Animal Sciences Commons^™

Comparison Of Sampling Methods For Estimation Of Aquatic Insect Diversity And Abundance Across Seasonal Gradients In A Southern U.S. River System, Albert Henry Gasperecz

LSU Master's Theses

Determination of benthic macroinvertebrate assemblage composition plays a vital role in assessment and management of lotic systems throughout the U.S. However, the validity of biomonitoring programs depends on accurate and precise measures of macroinvertebrate abundance, which in turn are dependent on sampling gears and protocols. The goal of this project was to assess how gear selection influences estimates of aquatic insect abundance and diversity, and how this selection can affect biological monitoring practices. I used 4 different gears in 3 southern Mississippi streams to aquatically and terrestrially collect aquatic insects seasonally throughout 2024. I identified and recorded all genera present …

Measuring The Rise And Fall Of Plasma 25-Hydroxyvitamin D Concentrations In Blue-Tongued Skinks (Tiliqua Scincoides) Following Ultraviolet B Exposure And Withdrawal, Ashleigh Godke, Haerin Rhim, M. Graciela Aguilar, Keishla Marrero-Acosta, Mark Mitchell

Distinguished Undergraduate Researcher Program

Species-specific husbandry guidelines remain limited for blue-tongued skinks (Tiliqua scincoides), especially in relation to ultraviolet B (UVB) lighting and vitamin D requirements. This study aimed to determine whether UVB exposure is necessary for these skinks and how long 25-hydroxyvitamin D (25-OHD) concentrations persist after UVB withdrawal. Eleven adult skinks who had been fed with wet cat food were exposed to 12 or 2 h of UVB per day for four weeks. Plasma 25-OHD concentrations were very low at the baseline, and significantly increased post-UVB in both groups (p < 0.01), with the 12-hour group increasing from baseline concentrations of 18.5 [12.8–20.5] nmol/L to 820 [730–1251.3] nmol/L and the 2-hour group increasing from baseline concentrations of 22 [15.5–22] nmol/L to 635 [401–892.5] nmol/L. Following the discontinuation of UVB exposure, 25-OHD gradually declined and was not significantly different from baseline concentrations at 7 and 4 months for the 12-hour and 2-hour groups, respectively. Dietary vitamin D3 (2.5 IU/g as dry matter basis), provided through wet cat food alone, appeared insufficient to support sustained plasma 25-OHD concentrations. These findings strongly suggest that blue-tongued skinks rely on UVB exposure to increase their 25-OHD concentrations. Moreover, the shorter 2-hour exposure provided a significant rise in 25-OHD concentrations and remained above baseline for 4 months, suggesting the shorter exposure can benefit these animals, while potentially reducing secondary risks associated with UVB exposure.

Effects Of Cryoprotective And Mitochondrial Stabilizing Agents On Vitrified Bovine Oocytes, Allison Hoang

LSU Master's Theses

Oocyte vitrification success is highly dependent on cryoprotectant agent (CPA) choice as well as possible additives that could help preserve mitochondrial membrane potential (mMP), reactive oxygen species (ROS) production, and calcium homeostasis within the cell. It is a delicate balance between levels needed for proper oocyte function and activation and levels needed to induce apoptotic pathways. The results of oocyte cryopreservation determine the eventual oocyte viability and subsequent fertilization and embryo development.

In this study potential permeating cryoprotectant combinations were explored such as ethylene glycol (EG) and propylene glycol (PG) or EG in combination with dimethyl sulfoxide (DMSO). Also, the …

Maternal Hyperleptinemia Alters Placental Transcriptome And Progesterone Regulation Without Affecting Early Equine Fetal Growth, Lucinda L. Thorburn

