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Evaluating The Impacts Of Respondent Errors In Arms: A Case Of Farm Service Agency Loans, Louise Nicole Mcminn

Graduate Theses and Dissertations

Many studies have used the U.S. Department of Agriculture’s (USDA) Agricultural Resource Management Survey (ARMS) to research various aspects involving the agricultural sector in the United States. Since nonresponse and inaccurate reporting may cause significant bias in statistical analysis, research was conducted to determine the magnitude of response error on the farm debt section of the ARMS Phase III. A multinomial logit model identified demographic, structural, and financial characteristics of FSA Farm Loan Program (FLP) borrowers who refused to indicate if they had end of year farm debt, or who accurately or inaccurately classified their farm operations as having end …

Life Cycle Assessment Of Alternative Swine Management Practices, Prathamesh Avadhut Bandekar

Graduate Theses and Dissertations

Life Cycle Assessments (LCAs) are quantitative analyses of complex systems for evaluation of impacts and risk associated with management decisions. LCAs can be effective tools for determining comparative advantages of management strategies across specific impact concern. In this study, life cycle assessments of pork production management alternatives was performed. The alternative management practices included in this study were production of entire males (boars), use of pens for gestation housing, immunocastration, production without growth promoting antimicrobials, production without growth promoting and preventive antimicrobials, and production without ractopamine. These LCAs evaluated the impact of each management strategy on greenhouse gas emission (GHG), …

Poultry Production Messaging: A Content Analysis Of Three National Newspapers From 1994 To 2014, Stuart Estes

Graduate Theses and Dissertations

Consumers are increasingly concerned with the use of antibiotics and hormones in poultry production, and the news media is the primary way consumers gain knowledge about this subject. This study assessed articles about antibiotic and hormone use in poultry production from the New York Times, USA Today, and the Wall Street Journal from 1994 to 2014. This study employed a content analysis methodology to assess selected articles (n = 139) for key messaging about antibiotic and hormone use in poultry production, article tone, article framing, and article journalistic quality. Data gathered from key messages were assessed for emergent themes that …

Physiological And Nutritional Characterization Of High Yield Soybean, Ryan John Van Roekel

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merr.] grain yields greater than three times the national average have been reported in yield contests. Characterization of soybean in a maximum yield environment is necessary to provide empirical data to support those yield claims and to provide an understanding of the physiological processes at that yield level. From 2011 to 2013, research characterized biomass and N accumulation rates, radiation use efficiency (RUE), leaf N dynamics, the rate of harvest index increase (dry matter allocation coefficient, DMAC), seedfill period (SFP), and grain yield components from Mr. Kip Cullers' contest fields and in small plots at the …

Quality And Safety Attributes Of Sun-Dried Raisins From Afghanistan, Stacy A. Mccoy

Open Access Theses

Raisins are an important export commodity for Afghanistan, however, Afghan packers are challenged to export to markets seeking high quality products due to limited knowledge regarding their quality and safety. To evaluate this, Afghan raisin samples from pre-, semi-, and post-processed raisins were obtained from a raisin packer in Kabul, Afghanistan. The raisins were analyzed and compared to U.S. standards for processed raisins. The samples tested did not meet U.S. import standards for embedded sand, but the process used to clean the raisins is suitable to maintain food safety standards.

Previous Afghan raisin shipments have been rejected from the U.S. …

Management Of Silverleaf Whitefly, Bemisia Argentifolii Bellows And Perring (Hemiptera: Aleyrodidae), Using Non-Crop Companion Plants In Organically-Managed Cantaloupe Systems In South Texas, Ruth Renee Colyer

Theses and Dissertations - UTB/UTPA

Field trials in three separate phases of research were carried out from March, 2010, to August, 2012, to determine the effects of inter-cropping cantaloupe (Cucumis melo var. inodorus) with select non-crop companion plants in an effort to develop organic production strategies for melons in South Texas without the use of pesticides. A research program was designed and initiated to assess the effects of the companion plants and their ability to: 1) attract insect pollinators, and 2) repel or suppress pest species without affecting beneficial natural enemy complexes. The hypotheses were: 1) that organically-managed cantaloupe systems grown with non-crop companion plants …

Evolution Of Food Quality Demand In The Food Service Industry In China: The Case Of Duck, Rachel Alison Carnegie

