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Graduate Theses and Dissertations

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Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw Dec 2023

Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw

Graduate Theses and Dissertations

Much of the landscape of the United States has been altered by humans, leading to the eradication of most populations of large mammalian predators. Consequently, many species of mammalian mesopredators (medium-sized mammalian predators) have come to dominate the landscape. Species such as the gray fox (Urocyon cinereoargenteus) may appear to be on the rise and doing well due to their widespread range, but at a local scale may need monitoring and less is known in areas of its range. Others such as the plains spotted skunk have a wide range across the plains but are on the decline even with …


Exploring The Interrelationships Among Structural Complexity, Multi-Trophic Biodiversity, And Ecosystem Productivity In Forested Ecosystems., Ayanna St. Rose Dec 2023

Exploring The Interrelationships Among Structural Complexity, Multi-Trophic Biodiversity, And Ecosystem Productivity In Forested Ecosystems., Ayanna St. Rose

Graduate Theses and Dissertations

Forests play a pivotal role in sustaining global biodiversity and mitigating the global climate, as they serve as the primary refuge for terrestrial biodiversity and effectively capture and store atmospheric carbon dioxide. However, changing climate and land use are altering the geographic distribution, physical structure, and productivity of forested ecosystems that can have profound impacts on biodiversity conservation, forest productivity, and global climate. This dissertation contributes to our understanding of multifaceted interactions between the physical and biological structural complexity and ecosystem functions in forested landscapes across the United states by using openly available data from two national networks: the National …


Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker Dec 2023

Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker

Graduate Theses and Dissertations

The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …


Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa Dec 2023

Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa

Graduate Theses and Dissertations

As a result of the advancement of genetics, understanding broiler requirements for dietary energy and amino acids is essential for improving live performance and carcass characteristics. The energy system used to formulate diets in poultry is based on metabolizable energy (ME); this equation can be described as the total amount of energy in the feed minus gases and feces. However, the net energy (NE) system may be the best depiction of the energy utilized by birds for production and maintenance purposes once the heat increment (HI) is measured. Thus, a series of studies were conducted to establish the responsiveness of …


Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson Dec 2023

Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson

Graduate Theses and Dissertations

Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …


Age, Size, And Composition Of Selected Old-Growth Shortleaf Pine Stands In The Upper Buffalo River, Arkansas, Willa Avery Thomason Dec 2023

Age, Size, And Composition Of Selected Old-Growth Shortleaf Pine Stands In The Upper Buffalo River, Arkansas, Willa Avery Thomason

Graduate Theses and Dissertations

Shortleaf pine (Pinus echinata) approaches the westernmost limits of its range in the Arkansas Ozarks. Despite heavy logging of shortleaf pine throughout its range during the 19th and 20th centuries, the species was not easily accessible for harvest and transportation in the most rugged areas of the Boston Mountains and, as a result, there are a few extant stands of old-growth shortleaf pine in the region. The shortleaf pine stands in the interior Boston Mountains are unusual in that they exist primarily above bluff lines at topographic breaks in the hardwood canopy and are not disturbed by fire as frequently …


Health Beneficial Effects Of Black Raspberry, Blueberry, And Blackberry Volatile Extracts In Lung And Colon, Inah Gu Dec 2023

Health Beneficial Effects Of Black Raspberry, Blueberry, And Blackberry Volatile Extracts In Lung And Colon, Inah Gu

Graduate Theses and Dissertations

Berries are one of the most consumed fruits in our diet, and rich in dietary fiber, vitamins, minerals, polyphenols, and volatiles. Volatiles are responsible for the aroma of berries, and are widely used in food, perfumery, and cosmetic industries. However, the potential health beneficial effects of berry volatiles have not been extensively studied. Recently, we found that berry volatiles from cranberries, black and red raspberries, strawberries, blueberries, and blackberries have an anti-inflammatory effect on inflamed murine macrophage cells. Since inflammation can develop into many chronic diseases, and berry volatiles can be inhaled or consumed and pass through the lungs or …


Effect Of Onion Peel Bioactive Compounds On Gut Microbiome Of Obese Adults, Saad Al-Din Sifat Dec 2023