LSU Master's Theses

While consequences of equine obesity are well defined, the extent to which persistent hyperleptinemia and accompanying leptin (Lep) resistance affect the fetal-maternal environment warrants further exploration. This study compared endocrine, fetal, placental, and uterine parameters during early pregnancy (through day 70) in mares with elevated leptin versus normal leptin (NL) concentrations. Fourteen mares were classified as either NL (n = 6; Lep 0.9 ± 0.3 ng/mL), moderate leptin (ML; n = 4; Lep 3.0 ± 0.3 ng/mL), or high leptin (HL; n = 4; Lep 5.8 ± 0.7 ng/mL) based on annual plasma leptin. Mares were artificially inseminated and induced …

Stream Fish Assemblage Dynamics And Barriers To Aquatic Connectivity In The Ichawaynochaway Creek Watershed, Georgia, Usa, Jake R. Duhé

LSU Master's Theses

Stream fishes in the southeastern United States are adapted to hydrological disturbances such as droughts. However, this region is projected to experience increasingly frequent and severe disturbances that will elevate water demands given increasing agricultural and urban development. Further, road-stream crossings (RSCs) are abundant features in these streams that can exacerbate drought-mediated stream fragmentation and impede movements by many aquatic organisms, including fishes, when poorly constructed. These compounding effects may adversely affect the diversity and abundances of resident stream fishes, but their interactions remain poorly understood, warranting rigorous testing of how droughts and RSCs influence stream fish dynamics. I assessed …

The Design, Construction, And Testing Of Mrna Vaccine Against Equine Herpes Virus, Bhawana Devkota

LSU Master's Theses

Equine Herpesvirus-1 (EHV 1) is a worldwide significant pathogen that causes respiratory illness, abortion, and neurological disorders in equine. Current vaccines, including live attenuated, inactivated, and subunit platforms, do not prevent viral latency, mucosal shedding, or cross-strain immunity, requiring alternative approaches. To address these gaps, this project explores the design, synthesis, and in vitro testing of an mRNA vaccine targeting immunogenic EHV 1 glycoprotein (gB, gC, gD, gG, and gM). Epitopes were computationally predicted using the Immune Epitope Database (IEDB), codon-optimized for Bos taurus, and cloned into pUCIDT vectors using SP6/T7 promoters. In vitro transcription (IVT) used nucleotide modifications …

The Eastern Oyster Behavioral Response To Low Salinity And Hypoxia In Controlled And Natural Settings, Siyah Yongue

LSU Master's Theses

Oyster aquaculture is expanding in the northern Gulf of Mexico, but climate change may challenge the sustainability of this industry. Projected increases in the frequency and intensity of low salinity and low dissolved oxygen (DO) periods could impact the behavior, metabolism, growth, and survival of oysters. Characterizing how oyster behavior links to environmental stressors could help better identify thresholds in their tolerance and inform predictive tools for aquaculture professionals. In this research, the effect of separate and concomitant exposures to low salinity and DO on the behavioral response of oysters was examined in the lab. The impact of other environmental …

Analyzing The Catfish And Trout Competitiveness Trends And Potential Trade Within The Us And Global Aquaculture Industry: A Gravity Model Approach, Diana Marisol Amaya Discua

LSU Master's Theses

The United States is one of the major seafood product importers in the world. Despite the increases in global seafood and aquaculture consumption over the past decades, there is limited information on the trade dynamics of this sector. To address this gap, this study uses an augmented gravity model to evaluate the factors that have influenced catfish and trout imports into the United States. The analysis was conducted using the Poisson Pseudo Maximum Likelihood (PPML) estimator to address issues of heteroskedasticity, autocorrelation, and zero trade flows. The results highlight the importance of Gross Domestic Product (GDP) and exchange rates in …

Improving Bovine Intracytoplasmic Sperm Injection, Lauren Gatenby

LSU Doctoral Dissertations

Despite large efforts, there has been minimal improvements in bovine intracytoplasmic sperm injection (ICSI) in the last few decades. In this study, we investigate methods to improve embryo development rates with ICSI in cattle through addressing sperm and oocyte factors and modifying injection methods. Inducing the acrosome reaction in bull sperm prior to injection with progesterone increased cleavage (46.2% vs 16.2%) and blastocyst (21% vs 3.8%) rates compared to controls, respectively. Supplementing glutathione during in vitro maturation of the oocyte did reduce free reactive oxygen species (ROS) in the oocyte, but did not improve embryo development rates with ICSI or …

