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2022

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Evaluation Of Novel Litter Amendments For Use In The Commercial Broiler Industry, Jorge A. Urrutia Dec 2022

Evaluation Of Novel Litter Amendments For Use In The Commercial Broiler Industry, Jorge A. Urrutia

Theses and Dissertations

Poultry litter amendments (LA) are commonly used to maintain good litter quality; the most common ones; are acidifiers. However, concern over the lifespan of LA acidifiers (d) and corrosive nature revealed a need for alternative LA. Products of interest include biochar (BC), superabsorbent polymers (SAPs), and alum mud (AM). Experiment 1 was a screening study (n=17 treatments, no birds) conducted to determine the optimal application rate/method of BC, SAPs, and AM vs.commercial LA and a control. Most SAPs treatments measured metrics may be similar (i.e., bacteria, water activity) or better (pH) vs. commercial LA (PLT). High inclusions of novel LA …


Non-Traditional Adjuvants And Methods For Applying Root-Promoting Compounds In Commercial Cutting Propagation, Anthony Turner Bowden Dec 2022

Non-Traditional Adjuvants And Methods For Applying Root-Promoting Compounds In Commercial Cutting Propagation, Anthony Turner Bowden

Theses and Dissertations

The nursery/greenhouse industry is innovative. There have been several reports in the popular literature of non-traditional adjuvants used in plant propagation; however, these claims have never been evaluated in a scientific setting. Five studies, conducted at the South Mississippi Branch Experiment Station in Poplarville in 2019 and 2021 determined the impact that adding honey to water-soluble auxin solutions and surfactants to foliar applied auxin solutions on physiological responses associated with adventitious root formation. Treatments in studies presented in chapters two and three included three honey sources (multiflora, local, and Manuka). Honey-infused water-soluble auxin solutions affected plant species but not in …


Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers Dec 2022

Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers

Theses and Dissertations

A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …


Assessment Of Simulated And Real-World Autonomy Performance With Small-Scale Unmanned Ground Vehicles, William Peyton Johnson Dec 2022

Assessment Of Simulated And Real-World Autonomy Performance With Small-Scale Unmanned Ground Vehicles, William Peyton Johnson

Theses and Dissertations

Off-road autonomy is a challenging topic that requires robust systems to both understand and navigate complex environments. While on-road autonomy has seen a major expansion in recent years in the consumer space, off-road systems are mostly relegated to niche applications. However, these applications can provide safety and navigation to dangerous areas that are the most suited for autonomy tasks. Traversability analysis is at the core of many of the algorithms employed in these topics. In this thesis, a Clearpath Robotics Jackal vehicle is equipped with a 3D Ouster laser scanner to define and traverse off-road environments. The Mississippi State University …


Alteration Of The Viral Immune Response In The Lung Of Juvenile Rats By Cannabidiol, Kylee J. Burroughs Dec 2022

Alteration Of The Viral Immune Response In The Lung Of Juvenile Rats By Cannabidiol, Kylee J. Burroughs

Theses and Dissertations

Cannabidiol (CBD) has unverified use in the treatment of ADHD but parents are giving CBD to their children to treat hyperactivity and restlessness. CBD has suppressive effects on immune function therapeutically but the effect of pre-exposure to CBD on the response to an immune challenge is unknown. To investigate this, male and female juvenile rats were treated orally with either corn oil or 20 mg/kg or 60 mg/kg CBD daily for 5 days followed 24 hours later by intranasal challenge with a viral mimic, Resiquimod (R848). After 6 hours, lungs were collected for the analysis of gene expression of select …


Assessing The Legacy Of Erosion And Flood Control Management Efforts On The Fish Assemblages And Physical Conditions Of Yazoo Basin Bluff Hill Streams, Nicky M. Faucheux Dec 2022

Assessing The Legacy Of Erosion And Flood Control Management Efforts On The Fish Assemblages And Physical Conditions Of Yazoo Basin Bluff Hill Streams, Nicky M. Faucheux