Effect Of Onion Peel Bioactive Compounds On Gut Microbiome Of Obese Adults, Saad Al-Din Sifat

Graduate Theses and Dissertations

Obesity, a pervasive global health concern, involves a complex interplay between genetic factors, dietary patterns, and the gut microbiota. Onion peels are rich in polyphenols and known for their antioxidant properties. However, the effects of in-vitro digested onion peel extract has not been investigated thus far. This study therefore assesses the effects of digested bioactive compounds from onion peels, emphasizing gut microbiota shift and metabolites. Onion peel extract (OPE), digested onion peel extract (DOPE), and solid-phase-extracted digested onion peel extracts (SPE-DOPE) were analyzed for total phenolic content (TPC) and antioxidant activity. SPE-DOPE exhibited the highest TPC and antioxidant activity. Fecal …


Solar Cooking Solutions For Haiti, Isaac Mergner Dec 2023

Solar Cooking Solutions For Haiti, Isaac Mergner

Graduate Theses and Dissertations

This study focuses on enhancing the efficiency of solar cooking through the use of solar cookers and heat retention boxes. The research involved testing various cooking vessels and lids in a solar cooking experiment, with a specific focus on the performance of different materials and their heat retention capabilities. The experiment aimed to increase the efficiency of solar cookers, which are popular in developing nations due to their relatively low cost. The findings indicate that the combination of a solar cooker and a heat retention box can significantly improve the cooking process, particularly in areas with limited access to cooking …


The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo Dec 2023

The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo

Graduate Theses and Dissertations

The gastrointestinal tract is crucial for nutrient absorption and immune system functionality. It employs a synergistic approach, merging physical and biochemical defenses, to counteract pathogens that enter through dietary or other external routes. This system also facilitates the breakdown of complex carbohydrates, a process beyond the host's innate capacity. In swine, gut microbiota early colonization plays a significant role in several physiological developments, shaped by a variety of determinants including maternal factors and environmental conditions. In the swine industry, the shift to indoor pig farming enhances efficiency but limits soil interaction, potentially impacting gut microbiota diversity. Additionally, the practice of …


Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter Dec 2023

Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter

Graduate Theses and Dissertations

Frequent off-target movement occurrences to soybean [Glycine max (L.) Merr.], rice (Oryza sativa L.) injury, and a lack of barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] control followed the commercial launch of florpyrauxifen-benzyl in 2018. Florpyrauxifen-benzyl is a synthetic auxin, Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 4 herbicide used for postemergence weed control in rice and labeled for application at 30 g ae ha-1. Previous research documented that soybean was susceptible to injury following spray applications of florpyrauxifen-benzyl at less-than-labeled rates, and certain varieties of rice are less tolerant to spray-applied florpyrauxifen-benzyl at 30 g ae …


Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …


The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins Aug 2023

The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins

Graduate Theses and Dissertations

Zea mays is the most commonly grown grain in the world and is used for animal feed, human consumption, and the creation of other products such as ethanol and bioplastics. Contamination of stored maize with stored grain invaders can lead to loss of revenue, reduced food availability, and potential health complications. Two such storage invaders; the mold mite Tyrophagus putrescentiae and the fungus Aspergillus flavus can work as symbionts within the grain storage system. To determine resulting population growth from this symbiosis, maize was inoculated with three treatments: A. flavus with no mites, T. putrescentiae with no fungus, and both …


Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf Aug 2023

Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf

Graduate Theses and Dissertations

Target spot, caused by the fungus Corynespora cassiicola, was once considered a minor foliar disease of soybean in the US. However, a severe outbreak of target spot occurred in the southeastern U.S in 2016. Due to the lack of information on resistance in soybean cultivars, and the challenges in screening cultivars in the field, a detached leaf assay was developed to evaluate resistance. The objectives of the effort were to 1) develop a greenhouse inoculation method of soybean with C. cassiicola 2) use that method to compare reactions of soybean germplasm lines to target spot 3) collect and characterize isolates …


Toxicity Of Different Insecticides To Sitophilus Oryzae, Tribolium Castaeneum And Tribolium Confusum Infesting Corn, Amina Twaibu Aug 2023

