrub with dark green foliage and compact habit. This shrub has gained popularity in the northern landscapes of the United States and more nursery growers would like to produce it. To better understand genetic relationships among inkberry cultivars and breed cold-hardy cultivars for northern nursery growers and landscape specialists, the following projects were conducted. A group of 48 inkberry accessions and two other Ilex species (Ilex crenata Thunb. and I. mutchagara Makino) were studied using amplified fragment length polymorphism (AFLP) markers. A total of 229 markers between 50 and 500 ...


Distillers Grains And Livestock Are Important To Ethanol Energy And Greenhouse Gas Balance, Virgil R. Bremer, Adam J. Liska, Haishun Yang, Daniel T. Walters, Galen E. Erickson, Terry J. Klopfenstein, Richard K. Koelsch, Kenneth G. Cassman 2010 University of Nebraska-Lincoln

Distillers Grains And Livestock Are Important To Ethanol Energy And Greenhouse Gas Balance, Virgil R. Bremer, Adam J. Liska, Haishun Yang, Daniel T. Walters, Galen E. Erickson, Terry J. Klopfenstein, Richard K. Koelsch, Kenneth G. Cassman

Nebraska Beef Cattle Reports

A life cycle assessment of the impact of distillers grains plus solubles (DGS) on mitigation of energy and greenhouse gas (GHG) emissions comparing corn ethanol to gasoline demonstrates the importanceof feeding wet DGS (WDGS) to feedlot cattle to optimize the environmental benefit of ethanol production relative to gasoline. Ethanol produced in Nebraska has a superior environmentalimpact compared to ethanol produced in Iowa or Texas.


Fatty Acid Profile Of Beef From Steers Fed Wet Distillers Grains Plus Solubles (Wdgs) And Vitamin E, Amilton S. de Mello, Chris R. Calkins, Kanae Watanabe, Lasika S. Senaratne, Timothy P. Carr, Galen E. Erickson, Judy A. Driskell 2010 University of Nebraska-Lincoln

Fatty Acid Profile Of Beef From Steers Fed Wet Distillers Grains Plus Solubles (Wdgs) And Vitamin E, Amilton S. De Mello, Chris R. Calkins, Kanae Watanabe, Lasika S. Senaratne, Timothy P. Carr, Galen E. Erickson, Judy A. Driskell

Nebraska Beef Cattle Reports

The aim of this work was to investigate the fatty acid profile of m. teres major (TER) and m. infraspinatus (INF) from steers fed 0 or 40% WDGS (DM basis) with or without 500 I.U. of vitamin E/steer daily for 100 days. Thirty-two steers were allocated to 4 treatments: Corn; Corn + vit. E; 40% WDGS; or 40% WDGS + vit. E. After 7 days of aging, 2 TER and 2 INF muscles were excised from the shoulder clods of each animal. Fatty acids were analyzed from raw TER and INF, pan fried TER and INF, and grilled INF. For ...


Extending Grazing In Heifer Development Systems Decreases Cost Without Compromising Production, Daniel M. Larson, Andrea S. Cupp, Richard N. Funston 2010 University of Nebraska-Lincoln

Extending Grazing In Heifer Development Systems Decreases Cost Without Compromising Production, Daniel M. Larson, Andrea S. Cupp, Richard N. Funston

Nebraska Beef Cattle Reports

Three experiments compared heifer development in the dry lot, grazing either dormant winter range or corn crop residue. Grazing corn residue may reduce pre-breeding gain and in doing so increase age at puberty. Compared to dry lot development, grazing corn residue reduced AI pregnancy rate, but final pregnancy rate was similar for both development tsystems. Calf production and rebreeding efficiency were not affected by the development system. However, grazing corn residue during heifer development reduced cost compared to development in the dry lot. Developing heifers by grazing dormant forage does not affect final pregnancy rate and reduces cost, improving the ...


