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Marine Heatwaves And Fish Reproduction: Endocrine Responses In The Eurythermal Sheepshead Minnow (Cyprinodon Variegatus), Isabel Villafuerte

Master's Theses

Marine heatwaves associated with climate change are increasing in frequency and severity, posing significant threats to fish populations in shallow habitats such as estuaries and salt marshes. Because temperature is a primary regulator of fish reproduction, understanding how heatwaves affect reproductive physiology is critical for anticipating the biological consequences of ongoing climate change for coastal fishes. Here we examined how simulated heatwave conditions affect the reproductive hypothalamic-pituitary-gonadal (HPG) endocrine axis in the estuarine sheepshead minnow (Cyprinodon variegatus), a eurythermal fish well suited to studying thermal stress responses in estuarine environments. Adult sheepshead minnows acclimated to a daily oscillating …

Effects Of Hot Water Dipping And Sub-Zero Saline Chilling On The Microbial Safety Of Broiler Carcasses And Recycled Chilling Water, Elen Zhu

Master's Theses

Broiler meat became the most widely consumed meat within the United States and across the world in 2019. The trend of increasing broiler consumption is expected to continue due to affordability, health benefits, and production efficiency. To meet the growing demand of broilers, a substantial number of birds need to be produced and processed while minimizing bacteria contamination, water consumption and wastewater generation.

In this study, the microbial safety (mesophilic aerobic bacteria, coliforms, and Escherichia coli) of broiler carcasses and post-chill water (red water) was assessed, using innovative processing techniques and red water recycling. A total of 144 broilers …

Independent And Combined Effects Of Early-Life Iron Deficiency And Antibiotic Exposure On Growth And Hematological Outcomes In A Piglet Model, Ginger M. Fitzpatrick

Master's Theses

Iron deficiency (ID) affects over 2 billion individuals globally. Children under 5 are at increased risk of ID due to rapid growth and are especially vulnerable to its negative consequences because of iron’s essential role in cognitive development and immune maturation. ID is the leading cause of iron deficiency anemia (IDA), with IDA affecting approximately 40% of children in this age group. Antibiotic (abx) exposure is also prevalent during early life and may disrupt growth and through gut dysbiosis, with increasing use posing additional risk in younger populations. Geographically, there is overlap in regions with high anemia prevalence and those …

Assessing Nitrogen Leaching Risk In Organic Vegetable Production, Megan Widle

Master's Theses

Nitrogen (N) leaching is the primary driver of groundwater contamination in agricultural regions. On California’s Central Coast, Agricultural Order 4.0 regulates this risk by constraining field-level N balances (N applied minus N removed). However, the assumption that unrecovered N is lost via leaching may not hold in organic and regenerative systems that promote soil organic matter accumulation. This study evaluated whether measured N leaching aligns with estimates derived from partial N budgets in organic systems, and whether management practices (intercrops, cover crops, and reduced tillage) can mitigate leaching risk. Four field trials were conducted to investigate N dynamics in organic …

Evaluating The Commercial Aquaculture Potential Of The Native Pacific Littleneck Clam (Leukoma Staminea) As A Climate Resilient Alternative To The Non-Native Manila Littleneck Clam (Ruditapes Philippinarum)., Skylar M. Wuelfing

Master's Theses

The California shellfish industry’s near-exclusive reliance on the non-native Manila littleneck clam (Ruditapes philippinarum) creates an economic vulnerability to climate-driven disturbances, which can cause mortality events that eradicate up to 80% of stocks. This singular reliance on an introduced species highlights a need for the evaluation of native alternatives like the Pacific littleneck clam (Leukoma staminea). Our goal was to assess the feasibility of using the native Pacific littleneck in commercial aquaculture by comparing their performance to the non-native Manila littlenecks across the following conditions: 1) a five-month field outplant trial at high and low intertidal …

Nlrp3 Inflammasome: A Link Between Systemic Infection And Alzheimer’S Disease, Tatiana Barichello, Felipe Dal-Pizzol

Faculty, Staff and Student Publications

No abstract provided.

