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Evaluating The Effectiveness Of Individual Cleaning Steps Of A Cip Protocol In Membrane Biofilm Removal Under Dynamic Conditions, Diwaker Singh, Sanjeev Anand

Dairy Science and Food Science Faculty Publications: 2022 to Present

This study evaluated the effectiveness of individual clean-in-place (CIP) steps in removing biofilms from reverse osmosis (RO) membranes under dynamic flow conditions using the Centers for Disease Control (CDC) biofilm reactor. Biofilms were developed in the laboratory under continuous flow, using mixed-species bacterial isolates obtained from 10-month-old RO membrane biofilms from a commercial facility. Individual CIP chemicals, representative of those used in commercial protocols, were tested against 24 h-old biofilms. Additionally, a complete six-step sequential CIP process was conducted under dynamic conditions, consisting of treatments with alkali, surfactant, acid, enzyme, a secondary surfactant, and sanitizer. All experiments were performed in …

Two Essays On Index-Based Risk Management In U.S. Rangeland And Livestock Production, Wajdi Belgacem

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation investigates two distinct but complementary dimensions of risk management in United States rangeland agriculture. Essay 1 measures spatial variation in basis risk within the Pasture, Rangeland, and Forage (PRF) rainfall-index program for 176 Nebraska grid cells (1988–2023). By linking official NOAA rainfall indices with 30-m Rangeland Analysis Platform biomass estimates, we find rainfall–forage correlations that peak at 0.45 but display pronounced heterogeneity. The probability that neither insured interval triggers during an actual forage loss averages 12%, rising to nearly 30% in several Sandhills cells, whereas optimally pairing late-spring and summer intervals reduces complete misses below 10%. These results …

Polyphenols For The Mitigation Of Vascular Calcification; In Vitro And In Vivo Studies, Abdullah Altuhami

All Theses

Globally, cardiovascular diseases, in most cases associated with calcification, are the main cause of death. However, currently, the only effective cure is to undergo surgery to augment or receive a healthy donor heart, which could be very difficult due to the long waiting list and the associated risks. The possibility of body rejection of the foreign organs is attributed to immunoreaction or the risk of infection, since the donor must be on immunosuppressant drugs that lower the body's immunity and facilitate the body's acceptance of the new organ as one of its own. Taking that into consideration, using tissue-engineered vascular …

Crop, Soil Nutrient, And Soil Health Responses Within Integrated Crop And Livestock Systems, Alyssa K. Hall

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

We evaluated the influences of grazing livestock on crop production, soil nutrients, and soil health indicators of integrated crop livestock systems using three experiments during a seven-yr. period. Objectives were to (1) determine livestock grazing and cropping system effects on crop yield and soil properties across six yr. in corn-soybean (C-S) and wheat-corn-soybean (W-C-S) systems with and without periodic composted manure application, (2) explore seasonal variation in soil nutrient patterns over two yr., and (3) measure residual responses for corn grain yield plus soil health indicators in yr. seven following a six-yr. study. In experiment 1, neither livestock grazing ( …

Invited Review: Effects Of Management On Performance Of Stocker Cattle And Subsequent Feedlot Performance: A Review Within Applied Animal Science, M.A. Snider, M.S. Gadberry, J.D. Rivera

Animal Science Faculty Publications and Presentations

Purpose: The purpose of this review is to summarize relevant research from the journal Applied Animal Science (formerly known as The Professional Animal Scientist) between 1995 and 2024, that explores management practices and concepts as they relate to stocker calf performance and subsequent feedlot performance. A secondary objective of this review is to describe research trends and identify knowledge and research gaps within existing literature. Sources: Sources for this article included peer-reviewed scientific literature obtained from the journal Applied Animal Science, formerly known as The Professional Animal Scientist. Literature used in this review included original research, short communications, technical notes, …

Effect Of Amino Acid Derivatives And Polyphenol Supplementation On Skeletal Muscle Growth In-Vitro And In-Vivo, Gabriella C. Iheanacho