Open Access Theses

Booming economic growth and rising consumer incomes have impacted food preferences and purchasing behavior in China. At the same time, several internationally publicized food safety incidents, particularly in the animal husbandry sector, have heightened awareness of and concern for food safety and quality in meat and dairy. Rising quality demand and safety concerns have been studied at length in the food retail sector, but also appear to be important in the food service industry. This research uses data from a survey of duck restaurant managers and consumers in Beijing, Shanghai, Chengdu, and Guangzhou to determine preferences and willingness to pay …

Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez

Theses and Dissertations - UTB/UTPA

Soil fertility and plant nutrition is crucial for a better yield and consistent harvest in the Rio Grande Valley for local farmers growing citrus trees. A field of oranges and a field of grapefruits were monitored and nutrition deficiencies were noticed that played an important role during fruit set. Soil samples that were taken throughout the year were analyzed via a carbon dioxide extraction method that mimics the way plants naturally take up nutrients or extract nutrients from every soil type. Macronutrients such as the N, P, K, Na, Ca, Mg and some of the micronutrients (Zn, Fe, Mn, and …

Shrinkage Prediction During Pasta Dehydration, Gina Michelle Bressani

Open Access Theses

Shrinkage models from different fields of study were reviewed. Pasta was used as a model to further develop the hypothesis of predicting shrinkage in terms of the rate of relaxation and the rate of moisture loss. An extended literature review of pasta properties, such as isotherms, diffusivity, glass transition, rheological properties, and shrinkage was conducted. Isotherm and glass transition models were developed from the literature data acquired. Creep was tested with a 25 mm-diameter flat plate at 20 to 40°C at varying moisture content. Viscoelastic properties for the Burgers model for creep were determined, where higher moisture content samples resulted …

Evaluating Economic Impacts Of Switchgrass Harvest Time, Nathanial Elsworth Cahill

Graduate Theses and Dissertations

This thesis deals with cost of production for cellulosic energy crops of switchgrass, miscanthus, and energy sorghum. The first chapter explains the rationale for development of decision support software called Energy Crop Analysis & Planning (ENCAP) and Switchgrass Harvest Date, Yield, Nutrient Removal Estimator (SHYNE). The second chapter examines harvest date implications on yield, nutrient removal, opportunity cost of modified sale dates, and post-harvest storage losses. This harvest date analysis leads to a profit maximizing harvest date from the perspective of the producer. While this harvest date may be optimal for the producer, biorefineries may be interested in sourcing switchgrass …

Sugar And Rice Trade Between The United States And Cuba Trade Potential And Welfare Analysis, Fabian Bloechl

Graduate Theses and Dissertations

After the resignation of President Fidel Castro and forty-five years of the U.S.-trade embargo, the political environment between Cuba and the United States is expected to change. With the Trade Sanction Reform and Export Enhancement Act in 2000, trade sanctions were eased for a while. Future trade between both countries would increase the welfare in both countries. This Thesis has the approach to look at the impacts on the commodities of rice and sugar, and the trade sanctions between the United States and Cuba.

Cuba is a net importer of its food supply; therefore, agriculture and food trade is an …

The Role Of Soil Microorganisms In The Resistance Of Giant Ragweed, Horseweed, And Common Lambsquarters To Glyphosate, Jessica Renee Schafer-Bugg

Open Access Dissertations

Continuous glyphosate use has contributed to an increasing number of problematic glyphosate-resistant (GR) weeds. The mechanism of resistance in many GR weeds is poorly understood, in part, due to a poor understanding of how exactly glyphosate kills a plant. In previous research, the efficacy of glyphosate was demonstrated to be strongly influenced by root invading soil-borne microorganisms. However, this interaction among plants, glyphosate, and soil microorganisms has only been studied in a number of crop plants, but not in weed species. This is surprising since the soil biotic environment has a strong impact on the activity of this important herbicide. …

Genes With Physiological Roles In Callipyge Muscle Hypertrophy, Hui Yu

Open Access Dissertations

Callipyge sheep is an excellent model to study genes regulation in muscle growth since the up-regulation of DLK1 and/or RTL1 results in extreme postnatal muscle hypertrophy in loin and hindquarters. DLK1 and/or RTL1 are the primary inducers of muscle hypertrophy due to the inheritance model for the callipyge phenotype. The overall aim of this dissertation is to study the physiological pathways responding to the up-regulation of DLK1 and / or RTL1 in the hypertrophied muscles. Microarray analysis of gene expression identified 375 genes that were differentially expressed in callipyge semimembranosus. Twenty-five transcripts were further verified by quantitative PCR in two …

Functional Characterization Of Metallothioneins In Arabidopsis And Barley, Nimnara Yookongkaew