Theses and Dissertations

The hills of Yazoo Basin have a long history of land use modification and subsequent erosion and flood control issues. In response, federal actions were taken to address these issues beginning after the Mississippi River flood of 1927. Four major flood control reservoirs were built in 1932-1957, and instream low-drop grade control structures (GCS) were installed beginning in the 1980s. The objective of my dissertation was to ascertain the long-term effects of these efforts on stream fish assemblages and channel morphology. To assess whether the reservoirs affected upstream fish assemblages as barriers to recolonization by fluvial fishes or as source …


Oxidized Fibrin Alginate Microbeads To Treat Vascular Calcification, Brittany Nichole Macha Dec 2022

Oxidized Fibrin Alginate Microbeads To Treat Vascular Calcification, Brittany Nichole Macha

Theses and Dissertations

Calcification is linked to a high prevalence of cardiovascular events and mortality due to arterial stiffness. Stiffening of the arteries in the case of medial calcification is due to hydroxyapatite mineral deposited in the artery thus leading to the loss of elastin. A possibility of removing this rogue mineral along the vessel walls could be the use of osteoclasts. Osteoclasts, a type of osteocyte, have the unique ability to absorb bone in the bone turnover process. It is proposed that in the future, osteoclasts be delivered to the site of mineralization through oxidized alginate-fibrin microbeads. Alginate hydrogels have proven great …


Ex Vivo Biomechanical Comparison Of Four Center Of Rotation Angulation Based Leveling Osteotomy Fixation Methods, Melody E. Whitney Dec 2022

Ex Vivo Biomechanical Comparison Of Four Center Of Rotation Angulation Based Leveling Osteotomy Fixation Methods, Melody E. Whitney

Theses and Dissertations

Thirty-two canine tibiae with patellae and patellar tendons were harvested from 17 skeletally mature cadavers. Each tibia was randomly allocated to a construct group: plate and pin (Plate), plate with countersink compression screw (HCS), plate with tension band (TB), or plate with HCS and TB (HCSTB). Samples were loaded by distraction until failure. The stiffness, yield load, and ultimate load were compared between each fixation method. No difference in stiffness of the constructs was detected between groups. Yield load and ultimate load for the HCSTB group was greater than the TB group, the HCS group, and the Plate group. CBLO …


Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur Dec 2022

Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur

Theses and Dissertations

Sustainable practices were evaluated for the production of two warm season vegetable crops, tomato and chile peppers. The first study investigated the plant vegetative growth, fruit production timing, yield components and fruit quality of three hybrid and three heirloom tomato cultivars grown in a high tunnel using grafted and non-grafted plants. Grafting the selected tomato cultivars with the two rootstock types did not alter total marketable yield of any cultivar, but affected overall stem diameter, fruit color, and β-carotene concentrations of tested tomato cultivars. The second study evaluated the plant growth, yield, and fruit quality of nine heirloom chile pepper …


The Use Of 87sr/86sr Isotopic Ratios To Assess Natal Areas And Movement Of Juvenile Gulf Sturgeon Acipenser Oxyrinchus Desotoi In The Pascagoula And Pearl River Systems, Joshua Neary Dec 2022

The Use Of 87sr/86sr Isotopic Ratios To Assess Natal Areas And Movement Of Juvenile Gulf Sturgeon Acipenser Oxyrinchus Desotoi In The Pascagoula And Pearl River Systems, Joshua Neary

Theses and Dissertations

The effects of water and dietary influence, and time duration for discernment, of pectoral fin spine 87Sr/86Sr were evaluated in Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus. Fish were subjected to 87Sr-enriched water (0.1 mg/L) or diet (0.25 migrogram/g or 0.5 microgram/g) for 1, 2, 3, 6, or 12 weeks. Fish were also held at 15 or 25°C to determine if temperature influenced 87Sr/86Sr. Results found fin spine 87Sr/86Sr changed in water after 1 week and diet after 12 weeks suggesting water is the primary influence. In wild Gulf Sturgeon A. o. …