Comparison Of Feeding Wet Distillers Grains In A Bunk Or On The Ground To Cattle Grazing Native Sandhills Winter Range, Jacqueline A. Musgrave, Leslie Aaron Stalker, Matthew C. Stockton, Terry J. Klopfenstein 2010 University of Nebraska-Lincoln

Comparison Of Feeding Wet Distillers Grains In A Bunk Or On The Ground To Cattle Grazing Native Sandhills Winter Range, Jacqueline A. Musgrave, Leslie Aaron Stalker, Matthew C. Stockton, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Two experiments determined the effects of feeding wet distillers grains with solubles (WDGS), either on the ground or in a bunk, to cattle grazing native Sandhills winter range. In Exp. 1, frequency of supplementation had no effect on cow body weight (BW) or body condition score (BCS). BCS and BW of cows fed in a bunk were improved compared to cows fed on the ground. In Exp. 2, steers fed in a bunk had greater average daily gain than steers fed on the ground. Feeding WDGS on the ground resulted in 13-20% waste and cost between$0.03 and $0 ...


Comparison Of Revalor-Xs Vs. Two Common Implant Strategies In Finishing Steers, Cody A. Nichols, Galen E. Erickson, Judson T. Vasconcelos, Justin J. Sindt, Robert L. Botts, Bill D. Dicke, D.J. Jordon, Robert J. Cooper, Tony L. Scott, Terry J. Klopfenstein 2010 University of Nebraska-Lincoln

Comparison Of Revalor-Xs Vs. Two Common Implant Strategies In Finishing Steers, Cody A. Nichols, Galen E. Erickson, Judson T. Vasconcelos, Justin J. Sindt, Robert L. Botts, Bill D. Dicke, D.J. Jordon, Robert J. Cooper, Tony L. Scott, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

A commercial feedlot experiment was performed to compare the effects of a Component TE-IS/TE-S with Tylan (TE-IS/S) implant strategy to a Component TE-200 with Tylan (TE-200) or a Revalor XS (Rev-XS) single implant strategy on performance and carcass characteristics of feedlot steers. Cattle receiving the TE-IS/S implants and the Rev-XS implant had greater (P < 0.05) final BW and lower F:G (P < 0.05) than the cattle that received the TE-200 treatment. Daily gain was improved (P = 0.04) when comparing TE-IS/S to TE-200, but intermediate for steers that received the Rev-XS treatment. Quality grade categories were unaffected by implant strategy. Cattle given TE-IS/TE-S had a greater number (P < 0.05) of yield grade 1 and 2 carcasses than other implant treatments, while cattle receiving TE-200 had greater (P < 0.01) yield grade 3 and 5 carcasses.


Comparing The Energy Value Of Wet Distillers Grains To Dry Rolled Corn In High Forage Diets, Brandon L. Nuttelman, Matt K. Luebbe, Terry J. Klopfenstein, Joshua R. Benton, Galen E. Erickson 2010 University of Nebraska - Lincoln

Comparing The Energy Value Of Wet Distillers Grains To Dry Rolled Corn In High Forage Diets, Brandon L. Nuttelman, Matt K. Luebbe, Terry J. Klopfenstein, Joshua R. Benton, Galen E. Erickson

Nebraska Beef Cattle Reports

Sixty crossbred steers were used to compare the energy value of wet distillers grains (WDGS) to dry rolled corn (DRC) in high forage diets at three levels. DRC was included at 22.0, 41.0, and 60.0% of the diet (DM), and WDGS was included at 15.0, 25.0, and 35.0% of the diet (DM). Diets were formulated to meet degradable intake protein and metabolizable protein requirements. Cattle consuming WDGS gained more than DRC cattle. Average daily gain increased with increasing levels of DRC and WDGS. The energy value of WDGS was calculated using the National Research ...


Genetic And Phenotypic Parameter Estimates For Feed Intake And Other Traits In Growing Beef Cattle, Kelsey Rolfe, Merlyn K. Nielsen, Calvin L. Ferrell, Thomas G. Jenkins 2010 University of Nebraska-Lincoln

Genetic And Phenotypic Parameter Estimates For Feed Intake And Other Traits In Growing Beef Cattle, Kelsey Rolfe, Merlyn K. Nielsen, Calvin L. Ferrell, Thomas G. Jenkins

Nebraska Beef Cattle Reports

The goal of this study was to estimate genetic and phenotypic parameters for growth, feed intake, feed efficiency, and temperament traits in a mixed-breed composite population of growing beef cattle. Intake and gain:feed (G:F) were moderately heritable; however, residual feed intake (RFI) was more heritable than other measures of feed efficiency. Adjusting RFI and G:F for carcass fatness had little effect on heritability and correlations with remaining traits. Flight speed was moderately heritable and highly repeatable. Flight speed was not highly correlated with measures of intake or feed efficiency. Some small breed effects were observed. High heritability ...