Partial Insect-Based Meal Inclusion In The Diets Of Ross® 308 Broilers Upregulates Growth And Immune Related Genes, Victor K. Rotich, Isaac M. Osuga, Mathew G. Gicheha, Shaphan Y. Chia, Jandouwe Villinger, Anderson N. Maina, Jinhua Xiao, Dennis Beesigamukama, Chrysantus M. Tanga

All Peer-Reviewed Publications

This work investigated the effects of black soldier fly ( Hermetia illucens L.) larvae meal (BSFLM) on growth- and immune-related gene expression in Ross 308 broilers. Birds were fed diets containing soybean meal (SBM), fishmeal (FM), combinations with BSFLM, or BSFLM alone. Growth, organ weights, immune genes [interleukin-2 (IL-2), interleukin-6 (IL-6), tumor necrotic factor alpha (TNF-α), interferon-gamma (IFN-γ)] and growth-related genes [chicken growth hormone (cGH), insulin growth factor 1 (IGF-1)] expression were measured. Our results demonstrate that birds fed FM+BSFLM had significantly higher final liveweight, average daily weight gain (ADG), and low feed conversion ratio. Birds fed FM+BSFLM showed highest …

Climate-Driven Stochastic Modelling Of Crimean-Congo Haemorrhagic Fever Transmission In Uganda, P. G. Kpatchana, J. Aduda, K. M. Agboka

All Peer-Reviewed Publications

Crimean-Congo haemorrhagic fever (CCHF) is a climate-sensitive tick-borne zoonosis that remains a significant public health concern in Uganda, where temperature and vapour pressure deficit influence tick ecology and consequently disease transmission. This study aimed to develop and analyse a climate-driven stochastic model for CCHF transmission among ticks, livestock, and humans under environmental variability in Uganda. A compartmental transmission model was formulated and extended into a stochastic differential equation framework by incorporating multiplicative environmental noise. Climate-dependent tick recruitment, development, and mortality were parameterized using district-level temperature and vapour pressure deficit data to capture spatial heterogeneity in transmission risk. Theoretical analyses based …

Viruses Causing Panleukopenia In Domestic Cats: A Review Of Feline And Canine Parvoviruses, Simon Colby

University Honors Theses

Parvoviruses remain among the most important viral pathogens in domestic cats today. Despite this, there is much confusion around which parvoviruses can infect cats, and what extent of disease they can cause. One of the two parvoviruses infecting cats, canine parvovirus type-2 (CPV-2), likely evolved from the other parvovirus infecting cats, feline parvovirus (FPV). These viruses differ at only a few places in their genomes, and share the method of cell entry via the transferrin receptor. The disease caused by FPV has been well characterized in cats, but disease caused by CPV-2 is more obscure. Additionally, current testing methods for …

Shallow-Marine Crinoid Genera May Have Been More Resilient Across Permian Extinction Events In Terms Of Richness Than Deep-Marine Crinoid Genera, Amelia C. Kolstad

University Honors Theses

Throughout the Phanerozoic, one of the most successful phyla of marine invertebrates has been Echinodermata. Echinodermata was particularly successful throughout the Paleozoic, with class Crinoidea making up a majority of occurrences. The proportion of echinoderm occurrences that are crinoids declined massively at the end of the Permian and continued to decrease into modern day, never fully recovering. One of the factors thought to have been so important for crinoid success in the Paleozoic and their decreasing success throughout geologic time has been their propensity for success in shallow-marine environments, though crinoids also exist within deep-marine environments. This study seeks to …

Synergies Of Microecology And Macroecology Elicit Insights For Creation Care, David Warners, John T. Wertz

University Faculty Publications and Creative Works

This article reports on a collection of microecological and macroecological insights that emerged from extended conversations between Calvin University professors David Warners, a botanist concentrating in restoration ecology, and John Wertz, a micro-biologist specializing in microbial ecology. Classic descriptions of ecology identify biological interactions as happening at the ecosystem, community, or population level. And yet, ecological interactions are very much occurring at the microbial level as well. Furthermore, microbial-level interactions frequently influence the quality and character of macroecological relationships and vice versa. Allowing ecological principles to be applied across all life forms broadens our comprehension of interactions that are happening …