Open Access Dissertations

Metalothioneins (MTs) are metal binding proteins that can bind metals such as Cu, Zn, and Cd but the functions of MTs in plants are largely unknown. To understand the function of MTs in Arabidopsis, T-DNA insertion mutants lacking 4 MT genes including MT1a, MT2a, MT2b and MT3 were developed. The quadruple mutant (mt1a/mt2a/mt2b/mt3) showed no visible phenotype under standard growth conditions. However, it accumulated higher Cu in leaves compared to wild type but lower Cu in seeds. Further analysis showed that triple mutants lacking both MT1a and MT2b, which are highly expressed in vascular tissues, had similar …

The Use Of Non-Traditional Technologies To Improve The Efficiency And Sustainability Of Modern Poultry Production, Christopher Pixley

Graduate Theses and Dissertations

Historically, major driving factors for the animal agriculture industry have been efficiency and profitability. As demand for efficient food production has increased, the industry has focused research efforts on ways to improve the rearing process. Current market demands are requiring the industry to abandon some of the traditional tools it has used to maximize productivity. However, developing alternative technologies are available which may fill the void. Unfortunately, these alternatives are less well-described and the beneficial impacts they can have are not fully understood. As the animal agriculture industry matures it is becoming evident that consumers will continue to demand methods …

Using The Ceres-Maize Model To Create A Geographically Explicit Grid Based Estimate Of Corn Yield Under Climate Change Scenarios, Ryan Zachary Johnston

Graduate Theses and Dissertations

The CERES-Maize model was evaluated in its capacity to predict both regional maize yield and water use within the United States Department of Agriculture (USDA) Economic Research Service (ERS) Region 1 between the years 1997-2007. A grid based, geospatially explicit method was developed to express the various rainfed and irrigated maize cultivars grown across the region. Overall, the calibrated model compared well for both physiological and yield parameters, producing significant linear relationships (p

The calibrated and validated CERES-Maize model was used to predict potential evapotranspiration and yield under three IPCC weather scenarios for the year 2050 to evaluate crop production …

Measuring The Energy Required To Dry Rice In Commercial Rice Dryers, Maria Alejandra Billiris

Graduate Theses and Dissertations

The objective of this research was to quantify and assess the energy use and efficiency of commercial cross-flow dryers when drying rice using a range of drying and ambient conditions. First, equations that predict the theoretical energy required to dry rice from any given initial moisture content to a desired final moisture content were developed for several rice cultivars using a semi-theoretical approach to obtain a basis for comparison to calculate energy efficiency. Theoretical energy requirements, expressed as the energy required per unit mass of water removed, increased exponentially as initial moisture content decreased. Additionally, medium-grains required more energy to …

Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr

Open Access Dissertations

The shift to concentrated animal production facilities and increasing rural-urban migration has increased the localized land application of nearly 1 billion tons of manure and biosolids annually. Although these applications provide nutrients and contribute to soil tilth, they also serve as a source for an estimated 49 tons of the natural manure-borne estrogens, 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), and estrone (E1). While these estrogens are critical to endocrine systems, the low concentrations observed in the environment can disrupt endocrine function in non-target organisms, e.g., altering secondary sex characteristics which can lead to changes in wildlife communities.

Research presented here focuses on …

The Impact Of Bovine Spongiform Encephalopathy (Bse) On World Protein Supply, Jarrod Kersey

Graduate Theses and Dissertations

As world population, per capita income and urbanization increase, consumption of meat, poultry, milk and eggs will continue to rise to meet the needs of approximately nine billion people in 2050. Global beef, pig and chicken production and per capita consumption increased between 2000 and 2010, with growth in broiler production and consumption outpacing both beef and swine. The increased production and consumption requires readily available feed ingredients in regions where animal production is rapidly developing. Animal-based protein feed ingredients are often difficult to move from country to country due to real or perceived risk of animal disease. Zoosanitary standards …

Consumer Sensory Preferences And Willingness-To-Pay For Nutraceutical-Rich Fruit, Lydia Lawless

Graduate Theses and Dissertations

Health-oriented juices are prime candidates for the nutraceutical market due to their inherent healthfulness and convenience. Fruits such as açaí berries, blueberries, blackberries, black cherries, Concord grapes, cranberries, and pomegranates are rich in potentially health-supporting polyphenolics, which makes the juices of these fruits attractive for nutraceutical optimization. The compositional, sensory, and stability properties of blueberry, blackberry, and Concord grape juice blends were explored in an extended shelf-life study. Initially, 100% blueberry juice had the highest total monomeric anthocyanins (67.40 mg/100mL), 100% blackberry juice had the highest total phenolics (249.24 mg/100mL), and 100% Concord juice had the highest polymeric color (23.21%). …