Toxicity Of Different Insecticides To Sitophilus Oryzae, Tribolium Castaeneum And Tribolium Confusum Infesting Corn, Amina Twaibu

Graduate Theses and Dissertations

Corn is an important cereal crop cultivated across various countries, including the United States. Corn serves multiple purposes such as human and livestock food and raw material for industrial processes. Despite being an important crop, corn production faces challenges due to factors such as weather fluctuations and the presence of insect pests and diseases, both in the field and during storage. Among these challenges, insect infestation poses a major threat, as the insect damage not only reduces the quantity and quality of the grain but also renders it unfit for human and animal consumption, leading to a decrease in market …


The Effects Of Pesticide Exposure And Diet On The Health, Reproduction, And Behavior Of Mason Bees (Osmia Spp.), Olivia Mae Kline Aug 2023

The Effects Of Pesticide Exposure And Diet On The Health, Reproduction, And Behavior Of Mason Bees (Osmia Spp.), Olivia Mae Kline

Graduate Theses and Dissertations

Several mason bees (Osmia spp.), such as Osmia lignaria and Osmia cornifrons, are efficient and valuable pollinators in orchards. They can be used to supplement honey bee (Apis mellifera) pollination, to improve yields and reduce costs compared to A. mellifera alone. Osmia spp. encounter many stressors in their environment, which can negatively impact their health and pollination ability. These stressors include pesticide use and habitat loss due to agricultural expansion. Apis mellifera are often used as surrogates for pesticide risk assessment, but different bee species can vary widely in their response to stressors. Therefore, research into the impact of stressors …


Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson Aug 2023

Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson

Graduate Theses and Dissertations

Hunting participation numbers have steadily declined since the 1980s and Generation Z is not engaging in hunting. Hunting is one of the most effective tools for managing wildlife populations and ensuring the success and local ecosystem conservation. Many wildlife stewardship institutions, such as Arkansas Game and Fish Commission in Arkansas, are funded by sales taxes imposed on firearms, ammo, and archery equipment. With a decline in hunting participation, it is imperative state-run wildlife stewardship organizations and other hunting institutions learn the best practices for communicating with younger generations. This study sought to understand Generation Z’s perceptions of hunting and conservation …


Effects Of Supplemental Trace Minerals As Amino Acid Complexed Or Inorganic Sources For Beef Cattle From Receiving Through Finishing, Robin Ashley Cheek Aug 2023

Effects Of Supplemental Trace Minerals As Amino Acid Complexed Or Inorganic Sources For Beef Cattle From Receiving Through Finishing, Robin Ashley Cheek

Graduate Theses and Dissertations

The objective of experiments was to investigate the effects of inorganic or amino acid-complexed sources of trace minerals on health, gain performance, liver mineral concentrations, and carcass characteristics of beef heifers from receiving through finishing. To investigate the effects of inorganic or amino acid-complexed sources of trace minerals (zinc, copper, manganese, and cobalt) on performance and morbidity of beef heifers during the receiving period, crossbred beef heifer calves arriving on 3 delivery dates were used in a 42-day receiving trial. Treatments consisted of supplemental zinc (360 mg/d), copper (125 mg/d), manganese (200 mg/d), and cobalt (12 mg/d) from complexed (Availa-4, …


Investigating And Characterizing Septin Cellular Regulators During Infection Related Development In M. Oryzae, Rinalda Proko Aug 2023

Investigating And Characterizing Septin Cellular Regulators During Infection Related Development In M. Oryzae, Rinalda Proko

Graduate Theses and Dissertations

The fungus Magnaporthe oryzae causes a devastating disease of rice and wheat, called blast, which poses a major threat to food security across the planet. To enter plant tissue, M. oryzae produces a remarkable pressure-generating infection cell called an appressorium, which mechanically ruptures the tough cuticle of host leaves through the application of enormous physical force directed onto a narrow penetration structure emerging from its base. Importantly, appressorium form and functionality depends on the regulated assembly of a toroidal ring-like structure, composed of septins, which forms within its base. Septins are a family of membrane-associated GTP-binding proteins that polymerize into …