All Theses

Background

Satellite cells (SCs) are myogenic precursor cells that play a crucial role in muscle growth, and their activity can be influenced by nutrient supplementation. Muscle growth can also be stimulated using growth-promoting hormones; however, there are no approved growth hormones for use in sheep in the United States (Qaid & Abdoun, 2022). This limitation highlights a need to identify alternative compounds that would serve as nutrient supplements to enhance muscle growth and thereby improve meat production. Amino acid derivatives such as guanidinoacetic acid (GAA) and 5-hydroxytryptophan (5-HTP), along with the polyphenol quercetin, are naturally derived compounds that have shown …

In Vitro Assessment Of The Antihistomonal Activity Of Methyl Jasmonate And Jasmonic Acid, Mckayla B. Williams

Poultry Science Undergraduate Honors Theses

Histomonas meleagridis is a protozoan parasite and the causative agent of histomonosis in gallinaceous birds. There are currently no approved prevention or treatment options available for histomonosis control in the United States. Mortality in affected turkey flocks can exceed 80% which highlights the urgent need for research investigating novel strategies to mitigate histomonosis in the field. The objective of this study was to evaluate the in vitro antihistomonal and antibacterial effects of of methyl jasmonate (MeJA) and jasmonic acid (JA), two plant-derived compounds, in a xenic culture of H. meleagridis. Assays were conducted using cultured H. meleagridis (PHL strain) treated …

Effect Of Dietary Tryptophan Supplementation And Heat Stress On Pasture Broiler Welfare And Performance, Jaelen Matthew Cherry

Graduate Theses and Dissertations

Pasture-raised broiler chickens face temperature extremes that can threaten welfare. In the study, we evaluated whether a 0.26 % tryptophan-supplemented diet (T) improved heat stress (HS) resilience in Ross-708 broilers raised on pasture. At D14, birds began the T or remained on the control diet (C) and were moved outdoors. On D20 and 41, half of each group underwent six-hour HS; the remainder stayed under thermoneutral (TN) conditions. Weekly body weight, feed intake on D20 and D41 were recorded, and fear was measured using the Tonic Immobility (TI) test. Neither diet nor HS affected body weight. However, tryptophan supplementation resulted …

Site Fidelity, Seasonality, Movement, And Fish Associates Of Sand Tigers Carcharias Taurus In North Carolina, Ara L. Mcclanahan

Electronic Theses and Dissertations

Sand tigers Carcharias taurus are mackerel sharks with a disjunct global distribution in tropical and temperate seas. In the northwest Atlantic, sand tigers migrate along the coast of the eastern United States from the Gulf of Maine to Florida and occupy structurally complex benthic habitats. The long-term, underwater camera installation, SharkCam, at Frying Pan Tower, off Cape Fear, North Carolina, USA, sits atop an expanse of hard bottom reef frequented by sand tigers. The citizen-science platform Spot A Shark USA (SAS USA) uses images of sand tigers to identify and track individuals. This study utilized image encounters from SAS USA …

A Multi-Isotope Investigation Of Mammoth Diet, Habitat, And Movement Patterns In The Central Great Plains, U.S.A., Jacob Mccloskey

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

During the Last Glacial Maximum (LGM), the Great Plains in Nebraska consisted of wooded parklands and grasslands, whereas spruce (Picea) forests, parklands, and steppe grasslands dominated east of the Missouri River. I analyzed bulk carbon (δ¹³C), oxygen (δ¹⁸O), and strontium (⁸⁷Sr/⁸⁶Sr) isotopes from tooth enamel in isolated mammoth (Mammuthus) molars to compare diet and movement patterns in two late Pleistocene assemblages: one in Nebraska (n = 24), and one in western Iowa and Missouri (n = 17). Furthermore, I identified a morphometric subset of molars as …

Evaluation Of Performance Characteristics And Groundwater Contamination Risks Associated With On-Farm Swine Carcass Disposal Via Composting And Shallow Burial With Carbon, Gustavo Castro Garcia