Development Of A Novel Loop-Mediated Isothermal Amplification (Lamp) Assay For The Rapid Detection Of Clostridium Perfringens, Deepa Chaudhary Dec 2022

Development Of A Novel Loop-Mediated Isothermal Amplification (Lamp) Assay For The Rapid Detection Of Clostridium Perfringens, Deepa Chaudhary

Theses and Dissertations

Clostridium perfringens (C. perfringens) causes diseases such as necrotic enteritis in poultry. Current methods for early detection of C. perfringens, including culture, and molecular techniques (PCR and qPCR), have logistical limitations in detecting pathogens on-site because they require specialized equipment and long sample preparation time. This study describes developing a highly sensitive on-site LAMP assay combined with a simple DNA extraction method to detect C. perfringens. Results showed that the LAMP assay was highly specific and sensitive with the optimal reaction conditions: 63°C for 30 mins with primer concentration of 1.2 mM FIP/BIP and 0.2 mM F3/B3. The HotSHOT method …


An Inventory And Analysis Of Human Remains From The Aklis Site (12vam1-42) Curated At Mississippi State University, Kaelyn Olson Dec 2022

An Inventory And Analysis Of Human Remains From The Aklis Site (12vam1-42) Curated At Mississippi State University, Kaelyn Olson

Theses and Dissertations

This project was an inventory and analysis of human remains from the Aklis archaeological site (12VAm1-42), located in the Sandy Point National Wildlife Refuge, St. Croix, U.S. Virgin Islands. The human remains inventoried during this project were collected by the U.S. Fish and Wildlife Service and MSU during surface collection and emergency salvage excavations at Aklis. The statistical analysis of the data focused on the minimum number of individuals (MNI) per square meter, the degree of long bone completion, skeletal element counts across excavated features, and the degree of weathering. Results indicate that the assemblage curated at MSU includes a …


Establishing The Relationship Between Broiler Beak Size, Starter Feed Particle Size Selection And Performance, Maria Jose Alvarenga Ramirez Dec 2022

Establishing The Relationship Between Broiler Beak Size, Starter Feed Particle Size Selection And Performance, Maria Jose Alvarenga Ramirez

Theses and Dissertations

Starter feed particle size (FPS) is typically small (~1200 µm) due to bird beak capacity (BC). Recent research has found that chicks can consume a larger FPS than previously thought; however, preferred FPS and its relationship with BC has not been established. Experiment 1 was conducted to determine the effect of breeder flock age (BFA) and feeding strategy (FS) on 0-14 d performance, BC and FPS preference. These data found that BC was dependent upon BFA and FPS consumed was dependent upon FS. Also, chicks could consume increased FPS without impacting starter performance; thus Experiment 2 was conducted to determine …


Efficacy Of Antimicrobial Treatments In Vitro And On Fresh Produce Against Selected Foodborne Pathogens And Microbiome Diversity Amongst Blueberry Farms, Angelica Maria Abdallah Ruiz Dec 2022

Efficacy Of Antimicrobial Treatments In Vitro And On Fresh Produce Against Selected Foodborne Pathogens And Microbiome Diversity Amongst Blueberry Farms, Angelica Maria Abdallah Ruiz

Theses and Dissertations

This study focused on evaluating the antimicrobial activity of chlorine dioxide (ClO2) and different plant-based antimicrobials (carvacrol, thymol, and eugenol as bioactive compounds and muscadine extract- ME and blueberry extract- BBE as plant extracts) against selected foodborne pathogens under in vitro conditions and on produce (spinach and blueberries). In addition, bacterial microbiota associated with blueberries and blueberry farm environments from three different regions: Cundinamarca, Colombia; Mississippi, United States; and Guadalajara, Mexico, was determined. Under in vitro conditions, carvacrol and thymol were more effective (lower MICs and MBCs) than eugenol against Salmonella spp., Escherichia coli O157:H7 (MIC=MBC=0.2 mg/ml), and …