Part I: Drip Tape Irrigation For Cut Flowers, Alex Rodriguez, Melanie Stock, James Frisby, Burdette Barker

All Current Publications

Drip irrigation can be the most efficient method for delivering water and has the added benefit of keeping moisture off foliage and blooms of cut flowers. This fact sheet is the first in a series of irrigation fact sheets for cut flowers. It provides a step-by-step guide to the initial selection and installation of a surface drip tape irrigation system. Descriptions of and considerations for common components, setup, management, and repair are discussed. While this content may apply to other horticultural and garden plants, this fact sheet was developed for cut flower crops and growers. We recommend USU Extension resources …

Geographic Range And Body Size Influence Abundance Patterns In Reef Fishes, M. F. Maxwell, D. R. Barneche, R. Divieso, S. R. Floeter, O. J. Luiz, A. L. Luza, M. R. Pie, A. C. Siqueira, M. G. Bender

Research outputs 2022 to 2026

Aim: Understanding how body size and geographic range size influence species abundance is central to macroecology. Here, we characterized these relationships for reef fishes, the world's most diverse vertebrate group, across global and regional scales. Location: Global tropical and subtropical reefs. Time Period: Current. Major Taxa Studied: Reef-associated fishes. Methods: We compiled a comprehensive dataset on abundance, body size and geographic range size for 828 reef fish species. Abundance was measured as density (ind/m²) using transect-based observational data. To analyse global-scale patterns, we applied Bayesian quantile regressions and Bayesian phylogenetic regressions to account for phylogenetic relatedness. We also …

Sporadic Appetites: Unearthing The Fungal Diets Of Two Mycophagous Mammals Across An Australian Climate Gradient, Rebecca J. Quah, Saul J. Cowen, Robert A. Davis, Harriet R. Mills, Anna J.M. Hopkins

Research outputs 2022 to 2026

Translocating threatened ecosystem engineers may offer the dual benefit of contributing to species conservation and ecosystem restoration. Boodies (burrowing bettong; Bettongia lesueur) and woylies (brush-tailed bettong; Bettongia ogilbyi) are threatened mycophagous marsupials known for their crucial role in ecosystem health through fungal dispersal and bioturbation. As part of restoration efforts across Australia, these bettong species are frequently targeted for translocations, where a better understanding of their fungal dietary requirements is essential for ensuring their resource requirements are met and in predicting their ecological contributions to recipient ecosystems. Here, we used DNA metabarcoding to study the fungal diets of boodies and …

The Cultivation Of Public Perception: Cultivated Meat Narratives And Misinformation On Tiktok, Anna M. Balkus

Graduate Masters Theses

Cultivated meat is an emerging tissue engineering technology that has the potential to address major issues threatening food systems, including climate change, rapid population growth, and the spread of disease. Among technical challenges, public perception remains a significant barrier for the widespread adoption of cultivated meat. While social media has transformed communication globally, it has simultaneously contributed to corrupt online environments infected with misinformation—unintentional inaccuracies that differ from disinformation, which is spread with the intent to mislead. The way the public receives and digests information regarding new food technologies, like cultivated meat, will be shaped by their social media environment. …

Transcranial Ac Modulation Of Cerebellar Nuclear Activity In Awake Animals, Nuran Kavakli

Dissertations

Entrainment of cerebellar nuclear (CN) cells via cerebellar transcranial alternating current stimulation (ctACS) has been reported in animals under ketamine/xylazine anesthesia. Our main objective was to demonstrate modulation of CN activity in unanesthetized, freely moving animals using ctACS. Multi-channel carbon-fiber electrodes were implanted into the interpositus nucleus for recording multi-unit (MU) activity, and thin-film electrodes were implanted subcutaneously over the posterior cerebellum for stimulation. A frequency-domain-based metric was developed to quantify modulation from MU signals. The results demonstrated modulation in a wide range of frequencies (4 Hz-300 Hz) as in anesthetized animals. In contrast, the amplitude of the peak in …

Pickleweed In The Disappearing Marsh: Population Genetics & Metal Accumulation In Salicornia Depressa, Alice Kaisla