Screening A Set Of Tomato Genotypes For Resistance To Bacterial Wilt And A Genomic Wide Association Study And Genomic Prediction For Yield-Related Traits In ‘Lcp 85-384’. I. Sugarcane, Theresa Makawa Phiri Aug 2023

Screening A Set Of Tomato Genotypes For Resistance To Bacterial Wilt And A Genomic Wide Association Study And Genomic Prediction For Yield-Related Traits In ‘Lcp 85-384’. I. Sugarcane, Theresa Makawa Phiri

Graduate Theses and Dissertations

This thesis comprises two studies that focused on screening tomato genotypes for bacterial wilt resistance and a genome-wide association study and genomic prediction for yield-related traits in sugarcane with the aim of contributing to the breeding programs. In the first chapter, 40 tomato accessions from the USDA collection were evaluated for their resistance to Ralstonia solanacearum isolate P822 under controlled greenhouse conditions. The plants were inoculated, and disease symptoms were visually assessed. Disease severity was rated on a scale of 0 to 4, where 0 represented no wilting and 4 indicated complete leaf wilting. Among the tested accessions, five (PI …


The Future Of Public And Private Plant Breeding According To Plant Scientists, Lexie Burris Aug 2023

The Future Of Public And Private Plant Breeding According To Plant Scientists, Lexie Burris

Graduate Theses and Dissertations

Plant breeding has been effective in addressing food insecurity by increasing agricultural yields and productivity. Historically, public plant breeding programs have long-term, integrated approaches to plant breeding research, germplasm enhancement, and variety development, but as funding is reduced the future is less certain as to areas of focus. This survey builds off those before it and asks the next logical question, if a divergence between private and public breeding is taking place, what aspects should each sector focus on? The impetus of this study was to ask opinions of plant breeders globally regarding the direction they believe the public and …


Factors Affecting Food Security And Participation In Food Pantries In The U.S., Alexis Jade Skinner Aug 2023

Factors Affecting Food Security And Participation In Food Pantries In The U.S., Alexis Jade Skinner

Graduate Theses and Dissertations

Given the rise in food inflation, reduction of SNAP benefits, and the increased demand for food pantry participation, a more holistic understanding of potential barriers to obtaining assistance from non-Federally regulated food pantries is warranted. In May of 2022, 625 surveys were administered to low-income participants in the United States who participated in food collection from a food pantry in the previous month. Those participants were asked to select what information they were asked to provide during their visit, including home address, place of employment, Social Security card, driver’s license, household size, blood test, or others. Some forms of the …


Evaluation Of Drought Tolerance In Usda Tomato Germplasm And Genome-Wide Association Study And Genomic Prediction Of Fusarium Wilt Resistance In Common Bean Core Collection, Kenani Edward Chiwina Aug 2023

Evaluation Of Drought Tolerance In Usda Tomato Germplasm And Genome-Wide Association Study And Genomic Prediction Of Fusarium Wilt Resistance In Common Bean Core Collection, Kenani Edward Chiwina

Graduate Theses and Dissertations

Drought stress and Fusarium wilt disease present significant challenges to plant growth and agricultural productivity, particularly affecting crops such as tomato and common beans. To address these issues, researchers have extensively evaluated germplasm collections under field and greenhouse conditions to identify genotypes with drought tolerance and disease resistance. This study aimed to achieve two objectives. Firstly, we conducted a phenotypic evaluation of drought tolerance in USDA tomato germplasm to identify drought-tolerant accessions for future breeding programs targeting enhanced drought tolerance in tomato cultivars. Secondly, we conducted a genome-wide association study (GWAS) and genomic prediction (GP) on USDA common bean germplasm …


Evaluating Mitochondrial Dynamics And Bioenergetics In Patient-Derived Human Induced Pluripotent Stem Cells And Differentiated Derivatives Modeling Leigh Syndrome, Fibi Meshrkey Aug 2023

Evaluating Mitochondrial Dynamics And Bioenergetics In Patient-Derived Human Induced Pluripotent Stem Cells And Differentiated Derivatives Modeling Leigh Syndrome, Fibi Meshrkey