Survival, Regrowth And Morphotype Formation Of Salmonella Strains After Exposure To High Or Low Concentrations Of First Generation Qac In Water, Grace Umutesi Dec 2022

Survival, Regrowth And Morphotype Formation Of Salmonella Strains After Exposure To High Or Low Concentrations Of First Generation Qac In Water, Grace Umutesi

Theses and Dissertations

This study determines the differences in survival of eight Salmonella strains concentration of BAC in water, followed by regrowth in high and low nutrition conditions containing sublethal concentration of BAC. Our results show strain difference in survival, persistence of Salmonella in BAC at different concentrations. All eight strains of Salmonella were non-recoverable when exposed to 40 to 48 µg/ml BAC for 1h in water. When exposed to 24 µg/ml of BAC for 1 h in water, S. Typhimurium ATCC 14028 and S. Heidelberg ATCC 8326 cells were non-detectable from the initial 7 log CFU/ml. S. Blockley 7175, S. Virchow 7207, …


The Effects Of Glyphosate Salts And Volatility-Reducing Agents (Vra) On Dicamba Volatility, Nicole Glenn Dec 2022

The Effects Of Glyphosate Salts And Volatility-Reducing Agents (Vra) On Dicamba Volatility, Nicole Glenn

Theses and Dissertations

Dicamba is often tank mixed with glyphosate to increase herbicidal efficacy but may contribute to off-target movement (OTM). In recent years, volatilization has become problematic for dicamba-containing herbicides, resulting in increased regulatory requirements necessitating the use of volatility-reducing agents (VRA) for application. Research was conducted in 2021 and 2022 using low tunnels in a field environment and humidomes in a greenhouse environment to further assess how glyphosate salts and VRAs affect dicamba volatility. Our data indicate that the inclusion of glyphosate to dicamba can increase dicamba volatility, depending on the glyphosate salt used. The inclusion of the evaluated VRAs will …


Molecular Insights Into The Redox Of Atmospheric Mercury Through Laser Spectroscopy, Rongrong Wu Cohen Dec 2022

Molecular Insights Into The Redox Of Atmospheric Mercury Through Laser Spectroscopy, Rongrong Wu Cohen

Theses and Dissertations

The widespread pollution of mercury motivates research into its atmospheric chemistry and transport. Gaseous elemental mercury (Hg(0)) dominates mercury emission to the atmosphere, but the rate of its oxidation to mercury compound (Hg(II)) plays a significant role in controlling where and when mercury deposits to ecosystems. Atomic bromine is regarded as the main oxidant for Hg(0) oxidation, known to initiate the oxidation via a two-step process in the atmosphere – formation of BrHg (R1) and subsequent reactions of BrHg with abundant free radicals Y, i.e., NO2, HOO, etc. (R2), where the reaction of BrHg +Y could also lead to the …


Seasonal Trends And Sampling Time Of Day On Overall Microbial Population And Indicator Organisms In Catfish Parts And Catfish Processing Environment, Maria Gabriela Hidalgo-Sindoni Dec 2022

Seasonal Trends And Sampling Time Of Day On Overall Microbial Population And Indicator Organisms In Catfish Parts And Catfish Processing Environment, Maria Gabriela Hidalgo-Sindoni

Theses and Dissertations

Commercial production of catfish is the leading aquaculture industry in the United States. Production in Mississippi, Louisiana, Alabama, and Arkansas representing 96% of the total catfish sales in the USA. In 2017, the USDA-FSIS added testing of generic Escherichia coli and Enterococcus to the sampling of Siluriformes. The incidence of Escherichia coli in fish and seafood has been associated with possible fecal matter contamination. However, this indicator bacteria could also be a part of the natural microflora of catfish ponds where processing plants collect hybrid catfish. Aerobes, Psychrotrophs, Coliforms, Escherichia coli, and Enterobacteriaceae counts among environmental, liquid and fish …