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation evaluates the performance of three on-farm swine carcass disposal methods: whole carcass composting (WCC), ground carcass composting (GCC), and shallow burial with carbon (SBC), focusing on biosecurity factors and groundwater contamination risks. Foreign animal diseases (FADs), such as African swine fever and classical swine fever, pose severe economic and animal well-being risks if introduced to the United States. With confirmation of an FAD, swine movement will be halted, creating an urgent need for practical, biosecure, and environmentally responsible on-farm disposal strategies for swine carcasses. Nebraska, as a leading swine-producing state, exemplifies the vulnerability of high-density livestock regions to …

Trophic Roles And Climate-Driven Vulnerability For Benthic Invertebrates At Artificial Reefs In The Northern Gulf Of Mexico, Amanda Kirkland

LSU New Orleans Theses and Dissertations

Artificial reefs are deployed to enhance marine habitats and fisheries, yet their role in supporting secondary production and their vulnerability to climate stressors remain understudied. This dissertation investigates the trophic ecology and climate sensitivity of benthic invertebrates at artificial reefs in the northern Gulf of Mexico. Chapter 1 assessed reef food webs using stable isotopes from fishes, invertebrates, and primary producers across six reefs and two seasons. Mixing models showed that most fishes rely on benthic reef carbon, while suspension feeders consume plankton and sediment microphytobenthos. Isotopic niche analysis revealed functional diversity and seasonal shifts in δ¹³C and δ³⁴S, though …

Coyote (Canis Latrans) And Non-Target Wildlife Responses To Livestock Guardian Dogs At Sheep Grazing Sites On The California Central Coast, Tricia T. Nguyen

Master's Theses

Livestock depredation is one of the oldest and most widespread forms of human-wildlife conflict. The coyote (Canis latrans), a midsized canid, represents a significant proportion of domestic sheep depredations in the United States, costing livestock producers an estimated 24.6 million dollars annually. Management strategies for coyote-sheep depredation vary widely in their effectiveness and in their level of public support. Identifying appropriate strategies for farms, ranches, and other sheep grazing sites remains a pressing need due to the potentially negative consequences for surrounding ecosystems and socioeconomic outcomes for sheep producers. The livestock guardian dog (LGD) is a nonlethal control …

Microbial Guardians Of The Savannah: Unraveling The Gut Microbiome For African Carnivore Conservation, Laura E. Peirson

All NMU Master's Theses

Non-invasive fecal sampling is essential for wildlife gut microbiome (GMB) research, yet field conditions often limit preservation options. I compared gut bacterial communities in paired fecal samples preserved in stabilization tubes and air-dried in paper bags collected from anesthetized African lions (Panthera leo) and spotted hyenas (Crocuta crocuta) in Etosha National Park, Namibia. Additional opportunistic samples from carnivore kill sites were also analyzed. No significant differences in alpha or beta diversity were detected between preserved and dried samples, although bacterial beta diversity differed between preserved and opportunistic samples (PERMANOVA). Core bacterial communities remained consistent across sample …

Analysis Of The Scleroderma / Systemic Sclerosis Etiopathology Using The University Of California At Davis (Ucd)-Ssc Chicken Line, Angeline E. Rodriguez

Graduate Theses and Dissertations

Scleroderma/Systemic Sclerosis (SSc) is a multifaceted autoimmune disorder affecting approximately 300,000 people in the United States. Main features include vasculitis, immune dysfunction (innate and adaptive), autoantibody production, perivascular leukocyte infiltration, and extensive tissue fibrosis. The University of California, Davis (UCD) SSc chicken line was shown to exhibit all clinical and biological manifestations of human SSc. One early and distinctive clinical sign in both humans and UCD-SSc chickens is Raynaud’s phenomenon (RP), characterized by decreased blood flow in extremities and skin lesions. RP-like lesions develop in combs of UCD-SSc chickens within one- to two-weeks post-hatch, progressing from erythema and edema to …