A Comparison Of Diploid And Triploid Eastern Oysters For Aquaculture Production Under Extreme Temperatures And Salinities, Joshua H. Kim

LSU Master's Theses

Off-bottom aquaculture of Eastern oysters (Crassostrea virginica) is a nascent industry that is increasingly supported by the use of triploid oysters, which grow faster than diploids. Despite their growth advantage, elevated triploid mortality compared to diploids under high temperature, low salinity, or a combination of these conditions challenge consistent triploid production. Identifying the environmental thresholds at which differential triploid mortality occurs and predicting its economic impact are important to informing decision-making in oyster aquaculture. The goal of this thesis was to compare the biological and economic performance of diploid and triploid oysters under high temperature and low salinity conditions. …

The Design, Construction, And Testing Of Nucleic Acid Vaccines Against Salmonella Enterica Subspecies Enterica Serovar Javiana, Alexis A. Nguyen

LSU Master's Theses

Salmonella spp. is a Gram-negative bacterium that has the ability to replicate within a variety of hosts, or within the environment, including water, soil, and vegetation. These characteristics, coupled with the zoonotic nature of non-typhoidal Salmonella, pose a significant public health concern. Salmonella is the leading cause of foodborne illnesses worldwide, and in the United States alone, the economic impact due to non-typhoidal Salmonella illnesses in 2013 was estimated to be $3.7 billion, the majority of which were due to mortalities. In a time of rising antibiotic resistance, antibiotics are no longer considered the most effective treatment for …

The Effect Of Season On Neuroendocrine Interactions In The Mare, Victoria N. Bailey

LSU Doctoral Dissertations

Reproductive seasonality in the mare involves various neuroendocrine modulations, and a series of experiments were conducted to investigate the anatomical and physiological roles of some of these seasonal modulators. The first experiment incorporated kisspeptin-10 (Kp10) into a treatment with estradiol benzoate (EB) and sulpiride, aiming to induce early cyclicity in seasonally anovulatory mares. Incorporation of Kp10 resulted in more mares ovulating earlier compared to mares receiving EB-sulpiride. Although plasma prolactin increased in both groups, concentrations were notably higher in Kp10-treated mares. Therefore, the subsequent experiment explored the anatomical interaction of kisspeptin and prolactin, aiming to determine whether kisspeptin may regulate …

A Novel Goat Model To Characterize Male Fertility Following Paternal Cannabidiol Exposure, Ashlyn N. Brewer

LSU Master's Theses

Despite the increasing use of cannabidiol, both for medical and social purposes, the effect of cannabidiol on male fertility is poorly understood. Previous studies have been carried out in rodent models, but a large animal model does not exist at this time. This experiment proposes chronic cannabidiol (CBD) exposure using a goat model to understand the impact CBD has on male reproductive performance. The purpose of this project is to determine if daily exposure to CBD in male goats would impact reproductive parameters such as sperm quality and testosterone levels.

Two studies were conducted to determine the effects of CBD …

The Use Of Duddingtonia Flagrans Aged In Mineral For Gastrointestinal Parasitic Nematode Control In Small Ruminants, Elisa M. Preston

LSU Master's Theses

Gastrointestinal nematodes (GIN) are a major constraint to small ruminant health and production throughout the world. Haemonchus contortus commonly known as the “barber pole worm” is a major concern for producers and veterinarians because of the severe anemia, and other clinical symptoms these worms cause. For decades, anthelmintics have been used to control the GIN burden small ruminants face. Katahdin (n=36) and Hampshire sheep (n=12) were used in a randomized block design experiment over a 30-day period. The objective of this study was to evaluate the effectiveness of Duddingtonia flagrans spores, the active ingredient in a commercial product, Bioworma® (International …

Parental Environnement Influences Offspring Gene Expression In The Olympia Oyster, Ostrea Lurida., Mark S. Yeats