Animal Husbandry In The 21st Century: Application Of Ecological Theory And Precision Technology To Inform Understanding Of Modern Grazing Systems, Ira Lloyd Parsons Dec 2022

Animal Husbandry In The 21st Century: Application Of Ecological Theory And Precision Technology To Inform Understanding Of Modern Grazing Systems, Ira Lloyd Parsons

Theses and Dissertations

Ruminant animals comprise the greatest proportion of herbivores around the world, provide essential ecosystem services and human consumable protein by consuming grass and human inedible dietary fiber. Herbivory pressure alters plant communities and species diversity, effectively making grazing animals ecosystem engineers in dynamic ecosystems. Development of advanced computer processing power coupled with biometric and ecosystem sensors may be employed in the internet of things framework to create an integrated information system designed to inform understanding of grazing system function and animal energy balance. Towards this end, I utilized Bos indicus / Bos taurus crossbred steers (n = 20) across two …


Understanding The Relationship Among Cool Temperatures, Growth, Metabolism, And Energy Use Of Ictalurus Spp., Abby Vaughn Dec 2022

Understanding The Relationship Among Cool Temperatures, Growth, Metabolism, And Energy Use Of Ictalurus Spp., Abby Vaughn

Theses and Dissertations

Although U.S. commercial catfish aquaculture ponds are in temperate regions and experience cool to cold temperatures during the winter, few studies have investigated the effects of low temperatures on catfish physiological processes. Therefore, growth, metabolism, swimming performance, and blood variables were compared between channel (Ictalurus punctatus), blue (I. furcatus), and hybrid (I. furcatus x I. punctatus) catfish at 10 and 20°C. Accelerometers were also used to evaluate relationships among acceleration, metabolism, and tail beat frequency (TBF) during swimming performance tests. Channel catfish experienced the greatest growth, yet growth was diminished across all fish types at 10°C. Metabolic processes, swimming performance, …


Seasonal Comparison On The Effectiveness Of Control Methods For Microstegium Vimineum In The North Carolina Piedmont, Casey Beam Dec 2022

Seasonal Comparison On The Effectiveness Of Control Methods For Microstegium Vimineum In The North Carolina Piedmont, Casey Beam

Theses and Dissertations

Microstegium vimineum, or Japanese stilt grass, is an invasive species that readily outcompetes native vegetation and is of poor forage quality for wildlife. This species is widespread throughout the southeastern United States, including North Carolina. Much of this region is privately owned and there is a gap in the literature providing succinct information about the best methods of treatment, timing of treatment, and effects of treatment on native herbaceous plants in this region. In two parts, this study seeks to address this gap by employing treatments that are easily accessible to landowners at different times during the growing season and …


Development Of Alternative Air Filtration Materials And Methods Of Analysis, Ivan Philip Beckman Dec 2022

Development Of Alternative Air Filtration Materials And Methods Of Analysis, Ivan Philip Beckman

Theses and Dissertations

Clean air is a global health concern. Each year more than seven million people across the globe perish from breathing poor quality air. Development of high efficiency particulate air (HEPA) filters demonstrate an effort to mitigate dangerous aerosol hazards at the point of production. The nuclear power industry installs HEPA filters as a final line of containment of hazardous particles. Advancement air filtration technology is paramount to achieving global clean air. An exploration of analytical, experimental, computational, and machine learning models is presented in this dissertation to advance the science of air filtration technology. This dissertation studies, develops, and analyzes …


Combined Effects Of Cyclosporine And Prednisone On T-Cell Cytokine Production In Healthy Dogs, Brittany Moore-Henderson Dec 2022

Combined Effects Of Cyclosporine And Prednisone On T-Cell Cytokine Production In Healthy Dogs, Brittany Moore-Henderson