The Impact Of Selected Forage Legumes On Cattle Performance, Forage Production, And Soil Quality, And Evaluation Of Legume Persistence Under Grazing, Bradley Edward Briggs

Graduate Theses and Dissertations

Interest in substituting legumes for N fertilizer in beef cattle grazing systems has recently increased with rising fertilizer prices. Legumes are well known for their ability to fix atmospheric N and decrease dependence on input of N fertilizer. However, there are still difficulties associated with legume utilization including establishment and persistence. Two experiments were conducted to evaluate legume performance under herbivory. The objective of Experiment 1 was to compare forage production and beef cattle gains from annual ryegrass [Lolium multiflorum (L.)] and bermudagrass [Cynodon dactylon (L.) Pers.] pastures fertilized with N or overseeded with legumes. Gelbvieh × Angus …

Multifunctionality In U.S. Rice Production: A Logit Analysis In Farmers Participation, Juan Tur Cardona

Graduate Theses and Dissertations

Multifunctional agriculture is particularly fundamental to some working lands conservation policies and programs, such as the Environmental Quality Incentive Program (EQIP), Conservation Security Program (CSP) and Wildlife Habitat Incentive Program (WHIP). Farmers can also be engaged in providing recreational and agri-tourism services such as hunting, fishing, bird-watching, farm tours, petting zoos and hospitality services. Using the Agricultural Resource Management Survey (ARMS) we analyze factors associated with participation in conservation, recreation and agri-tourism activities as a function of farm structure, farm financial measures, production practices, and socio-demographic characteristics of the farm operator. To estimate the functional relationships we estimate a binary …

Subcritical Water Hydrolysis Of Whey Proteins, Ashley Dawn Espinoza

Graduate Theses and Dissertations

Hydrolyzing food by-products is a unique approach to potentially increase by-product value and reduce waste. An abundant by-product of cheese production, whey, contains all essential amino acids and some distinctive peptides with functional and nutraceutical properties. Typically, proteins from whey are tailored for specific uses by chemical or enzymatic hydrolysis; however, subcritical water hydrolysis is a novel alternative used successfully to hydrolyze various substrates. Nevertheless, minimal research exists on: (1) the hydrolysis of whey protein; (2) the incorporation of additives; (3) the hydrolysis of whole whey; and (4) the production of volatiles when using subcritical water hydrolysis.

Therefore, whey protein …

Changing Dairy Market Environment: Effect On Cooperative Organization, Competition, And Price Risk Management: Comparative Analysis Between Germany And The United States, Pieter Vermeersch

Graduate Theses and Dissertations

The dairy market environment in the United States of America and in Europe is changing partially due to a change in policies supporting free markets. The effect of the change in the dairy market environment in the United States and Germany on cooperative organization, competition, and price risk management is elaborated in this thesis by means of a literature survey including governmental documents, industry documents, and published scientific articles. The thesis provides a closer look to the interaction between two players within the dairy market chain, i.e. the farmers and the processors. Both players are confronted with increasing accessibility of …

Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia

Theses and Dissertations - UTB/UTPA

Non-native grasses can modify the soils they invade. This study investigated microbial variation among native and non-native grasses in the Lower Rio Grande Valley. We hypothesized that rhizospheres of non-native grasses would support a higher density of microorganisms; therefore microbial communities of invasive plants would exploit more carbon sources than those of native plants. A second hypothesis stated that Streptomyces bacteria from the rhizosphere of non-native grasses would be better competitors. Samples of grasses, and soil from their respective rhizospheres were obtained in Arroyo City, TX. Results indicated a higher bacterial colony density, total activity and number of substrates utilized …

Evaluation Of Streptomycetes For Biological Control Of Gummy Stem Blight Disease Of Cantaloupe, Shima Chaudhary

Theses and Dissertations - UTB/UTPA

Studies were conducted to evaluate the efficacy of Streptomyces isolates for the biological control of gummy stem blight (GSB) in cantaloupes (Cucumis melo var. ‘Primo’) in south Texas. Plants were monitored for seedling emergence, lesions, mortality and plant growth under laboratory, greenhouse and field conditions. Comparison of treatment groups indicated a significant reduction in plant mortality and enhanced growth of infected plants exposed to three Streptomyces isolates (MA1F4#2, WI1B#5, and MA2A4 #2), which appear to be most effective when used in combination. In all three experiments, GSB infection was associated with a significant reduction in reflectance of near-infrared wavelengths (700-1,100 …