LSU Master's Theses

The Olympia Oyster is the only native oyster species on the Pacific coast of North America. Seasonality in water temperatures across this threatened species’ broad and fragmented range has been linked to its development, reproductive timing, reproductive activity, growth, and survival rates. Recent evidence suggests parental environments can have carry-over effects on larval growth and respiration rates in response to temperature. In this study, we utilized transcriptomic methods to identify the underlying mechanisms of this cross-generation plasticity. Sequence libraries of adult ctenidia tissue and pooled larval replicates were extracted and spawned from hatchery raised oysters of the same parentage immediately …

An Intersection Of Science & Art: Vitrification Approaches And Open-Fabricated Tools For The Biomedical Model Sea Hare, Aplysia Californica, Allyssa M. Oune

LSU Master's Theses

The California sea hare (Aplysia californica) is an important biomedical model for molecular neurobiology, electrophysiology, learning, and memory due to their well-mapped and large neurons and well-characterized learning capabilities. The National Resource for Aplysia (NRA, University of Miami) maintains large stocks of live animals and relies on regular shipments of wild-caught individuals to maintain genetic diversity. This is labor and cost-intensive, and environmental changes could alter the availability of wild animals increasing the need to preserve this genetic resource. One solution is vitrification, ultra-fast cooling which produces an amorphous glass that minimizes damage to cells. Aplysia californica presents …

Do Fishery Meeting Attendees Represent The Fishing Industries?, Dominique Seibert

LSU Master's Theses

Public meetings are a highly utilized tool for disseminating important or useful information. Many agencies rely on them to reach various stakeholders and community representation at these meetings is important. A substantial amount of research has been conducted on various aspects of public meetings including different techniques, factors impacting attendance, and representativeness, that is attendees’ opinions representing the opinions at-large. A noticeable gap in the research includes information on public fishery meetings, commercial fishing industries, and their members’ participation. With the U.S. commercial fishing industries supporting more than a million jobs and providing more than a 200-billion-dollar economic impact annually, …

Evaluating Vaccine Management Strategies For Edwardsiella Ictaluri Infections In Zebrafish (Danio Rerio), Brandy Malbrough

LSU Master's Theses

Aquaculture is a globally important industry that faces significant challenges due to infectious diseases, which can result in substantial financial losses. In 2011, a new strain of Edwardsiella ictaluri emerged as a major pathogen affecting zebrafish in the ornamental fish industry, leading to high mortality rates and posing a severe threat to the sector. Vaccines provide potential benefits for disease prevention in aquaculture, particularly live-attenuated vaccines (LAVs), which induce strong host immune responses. Bacterial attenuation for vaccine development has evolved from serial passage to more targeted genetic modification techniques. However, regulatory constraints limit the availability of licensed LAVs for aquaculture. …

Morphological And Molecular Characterization Of The Olfactory System In The Formosan Subterranean Termite, Paula Castillo

LSU Doctoral Dissertations

The Formosan subterranean termite, Coptotermes formosanus, is a eusocial insect species. Its members live in colonies consisting of reproductive (queen and king) and non-reproductive individuals (workers and soldiers). Olfaction is an essential sense for the social life of many insects. However, in termites, little is known about how olfactory cues are perceived in the peripheral sensory system (antennae) and processed in the central nervous system (brain) to elicit different behavioral responses across castes. In this study, we investigated the olfactory system in all castes (soldiers, workers, and reproductive alates), from the antennal and brain morphology to the antennal gene …

Evaluation Of Salvinia Weevil Establishment, Dispersal, And Environmental Pressures Impacting The Giant Salvinia Biological Control Program, Korey Danielle Pham