Theses and Dissertations

Cyclosporine and prednisone are immunosuppressive drugs that are commonly used in combination for the treatment of immune-mediated diseases, and have been shown to individually cause significant suppression of IL-2. Currently, no studies have been performed to determine how a combination of the two drugs would impact suppression of IL-2, and if an additive or synergistic effect on cytokine production could be demonstrated, as in studies of other species. An additive effect of immunosuppression associated with this drug combination could allow clinicians to decrease dosages of drugs, thereby reducing drug costs and minimizing adverse drug side effects. In a cross-over study …


Analysis Of Process And Environmental Parameters Impacting Membrane Fouling, Methane Production, Soluble Microbial Products, Extracellular Polymeric Substances And Chemical Oxygen Demand Removal In Anaerobic Membrane Bioreactors Wastewater Treatment, James Mark-Ige Dec 2022

Analysis Of Process And Environmental Parameters Impacting Membrane Fouling, Methane Production, Soluble Microbial Products, Extracellular Polymeric Substances And Chemical Oxygen Demand Removal In Anaerobic Membrane Bioreactors Wastewater Treatment, James Mark-Ige

Theses and Dissertations

Aerobic (AeMBRs) and Anaerobic Membrane Bioreactors (AnMBRs) are an essential part of the advanced wastewater treatment options, which offer advantages in terms of higher effluent discharge and smaller footprints over the traditional wastewater treatment. This study evaluates the performance of (AnMBRs) by analyzing the cumulative effect of eleven physico-chemical parameters from the data obtained from the studies conducted from year 2000 onwards. Effect of various parameters such as Solid Retention Time (SRT), Hydraulic Retention Time (HRT), Mixed Liquor Suspended Solids (MLSS), influent Chemical Oxygen Demand (COD), Organic Loading Rate (OLR), influent COD, and temperature on the COD removal, methane production …


Unraveling The Anti-Inflammatory Mechanisms And Efficacy Of Cannabidiol On The Progression Of A Murine Model Of Multiple Sclerosis From The Innate To The Adaptive Immune System To Clinical Symptoms, Christa Marie Frodella Dec 2022

Unraveling The Anti-Inflammatory Mechanisms And Efficacy Of Cannabidiol On The Progression Of A Murine Model Of Multiple Sclerosis From The Innate To The Adaptive Immune System To Clinical Symptoms, Christa Marie Frodella

Theses and Dissertations

Cannabidiol (CBD), a non-psychotropic phytocannabinoid with structural similarity to Δ 9 -tetrahydrocannabinol (THC), is currently being investigated as a therapeutic for its immunosuppressive effects. One disease for which CBD is extensively researched is multiple sclerosis (MS), a demyelinating, autoimmune disorder, and its murine model counterpart, experimental autoimmune encephalomyelitis (EAE). The focus of this dissertation aimed to analyze the transcriptomic brain pathways in EAE and its comparison to MS in addition to CBD’s immunosuppressive mechanisms in the innate and adaptive immune systems. Evidence presented here showed that transcriptomic signaling pathways in the EAE brain of mice with clinical symptoms were similar …


Development Of A Crosslinked Osteochondral Xenograft And A Collagen Stabilizing Intra-Articular Injection To Remediate Cartilage Focal Lesions To Prevent Osteoarthritis, Mark Lewis Mosher Dec 2022

Development Of A Crosslinked Osteochondral Xenograft And A Collagen Stabilizing Intra-Articular Injection To Remediate Cartilage Focal Lesions To Prevent Osteoarthritis, Mark Lewis Mosher

Theses and Dissertations

Osteoarthritis is one of the most common causes of disability in adults in America. It is a progressive and degenerative disease where the articular cartilage is broken down and lost from the surfaces of bones causing chronic pain and swelling in the joints, and currently has no cure. The most commonly osteoarthritis starts from a focal lesion on the cartilage surface, which will expand on the surface and downwards through the thickness of the tissue. The current gold standard for correcting cartilage focal lesions is the osteochondral autograft/allograft transplantation (OAT), which replaces the defect with a fresh osteochondral graft. The …