Graduate Theses and Dissertations

Mitochondrial disorders are complex diseases that involve multiple systems and result from mutations and deletions in the mitochondrial genome. Leigh syndrome (LS) is a rare and devastating primary mitochondrial disorder characterized by progressive neuromuscular degeneration. Despite its severe consequences, the clinical genotype pathophysiological underlying LS remains elusive, posing significant challenges for the development of effective therapies. The current study aims to advance our understanding of the pathology and phenotype correlation of LS by evaluating mitochondrial dynamics and bioenergetics in patient-derived human induced pluripotent stem cells (hiPSCs) and their differentiated derivatives, which serve as a reliable model of the disease. Key …


Consumer Valuation Of Rice Quality In Colombia, Juliann Phillips Aug 2023

Consumer Valuation Of Rice Quality In Colombia, Juliann Phillips

Graduate Theses and Dissertations

Rice is a crucial contributor to global food security and is an important staple for over half the world’s population. In Colombia, total rice consumption has grown by 25% in the last decade (2011-2021), reaching 1.9 MMT in 2021, yet in 2021 around 15.5 million Colombians were classified as food insecure. Colombia is the third largest rice producer in Latin America, producing 1.8 million metric tons (milled basis) in 2021. Increasing rice consumption coupled with high levels of food insecurity highlights the necessity that rice markets effectively price rice according to consumer preferences. Therefore, the goal of this study focuses …


The Roles Of Estrogen Receptor Alpha-Interacting Rnas And Exosomes In Breast Cancer, And E-Cadherin In Carcinomas, Brihget Catalina Sicairos-Meza Aug 2023

The Roles Of Estrogen Receptor Alpha-Interacting Rnas And Exosomes In Breast Cancer, And E-Cadherin In Carcinomas, Brihget Catalina Sicairos-Meza

Graduate Theses and Dissertations

Carcinomas are malignancies of epithelial cells and account for >80% of cancer-related deaths. Approximately 75% of breast cancers express estrogen receptor alpha (ERα). ERα promotes breast cancer progression by enhancing cancer cell proliferation. Tamoxifen is commonly used to treat ERα-positive breast cancers but can result in endocrine therapy resistance. The mechanisms underlying endocrine therapy resistance remain elusive. The Du lab recently found that ERα is an RNA-binding protein. However, the significance of the ERα-RNA interaction is unknown. We fractionated ERα-positive MCF7 cells into cytoplasmic and nuclear fractions, followed by immunoprecipitation of ERα with associated RNAs and RNA-sequencing. We identified many …


Unraveling The Biogenesis And Roles Of Iron-Sulfur Proteins During Nitrogen Fixation By Methanosarcina Acetivorans, Jasleen Saini Aug 2023

Unraveling The Biogenesis And Roles Of Iron-Sulfur Proteins During Nitrogen Fixation By Methanosarcina Acetivorans, Jasleen Saini

Graduate Theses and Dissertations

Iron-sulfur (Fe-S) clusters, the ancient cofactors found in proteins across all life forms, play vital roles in numerous cellular processes. Fe-S clusters exhibit structural diversity, ranging from simple to complex forms. Methanogens are anaerobic archaea that produce methane as a metabolic by-product through methanogenesis, a process dependent on numerous Fe-S proteins. Notably, methanogens are capable of fixing nitrogen (diazotrophy) facilitated by the enzyme complex called nitrogenase, which contains both simple and complex Fe-S clusters. While methanogens possess the largest number of Fe-S proteins, the factors involved in Fe-S cluster biogenesis remain largely unknown. Bacteria possess three distinct and well-characterized Fe-S …


Evaluation Of Heat Stress And Dietary Amino Acid Density On Nutrient And Energy Partitioning In Broilers, Jean-Remi Teyssier Aug 2023

Evaluation Of Heat Stress And Dietary Amino Acid Density On Nutrient And Energy Partitioning In Broilers, Jean-Remi Teyssier