LSU Master's Theses

Giant salvinia (Salvinia molesta Mitchell), an invasive free-floating aquatic fern, invaded the Toledo-Bend reservoir along the Texas-Louisiana border in the 1990s. The rapid spread threatens critical ecosystems, economies, and cultural services by altering water quality, and impacting fishing, hunting, and navigation. To combat this issue, the LSU AgCenter has been rearing and distributing the salvinia weevil (Cyrtobagous salviniae Calder and Sands), which has demonstrated effectiveness in reducing giant salvinia populations within a matter of months to a few years. The first study assessed the impact of propagule pressure on salvinia weevil effectiveness in outdoor mesocosms and revealed that …

Evaluation Of A Nutritional Calming Supplement For Stress Management In Beef Cattle, Randall Mallette

LSU Master's Theses

Two studies were conducted to determine the efficacy of two formulations of a nutritional calming product, Placid 1.0 and Placid 2.0, at keeping beef cattle in a calm state when exposed to environmental factors that put them into an excited state. In the pilot study, nine crossbred beef heifers were orally drenched daily for three days with 60 mL of their respective treatments, pen scores and exit scores were recorded, and blood was collected for cortisol analysis. There were no treatment effects for either treatment on any of the measured behavioral parameters or serum cortisol concentrations.

The products were …

Integrating Germplasm Repositories Into Oyster Aquaculture Systems At The Pathway, Center, And Network Levels, Sarah R. Bodenstein

LSU Doctoral Dissertations

Germplasm repositories offer many potential benefits to commercial farm operations, including preserving genetic resources and increasing production capabilities. Aquaculture industries have yet to take advantage of repository storage despite decades of research evaluating cryopreservation protocols. Eastern oysters (Crassostrea virginica), for example, are a useful research species when addressing this problem. Oysters are an economically important aquaculture species and a high-throughput cryopreservation method for oysters already exists. To address the gap between protocol research and commercial application a different approach is necessary that can analyze the requirements of repository development at multiple organizational levels. The goal of this dissertation was to …

Gulf Sturgeon Mesohabitat Use And Movement In The Lower Pearl River Louisiana-Mississippi, Amanda Popovich

LSU Master's Theses

After spring migrations to natal rivers Gulf Sturgeon Acipenser oxyrinchus desotoi reside in freshwater holding areas prior to fall emigrations to nearby estuaries. Limited published information on the physical habitat characteristics of these holding areas is available, especially for juvenile fish in the western portion of the Gulf Sturgeon’s distribution. To further investigate freshwater occupancy and movement patterns, 32 acoustic receivers were deployed from late April to October of 2021 and 2022 in 1600-m reaches distributed throughout the lower Pearl River, Louisiana-Mississippi, the westernmost river within their distribution. Generalized linear mixed models and multi-state models were used to determine what …

Recombinant Dna Vaccine Design As A Potential Strategy Against Bovine Foot And Mouth Disease Virus (Fmdv), Taylor Haynie

LSU Master's Theses

Foot-and-mouth disease virus (FMDV) is the causative agent for foot-and-mouth disease (FMD) that infects primarily cloven-hoofed animals, the majority of which are domesticated cattle and other important livestock. FMD is highly transmissible and found in all secretions and excretions of infected animals. North America, Europe, and Australia have successfully eradicated the virus with the help of a well-defined fiscal infrastructure and access to successful control measures. Less developed regions, including many Asian and African countries, have maintained an endemic status for decades. African territories are of particular concern because of the indigenous African Buffalo population that serves as an important …

A Subspecies-Level Database Of Amazonian Bird Distributions, With Inferences On Suture Zones And Conservation, Marco Antonio Rego

LSU Doctoral Dissertations

Amazonia has the largest and most biodiverse tropical forest on the planet. However, the distributions of its species are still poorly understood, even for well-studied vertebrates such as birds. Available distribution maps for Amazonian birds often lack accuracy in delimiting the area where species occur. Existing distributional information for Amazonian birds is often limited to species-level level taxonomy, even though many Amazonian bird subspecies represent biological species. Here, I investigate the geographic distributions of 4,148 bird taxa (species and subspecies) using museum scientific specimens as the primary source of data. To build the data base I use more than 600,000 …