Effects Of Microcystin-Lr On Channel Catfish (Ictalurus Punctatus) Susceptibility To Microbial Pathogens (Aeromonas Hydrophila And Edwardsiella Piscicida), Alison Marchant Dec 2022

Effects Of Microcystin-Lr On Channel Catfish (Ictalurus Punctatus) Susceptibility To Microbial Pathogens (Aeromonas Hydrophila And Edwardsiella Piscicida), Alison Marchant

Theses and Dissertations

Microcystin-LR is a hepatotoxin produced by cyanobacteria. Aeromonas hydrophila and Edwardsiella piscicida infections are leading causes of losses in market-sized channel catfish (Ictalurus punctatus). These older fish should have natural immunity in place and a predisposing factor is likely a prerequisite for these disease outbreaks. While microcystin-LR rarely causes mortality in warm-water aquaculture, we believe it may be a predisposing factor that leads to bacterial disease outbreaks during the summer months due to its ability to damage the liver. Our study investigated microcystin-LR’s effects on channel catfish susceptibility to these pathogens. We found that a sublethal dose of microcystin-LR induced …


Vegetation And Nutritional Changes Over 20 Years Of White-Tailed Deer Exclusion, Gabrielle Nicole Ripa Dec 2022

Vegetation And Nutritional Changes Over 20 Years Of White-Tailed Deer Exclusion, Gabrielle Nicole Ripa

Theses and Dissertations

Knowledge of the impacts of white-tailed deer (Odocoileus virginianus; hereafter deer) as dominant herbivores throughout the Southeastern United States of America is lacking. To address this, three paired experimental units of exclosures and controls were constructed in 2000 on three Wildlife Management Areas across Mississippi within the ecoregions of the Upper Coastal Plain, Lower Coastal Plain, and the Mississippi Alluvial Valley. Vegetation was sampled in the summers of 2000, 2005, and 2021 including vegetation structure, canopy coverage, basal area, and species composition. Additionally, in 2005 and 2021, biomass was sampled to determine potential impacts on nutritional carrying capacity. Among the …


Molecular And Phenotypic Characterization Of Escherichia Coli Isolated From Broiler Chicken Flocks In Mississippi, Priyanka Devkota Dec 2022

Molecular And Phenotypic Characterization Of Escherichia Coli Isolated From Broiler Chicken Flocks In Mississippi, Priyanka Devkota

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is the causative agent of colibacillosis. APEC causes significant economic losses to the poultry industry. In this study, 66 E. coli isolates were collected from broiler flocks across Mississippi and categorized as clinical and non-clinical isolates. Genotypic and phenotypic characterization of virulence factors and antimicrobial resistance profiles of these E. coli were examined. The data disclosed a higher prevalence of virulence genes in clinical isolates than in non-clinical isolates. High differences on the genotypic and phenotypic antimicrobial resistance among clinical and non-clinical isolates were observed. Whole genome sequences of avian E. coli elaborated a diverse …


Endotoxin As A Marker For Water Quality, Anas A. Sattar, Christian R. Good, Margaux Saletes, João Brandão, Simon K. Jackson Dec 2022

Endotoxin As A Marker For Water Quality, Anas A. Sattar, Christian R. Good, Margaux Saletes, João Brandão, Simon K. Jackson

School of Biomedical Sciences

Background: Water quality testing is vital to protect human health. Current testing relies mainly on culture-based detection of faecal indicator organisms such as Escherichia coli (E.coli). However, bacterial cultures are a slow process, taking 24–48 h and requiring specialised laboratories and trained personnel. Access to such laboratories is often sparse in developing countries and there are many fatalities deriving from poor water quality. Endotoxin is a molecular component of Gram-negative bacterial cell walls and can be used to detect their presence in drinking water. Method: The current study used a novel assay (BacterisK) to rapidly detect endotoxin in various water …