Advancing Fishery Dependent And Independent Habitat Assessments Using Automated Image Analysis: A Fisheries Management Agency Case Study, Scott Evans, Bronson Philippa, Carlo Mattone, Nick Konzewitsch, Renae Hovey, Marcus Sheaves, Gary A. Kendrick, Lynda M. Bellchambers

Fisheries Research Articles

Advances in artificial intelligence and machine learning have revolutionised data analysis, including in the field of marine and fisheries sciences. However, many fisheries agencies manage sensitive or proprietary data that cannot be shared externally, which can limit the adoption of externally hosted artificial intelligence platforms. In this study, we develop and evaluate two residual network-based automatic image annotation models to process fishery specific habitat data to support ecosystem-based fisheries management in the Exmouth Gulf Prawn Managed Fishery in Western Australia. Using an extensive dataset of 13,128 manually annotated benthic habitat images, we train a grid-based annotation model and an image-level …

Arginine Vasotocin And Corticosterone In Nesting And Non-Nesting Loggerhead Sea Turtles In X’Cacel-X’Cacelito Sanctuary, Krista Blair Reed

Theses and Dissertations

Sea turtles exhibit distinct behaviors before and after egg laying, however, not all individuals successfully oviposit. Some females display disruptions in their typical nesting behavior, returning to the water without laying eggs, which is referred to as a non-nesting emergence (NNE). NNEs can be due to external disturbances on the beach, but why they occur is often unclear. Arginine vasotocin (AVT) is a neuropeptide involved in various physiological processes, including stimulating smooth muscle contraction of the oviduct to facilitate egg deposition in nesting sea turtles. On the other hand, corticosterone is the primary stress hormone in sea turtles and is …

Gut Passage Time In Small Mammals: Influences Of Small Mammal Traits, Digesta Phase, And Particle Morphology, Noah G. Hale

Electronic Theses and Dissertations

Dispersal is crucial in maintaining healthy ecosystems, but little is known about mechanisms influencing fungal spore dispersal by animals. We aimed to develop a more mechanistic understanding of the influence of fungal spore traits and small mammal traits on gut retention time. We fed three species of small mammals (shrew, mouse, vole), which differ in gut morphologies, digestive strategies, and activity a combination of markers including: liquid digesta phase (CrEDTA), small particle (fungal spores with diverse morphologies), and large particles (glitter and beads, representing plant cells and seeds, respectively). We found that hindgut fermenters selectively retained the liquid markers, spores …

Use Of The Protein Misfolding Cyclic Amplification For Food Safety And Drug Discovery, Maria R. Benavente Garcia-Huidobro

Dissertations and Theses (Open Access)

Prion diseases are fatal neurodegenerative disorders caused by the misfolding of the normal prion protein (PrP^C) into its infectious form (PrP^Sc). While the zoonotic potential of chronic wasting disease (CWD) remains uncertain, the presence of prions in food products raises public health concerns. Additionally, therapeutic strategies for prion diseases remain limited. This thesis presents a methodological exploration of the Protein Misfolding Cyclic Amplification (PMCA) technique to address these challenges in two key areas: (1) detecting CWD prions in processed meats subjected to common cooking procedures, and (2) identifying potential anti-prion compounds through a high-throughput PMCA adaptation. …

Improved Rumen Microbiome Interpretation Via Empirical Filtration Derived From Known Mock Microbiomes, Wesley A. Tom

School of Biological Sciences: Dissertations, Theses, and Student Research

The rumen microbiome plays a critical role in ruminant health and performance. As a consequence, many studies investigate microbial community composition using 16S rDNA based sequencing. As such, data quality and data filtering are critical to accurately identify microbial community composition. In this study we use mock communities to empirically select data filtering parameters to reduce artifact populations and compared the effect of filtering using different bioinformatic pipelines using rumen bacterial community data. The filtering parameters identified provides consistent estimates of rumen microbial diversity, regardless of bioinformatic pipeline utilized and provides a more accurate view of microbiome structure and composition. …