Searching For The Soldier Pheromone: Behavioral Effects Of Soldiers And Soldier-Produced Chemicals In The Formosan Subterranean Termite, Coptotermes Formosanus (Blattodea: Rhinotermitidae)), Joseph Mccarthy

LSU Master's Theses

The Formosan subterranean termite, Coptotermes formosanus, is a eusocial insect and an invasive urban pest. Colonies function through a division of labor among castes (i.e., queens and kings, workers, and soldiers). Though soldiers are energetically expensive to maintain, C. formosanus has a relatively large soldier caste (~10% of the colony). Soldiers are physically unable to collect food or build tunnels but are regularly found with foraging workers. In some species, soldiers influence the worker foraging behavior. In C. formosanus, aside from defense, the roles soldiers play remains unknown. In this study, we determined if soldiers influence …

Fish And Invertebrate Community And Trophic Structure In The Gulf Of Mexico Coastal Plains Watersheds Across Varying Hydrologic Connectivity., Erin Elizabeth Thayer

LSU Doctoral Dissertations

Subtropical Northern Gulf of Mexico coastal plains watersheds tend to have mild seasonal temperature, low topography, and fine, mostly homogenous substrate sizes; these watersheds may not follow fish and invertebrate community patterns predicted by established lotic paradigms because those paradigms tend to describe communities in either temperate or tropical regions. However, the bases of most generally accepted lotic paradigms involve evaluation of allochthonous and autochthonous contributions to lotic ecosystems via three hydrologic connectivity dimensions including vertical (hyporheic and shallow groundwater), lateral (floodplain), and longitudinal (upstream and downstream). My dissertation goals were to explore these three dimensions within Louisiana coastal plains …

Immunohistochemical Localization Of Kisspeptin And Its Receptor In The Equine Ovary, Bryce M. Gilbert

LSU Master's Theses

Kisspeptin is recognized for its role as the gatekeeper of reproduction in most mammalian species. However, its role in regulation of reproduction at the ovarian level is poorly understood in the horse. In this study, ovaries from follicular phase, luteal phase, anestrous period, and mares treated with ECP-sulpiride were subjected to immunohistochemistry to characterize kisspeptin-10 (Kp10) and its receptor (Kiss1r) protein expression throughout each reproductive stage and follicle type. Kisspeptin and receptor staining was detected in all follicle types (primordial, preantral, and antral) throughout all reproductive stages, as well as oocytes, corpora lutea, and ovulation fossa. The pattern of Kp10 …

Characterizing Habitat Suitability For Gulf Sturgeon (Acipenser Oxyrinchus Desotoi) In Southern Louisiana, Jenna N. Brogdon

LSU Master's Theses

A generalized additive modeling (GAM) framework was used to characterize fish-habitat relationships and develop habitat suitability maps to predict spatiotemporal and ontogenetic shifts in Gulf sturgeon distribution within an impacted estuary in the northern Gulf of Mexico, Lake Pontchartrain. Gulf sturgeon (n = 103) were fitted with acoustic transmitters in the Pearl River during the early summer and fall from 2013 to 2018, and an array of acoustic receivers (n = 81) was used to monitor Gulf sturgeon habitat use and movement in the estuary from 2016 to 2019. Daily presence data from the telemetry array were paired with environmental …

Developmental Competence Of Oocytes Derived From Seasonally Anovulatory Mares Treated With Estradiol And Sulpiride, Michelle O. Vetter

LSU Master's Theses

Over the course of two years (2021-2022), two experiments were conducted during the nonbreeding seasons to evaluate the in vitro developmental potential of oocytes derived from seasonally anovulatory mares treated with ECP-sulpiride. The objective of experiments 1 and 2 were to compare pooled recovery and maturation rates of oocytes from mares treated with estradiol cypionate (ECP) and sulpiride with oocytes collected from naturally transitional mares (controls). Cleavage rates of oocytes subjected to intracytoplasmic sperm injection (ICSI) were compared only in experiment 2. In experiments 1 and 2, a total of 36 light horse and pony-cross anovulatory mares were used. Treatment …