Graduate Doctoral Dissertations

Salicornia is a genus of succulent halophytes found in salt marshes around the world. Salicornia species have a remarkably high tolerance for heavy metal pollution and have been shown to accumulate high concentrations of heavy metals in their tissue under experimental conditions. As a result, they are both a useful system for studying evolution in polluted coastlines and a potential candidate for use in phytoremediation. My research focuses on Salicornia depressa, known as pickleweed, a species commonly found in marshes along the heavily urbanized and industrialized New England coast. I investigate genetic diversity and population structure in S. depressa populations …

Investigation Of Environmental Influences On Multiple Sclerosis: A Study For Egypt’S Health, Noha Ezzaldin Alziny Ali

Theses and Dissertations

Background: Multiple sclerosis (MS) is a complex, chronic neuroinflammatory disease influenced by both genetic and environmental factors. While global research has identified potential environmental influences, most evidence comes from Western populations, creating a significant knowledge gap for regions like Egypt, which has witnessed a dramatic rise in MS prevalence over recent decades. This study hypothesized that Egyptian MS patients exhibit a distinct biological signature in their blood, characterized by an imbalance in essential and toxic trace elements (the metallome) and alterations in stress-response biomarkers associated with neuroaxonal injury and cellular stress. Objective: This study aimed to comprehensively profile and compare …

Is Trimethylamine N-Oxide A Friend, Foe, Or Hormetic Agent In Patients With Parkinson’S Disease: A Focused Review Of One Microbial Metabolite, Abraham B. Alton

Student Works

This review synthesizes recent literature examining trimethylamine N-oxide (TMAO) synthesis and its potential role in Parkinson’s Disease (PD) pathology. An increase in TMAO plasma and CSF concentration is associated with PD progression and severity. TMAO biosynthesis is a two-step process. First, precursors including carnitine and choline are converted to trimethylamine (TMA) by gut microbes. Second, TMAO is oxidized to TMAO in the liver. Once absorbed into circulation TMAO crosses the blood brain barrier and may influence PD disease pathology by increasing neuroinflammation and astrocyte activation and damaging the cerebral lymphatic system. These mechanisms may contribute to the cognitive and motor …

Patents And Technology Evolution: Altering Innovations And Innovators Via Patent Influences, Richard Gruner

Journal of Intellectual Property Law

Technologies improve primarily through evolutionary change not rational optimization. New technologies emerge as attempts to solve practical problems, the technologies are tested in marketplaces to determine if they are superior in cost and function to alternatives, and those that fare well in the testing gain widespread adoption.  Widely adopted technologies, and their problems, form the basis for the next round of technology improvements and evolution.  Through these steps, evolutionary processes lacking rational direction can generate changing technologies matched to the desires and problems of present society.

As they operate to advance diverse technologies, evolutionary processes governing technology change are subject …

Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood

IGC Proceedings (1977-2023)

The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract in­filtrating …

Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney

IGC Proceedings (1977-2023)

Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …

Effects Of Water Stress On Herbage Quality, J R. Wilson

IGC Proceedings (1977-2023)

Uncertainty exists about whether drought is detrimental to the nutritive quality of herbage. This paper tries to resolve this uncertainty by examining the influence of soil moisture on some herbage-quality characteristics. Unpublished data from my own work and review of published literature are presented. Field plots of three tropical grasses, green panic (Panicum maximum var. trichoglume), buffelgrass (Cenchrus ciliaris), and speargrass (Heteropogon contortus), were subjected to perioqs of controlled drought, and herbage from these plots was compared with that from well-watered plots. Leaf and stem dry-matter ?igestibility of water-stressed herbage was either similar to or higher than that of unstressed …

Consumption Rates And Desert Grassland Herbivores, R D. Pieper

IGC Proceedings (1977-2023)

Studies were conducted on a desert grassland range in southern New Mexico for 3 years to determine relative consumption rates of the main herbivores utilizing these range areas. Consumption of some groups (cattle, pronghorn antelope, and rabbits) was determined from direct estimates of intake/individual, and density was determined from censusing procedures or known stock rates. Consumption by other groups (birds, rodents, and invertebrates) was determined from census information relating to age structure of the population and metabolic rate. Consumption by all herbivores averaged less than 5 % of the above-ground net primary productivity for the 3 years of the study. …