Insights Gained From Applying Molecular Techniques To Gray Triggerfish (Balistes Capriscus Gmelin, 1789) In The Mexican Caribbean, The Southern And Northwestern Gulf Of Mexico, Geaceli G. Orive

Theses and Dissertations

This study focuses on Balistes capriscus (Gray Triggerfish), a reef-associated species dependent on hard-bottom habitats in the Gulf of Mexico (GOM). Using mitochondrial DNA barcoding and phylogenetic analyses, genetic structure across four sites was assessed: Rio Grande Valley (RGV), Veracruz, Chinchorro Bank, and Xahuayxol. Samples from RGV and Veracruz exhibited limited haplotype diversity, minimal nucleotide divergence, and weak genetic differentiation-patterns consistent with recent population expansion and ongoing connectivity within the GOM. While the study centered on B. capriscus, all individuals from Chinchorro and Xahuayxol unexpectedly grouped with Canthidermis maculata (Spotted Oceanic Triggerfish), suggesting misidentification, cryptic diversity, or taxonomic uncertainty in …

Associations Of Variation In Mtdna With Feed Efficiency In Beef Cattle And The Evaluation Of Transcriptomic Changes In Fetal Kidney Due To Hydrallantois, Lauren Elizabeth Seier

Department of Animal Science: Dissertations, Theses, and Student Research

Project 1 focused on the central role that mitochondria play in ATP production, highlighting that variation within the mtDNA may influence feed efficiency. Variation in the mitochondrial genome was uncovered, and associations with feed efficiency in beef cattle were identified. Growth and feed intake phenotypes, as well as low-pass sequencing, were collected on beef steers across two populations. Protein coding variants were identified and used to classify animals into mitochondrial haplotypes. A linear mixed model was employed, which detected a significant association between mitochondrial haplotype and DMI. A significant haplotype with a variant in Complex I was associated with reduced …

The Effect Of Diet Formulations Containing Different Protein Sources On Energy And Nitrogen Utilization In Lactating Jersey Cows, Kortney Ann Harpestad

Department of Animal Science: Dissertations, Theses, and Student Research

It is well understood that lactating dairy cows require metabolizable protein (MP) for milk yield and milk protein synthesis. Diets with conventional feed sources like corn and soybean meal (SBM) may not sufficiently meet all MP and amino acid (AA) requirements so supplementation with more rumen undegradable protein (RUP) rich feeds or rumen-protected AA can be fed to support animal performance. The growth trajectory of biofuels has resulted in dramatic increases in the production of feeds like heat treated soybean meal (HTSBM). While the chemical composition of this product is understood, there is a need to better understand how HTSBM …

Drift Dynamics Of Early Life-Stage Invasive Carps, Saurav Karki

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Asian carp species pose significant ecological threats to North American freshwater systems due to their invasive nature and prolific reproduction. Their semi buoyant eggs develop while drifting downstream with the river current. Understanding early life-stage transport is therefore critical for predicting recruitment potential and guiding management efforts. Existing fluvial egg drift models, including those relying on 1-D hydraulics and fully 3-D CFD-based models, are either inadequate for complex braided rivers or too computationally demanding for large-scale application. The Platte River in Nebraska, characterized by wide, shallow, multi-threaded channels, is dominated by two-dimensional flow conditions, making a depth-averaged 2-D modeling approach …

Effect Of Marination And Storage Time On The Properties And Meat Quality Of Broiler Breast, Mayra Mabel Herrera Rivera

Graduate Theses and Dissertations

Abstract The poultry industry has implemented numerous methods, as marination and aging, to improve meat quality and satisfy consumer demands. Three experiments were developed to assess the effects of vacuum tumble marination and aging on the proteins of chicken breast. These experiments utilized 0.75 % sodium chloride, 0.45 % phosphate, and water in a marinade. In experiment one, 270 fillets were allocated into six treatment groups, each comprising 45 fillets. Six days of storage time were used, marinating and storing the fillets in each group at a temperature of 4°C. Following each day of storage period, the fillets underwent a …