Graduate Theses and Dissertations

The simultaneous increase in the global demand for animal-based protein products and the rise in temperature associated with global warming pose important challenges to the poultry industry. Heat stress (HS) occurs when an animal’s heat production (HP) surpasses its capacity to dissipate heat into the surrounding environment, ultimately leading to reduced feed intake (FI) and negative impacts on performance. A better understanding of bird responses to elevated temperatures is required to propose effective nutritional strategies that mitigate the adverse effects of HS. Therefore, this dissertation aimed to characterize the nutritional and physiological mechanisms explaining the loss in performance and carcass …


A Pilot Study Of Students’ Ethical Decision Making And Emotional Intelligence, Casandra K. Cox Aug 2023

A Pilot Study Of Students’ Ethical Decision Making And Emotional Intelligence, Casandra K. Cox

Graduate Theses and Dissertations

Demand for ethical leaders in agriculture is high to meet 21st century goals, while ethics course offerings in land-grant institutions are limited. The purpose of this case study was to establish a baseline of current University of Arkansas Bumpers College of Agriculture, Food and Life Science (Bumpers College) agriculture and natural resource program students’ ethical decision making (EDM), as measured by the DIT-2, and emotional intelligence (EI), as measured by STEM-B and STEU-B, determine if EI mean scores predict EDM, and identify relationships between EDM or EI and demographic characteristics or lifespan experiences. An online survey design with probability sampling …


Investigation Of Consumer Freezing Practices, Condition And Duration On Palatability Of Beef, Elizabeth Sue Neal Aug 2023

Investigation Of Consumer Freezing Practices, Condition And Duration On Palatability Of Beef, Elizabeth Sue Neal

Graduate Theses and Dissertations

The objective of these studies was to determine: the impact of extended periods of frozen storage duration and packaging type on palatability traits of cooked beef steaks from two muscles and the impact of freezing type and storage duration on objective and subjective measures of ground beef palatability traits. In study 1, no differences were elicited from any of the possible interactions (P= 0.95) for SSF or CL: package × muscle × freezing duration, package × muscle, package × duration or muscle × duration. However, freezing duration did impact both SSF (P < 0.01) and CL (P < 0.001). Generally, for both SSF and CL steaks that were frozen for 9-months elicited both the highest SSF values as well as the greatest percentage of CL among all treatments. In comparison, EM was impacted by the interaction (P = 0.059) of packaging type  muscle  freezing duration. Samples from OW GM stored for 9-months elicited the highest percentage of EM while fresh OW LL samples resulted in the lowest. Additionally, expressible moisture was impacted by the interaction (P = 0.047) of muscle  freezing duration. Among all treatments, GM steaks that were frozen for 9-months elicited the highest EM values and fresh LL samples the lowest EM values. Contrastingly, there was no significant difference observed in expressible moisture for the interaction (P  0.18) of package type  freezing duration or for the interaction (P = 0.70) of package type  muscle. Generally, fresh OW GM steaks resulted in the greatest concentration of lipid derived volatile compounds such as aldehydes, hydrocarbons and alcohols which contrasted sensory ratings of trained panelists that indicated oxidized and refrigerator-stale ratings increased as storage time increased for OW steaks. In study 2, The interaction of freezer treatment × storage duration impacted gumminess (P = 0.05), a TPA attribute. In greater detail, samples stored in RF for 6-months resulted in the greatest gumminess values (P < 0.001), while those stored in the CF for 12-months elicited the lowest (P < 0.001). Similarly, flavor development was also impacted by the interaction (P = 0.05) of freezer treatment × storage duration. Three lipid derived compounds were of greatest concentration among RF patties stored for 1-month. In contrast, the interaction of freezer treatment × storage duration elicited no impact on consumer ratings, SF or TBARS. Nonetheless, frozen storage duration impacted TPA, flavor development, consumer ratings, SF and TBARS as a main effect (P < 0.05), especially in regard to tenderness and juiciness. Moreover, beef flavor development, tenderness and juiciness are impacted by freezing duration, muscle, freezer type and packaging, however these factors are not necessarily independent of one another. Furthermore, the retail display period is a critical period for fresh beef steaks, especially when packaged in aerobic conditions. For optimal eating experience, beef products should be stored for extended periods in a vacuum packaging, in a designated freezer that is not opened frequently to allow for optimal air flow regulation and minimize freezer burn to improve tenderness and juiciness.