Performance Of A Subtropical Legume-Grass Pasture Under Different Grazing Management Systems, G E. Maraschin, S C. Mella, G S. Irulegui, J Riboldi

IGC Proceedings (1977-2023)

Agronomic evaluation of the dynamics of tropical legume-based pastures is relevant in assessing the response of their com­ponents within systems of grazing management. The response of tropical legume-grass mixtures to periods of rest and grazing pressure and the combinations that result in meaningful legume content in the mixture need to be known. A central composite design was used to study the performance of a Desmodium intortum (Mill.) U rb. and Paspalum gttenoarum Arech. pasture mixture to 14, 28, 42, 56, and 70daysofrestcombinedwith 2.0%, 3.5%, 5.0%, 6.5%, and 8.0% BW(i.e., kg dry matter (DM) on offer/day/100 kg body weight) as grazing …

Legume Establishment In Grass-Dominant Swards: Concept And History In Kentucky, T H. Taylor, W C. Templeton Jr

IGC Proceedings (1977-2023)

Grassland farming has been practiced for 2 centuries in central Kentucky and for shorter periods in other parts of the state. Savannas and tallgrass prairies were severely grazed by domestic animals and row-cropped by early settlers, destroying most of the indigenous plant species. By the early part of the 19th century, beef cattle were being produced on bluegrass (Poa pratensis L.) pastures and driven on foot to east-coast markets. During the first century of settlement, farmers learned to top-seed legumes into grass sods, and in the course of the last hundred years development of grassland technology for establishing legumes …

Seed And Seedling Dynamics Of Annual Medic Pastures In South Australia, E D. Carter

IGC Proceedings (1977-2023)

Annual species of Medicago (i.e., medics) are the key to successful cereal-pasture rotations in the integrated crop-livestock farming systems on the neutral to alkaline soils of southern Australia. However, many medic stands have deteriorated in recent years. This deterioration has prompted research on the effects of grazing sheep on the seed-seedling dynamics of annual medic­based pastures in the Mediterranean environment of South Australia, aiming to quantify the impact of medic seed reserves in or on the soil upon pasture establishment and productivty.

Animal-house experiments involving the feeding of purepod and pod-chaff diets to sheep and a field experiment have been …

Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons

IGC Proceedings (1977-2023)

To improve our understanding of grassland utilization under grazing, the physiology of a grazed sward was investigated. An enclosure method, infrared gas analysis, and radiocarbon were used to measure sward and single-leaf photosynthesis and assimilate utilization. Intake by sheep was also measured. Expanding and recently expanded leaves had high rates of net photosynthesis but leaf sheaths, whose projected area in a "hard" grazed sward equaled that of the lamina, had low efficiency and contributed little to canopy photosynthesis. But because high leaf efficiency did not compensate for the small leaf area, canopy photosynthesis decreased markedly as grazing intensity increased. Twice …

Grassland Development In The Southern Highlands Of Peru, E J. Stevens, P Villalta

IGC Proceedings (1977-2023)

This paper describes grassland development in Peru. Vegetation of the high alpine region of Peru, which occupies some 4 million ha, is dominated by native grasses normally producing less than 2,000 kg/ha dry matter annually. On land with ade­quate soil moisture, pastures based on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) were established successfully, but on drier sites alfalfa proved superior, producing over 12,000 kg/ha/yr in some trials. Alfalfa and clovers were also successfully introduced into improved native pastures by mechanical direct seeding and by hand sowing. With direct seeding, dry-matter production increased from about …

Pasture Evaluation In The Desertic Zone Of Venezuela For The Development Of Goat Production, A Gallardo, A Leone

IGC Proceedings (1977-2023)

The desertic zone of Venezuela is an area of approximately 4.1 million ha that represents 4.8 % of the total national territory, on which there are two million goats. Goats represent the main, if not the only, income source for 60,000 rural families. According to UNESCO (1973), the desertic zone of the country comprises two vegetation types, evergreen scrub and deciduous scrub. In each of these zones the plant species consumed by goats were collected and, for those plant parts consumed by the animals, chemically analyzed to determine nutritive value. Forage plants from other tropical countries were also in­troduced and …