The Influence Of Retail Display Conditions On Ground Beef Quality And Palatability, Sarah Lynn Shoup

Graduate Theses and Dissertations

The objectives of these studies were to evaluate the impact of retail display case type and muscle type on meat quality attributes, including color, lipid oxidation, texture, and volatile compound profiles, as well as to assess economic implications based on retail color degradation. Case type effects were further evaluated by considering environmental factors such as temperature, air velocity, and relative humidity and their influence on the shelf life of beef patties. An economic analysis was also conducted to estimate the value of patties based on a* (redness) scores at different points during retail display. In Study 1, differences in L* …

Freezing And Shipping Optimization To Increase Quality And Profitability Of Meat E-Commerce, Paul Olaoluwaniyi Dahunsi

Graduate Theses and Dissertations

Freezing remains one of the most reliable methods for preserving meat quality and extending shelf life. However, quality deterioration can still occur due to structural and biochemical changes activated during freezing, thawing, and distribution. Since the COVID-19 pandemic, consumers’ preference for bulk purchasing and online meat shopping has increased, raising questions about the best strategies to balance both quality maintenance and profitability. This thesis aimed to evaluate two key stages where frozen beef is most vulnerable to quality degradation: consumer-level freezing and post-purchase shipping. The objectives were (1) to determine the effects of product size and subsequent consumer freezing practices …

Hepatic Lipid Metabolism Of High And Low Water-Efficient Broiler Lines Under Heat Stress, Maria Fernandez Cuadrado

Graduate Theses and Dissertations

Heat stress (HS) is one of the most critical environmental challenges negatively impacting global poultry production, significantly compromising broiler performance, welfare, and economic viability. Specifically, heat stress profoundly disrupts physiological and metabolic processes, including hepatic lipid metabolism. Two broiler lines were divergently selected for high (HWE) or low (LWE) water efficiency. Heat-stressed HWE birds showed reduced fat content compared to their LWE counterparts, and HS reduced abdominal fat content in both lines. The purpose of this study was to determine the difference in underlying molecular mechanisms involved in this divergent fat content between the lines. Day-old chicks were placed in …

A Multicomponent Microneedle Patch For The Delivery Of Meloxicam For Veterinary Applications, Katherine Alejandra Miranda Munoz

Graduate Theses and Dissertations

Veterinary medicine requires innovative drug delivery strategies to enhance therapeutic efficacy while minimizing stress and handling. This dissertation explores the development and application of biodegradable microneedle patches for the transdermal delivery of meloxicam in livestock, offering a minimally invasive alternative to traditional administration methods. The research investigates the fabrication and characterization of microneedles using polyvinyl alcohol, collagen, and chitosan blends, demonstrating their mechanical strength, biocompatibility, and ability to facilitate sustained drug release. In vitro and in vivo evaluations confirm effective skin penetration, dissolution, and localized drug delivery. Pharmacokinetic studies highlight anatomical site-dependent variations in drug absorption, emphasizing the need for …

Impact Of Lighting Wavelength On Broiler Behavior, Health, And Performance, Angela Perretti

Graduate Theses and Dissertations

Lighting influences broiler production, health, and behavior. Due to their advanced visual system, avian species perceive a wide spectrum of light. The objective of this study was to investigate the effects of white (W, 350 to 780 nm) blue (B, 450 nm), and green (G, 560 nm) light on broiler production, processing performance, activity, fear, stress, blood cell profiles, tibiotarsi (tibia) morphology, and depth perception. Day-of-hatch by-product chicks from a Cobb 500 female line (N=600) were randomly assigned to 12 pens (N=4 treatment replicates). Body weight and feed consumption were recorded on day (D) 0, 14, 28, and 41, and …