Supplementing Modified Wet Distillers Grains With Solubles To Long Yearling Steers Grazing Native Range, Kelsey Rolfe, Matt K. Luebbe, William A. Griffin, Terry J. Klopfenstein, Galen E. Erickson, Dennis E. Bauer 2010 University of Nebraska-Lincoln

Supplementing Modified Wet Distillers Grains With Solubles To Long Yearling Steers Grazing Native Range, Kelsey Rolfe, Matt K. Luebbe, William A. Griffin, Terry J. Klopfenstein, Galen E. Erickson, Dennis E. Bauer

Nebraska Beef Cattle Reports

Modified wet distillers grains with solubles (MDGS) was supplemented on the ground to yearling steers with access to native range during summer grazing. Supplemented steers had greater ADG than non-supplemented steers and were heavier entering the feedlot. NRC energy equations determined that 1.0 lb supplementation of MDGS replaced 0.74 lb forage during summer grazing. Additionally, these data suggest response to MDGS may exceed response to dried distillers grains with solubles (DDGS) for gain during grazing, based on previous experiments.


Wet Distillers Grains Diets Supplemented With Vitamin E Alter The Mineral Composition Of Beef M. Longissimus Lumborum And M. Psoas Major, Lasika S. Senaratne, Chris R. Calkins, Amilton S. de Mello Jr., Galen E. Erickson 2010 University of Nebraska-Lincoln

Wet Distillers Grains Diets Supplemented With Vitamin E Alter The Mineral Composition Of Beef M. Longissimus Lumborum And M. Psoas Major, Lasika S. Senaratne, Chris R. Calkins, Amilton S. De Mello Jr., Galen E. Erickson

Nebraska Beef Cattle Reports

Crossbred yearlings (n = 90) were allotted to one of 10 diets containing 0, 20 or 40% wet distillers grains (WDG) with or without vitamin E supplementation and distillers solubles (DS). Strip loin and tenderloin steaks were obtained and tested for their mineral (Ca, P, K, Mg, Zn, Fe, Mn, Cu, S, and Na) compositions using atomic absorption spectroscopy. Cattle fed DS diets had higher (P ≤ 0.05) levels of Ca, Fe, P, Mn, and S in strip loins than cattle fed non-DS diets. Feeding DS significantly reduced Mg and Na in tenderloins. Neither WDG nor vitamin E diets significantly affected ...


Intramuscular Tenderness Mapping And Muscle Fiber Directions Of Small Muscles In The Beef Round, Lasika S. Senaratne, Chris R. Calkins, Amilton S. de Mello Jr., Jeremy H. Hinkle, Siroj Pokharel 2010 University of Nebraska-Lincoln

Intramuscular Tenderness Mapping And Muscle Fiber Directions Of Small Muscles In The Beef Round, Lasika S. Senaratne, Chris R. Calkins, Amilton S. De Mello Jr., Jeremy H. Hinkle, Siroj Pokharel

Nebraska Beef Cattle Reports

The intramuscular tenderness variation of m. pectineus (PT), m. sartorius (SR), m. gracilis (GL), m. vastus intermedius (VI), and m. vastus medialis (VM) was investigated. The PT, SR, VI, and VM muscles (n=10 each) were grilled as whole muscles, whereas the GL was grilled after cutting into anterior and posterior regions. Grilled muscles were cut into equal size sections perpendicular to the long axis from proximal to distal. Cores were prepared from each section and Warner-Bratzler shear force (WBSF) was measured. The overall mean WBSF values for PT, SR, VI, GL, and VM were 8.29, 9.79, 10 ...


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