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An Intersection Of Science & Art: Vitrification Approaches And Open-Fabricated Tools For The Biomedical Model Sea Hare, Aplysia Californica, Allyssa M. Oune Nov 2023

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 Oct 2023

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 Jul 2023

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. …


Evaluation Of A Nutritional Calming Supplement For Stress Management In Beef Cattle, Randall Mallette Jul 2023

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 Apr 2023

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 Apr 2023

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 Mar 2023

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 …


Searching For The Soldier Pheromone: Behavioral Effects Of Soldiers And Soldier-Produced Chemicals In The Formosan Subterranean Termite, Coptotermes Formosanus (Blattodea: Rhinotermitidae)), Joseph Mccarthy Nov 2022

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 Nov 2022

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 Oct 2022

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 Aug 2022

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 Jul 2022

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 …


Evolution Of Freshwater Fishes In The Northern Neotropics, Diego Elias Jul 2022

Evolution Of Freshwater Fishes In The Northern Neotropics, Diego Elias

LSU Doctoral Dissertations

The northern Neotropics (NN) represents one of the most geologically-complex regions on the planet, composed of island-like geological blocks that have undergone multiple episodes of isolation and connectivity at various geological times. The riverscapes of the NN harbor a unique assemblage of freshwater fishes. In contrast to the freshwaters systems of South America, which are dominated by ostariophysan lineages, the aquatic systems of the NN are dominated by lineages of two families: Cichlidae (cichlids) and Poeciliidae (livebearers). It has been suggested that the geologically complex nature of the region allowed ancestors of cichlids and livebearers to colonize and radiate within …


Insights Into The Speciation Process From Genomic And Phenotypic Analysis Of An Avian Hybrid Zone In Amazonia, Glaucia Christina Del-Rio Jul 2022

Insights Into The Speciation Process From Genomic And Phenotypic Analysis Of An Avian Hybrid Zone In Amazonia, Glaucia Christina Del-Rio

LSU Doctoral Dissertations

Understanding the outcome of secondary contact is essential to shed light on the mechanisms governing species formation and maintenance. In Amazonia, closely related bird taxa with limited dispersal abilities are often separated by rivers, which presumably act as dispersal barriers. However, at the headwaters, rivers cease to be dispersal barriers, and this generates opportunities for secondary contact. In my dissertation, I studied genomic mechanisms associated with phenotypic differences, mitochondrial DNA structure, and putative reproductive barriers between two hybridizing Amazonian bird species in the genus Rhegmatorhina, a group of antbirds that find their arthropod prey exclusively by following army-ant swarms. …


Breeding Ecology Of Mottled Ducks In Southwestern Louisiana, Elizabeth Sophia Bonczek Jul 2022

Breeding Ecology Of Mottled Ducks In Southwestern Louisiana, Elizabeth Sophia Bonczek

LSU Doctoral Dissertations

Mottled ducks are a resident species found in the southern United States that rely on coastal marsh and associated habitat to fulfill the needs of the entirety of their annual cycle. Population monitoring has revealed declines in western Gulf Coast (WGC) mottled ducks since 2008. Mottled duck populations are influenced by survival and recruitment, and changes in these factors may contribute to population declines. The overarching goal of this project was to identify the mechanisms potentially limiting WGC mottled ducks.

I captured adult female mottled ducks during molt on Rockefeller Wildlife Refuge and adjacent lands in southwestern Louisiana from 2017–2019. …


Assessment Of The Effect Of Acepromazine On Insulin Tolerance Tests (Itt) In Dairy Heifers, Mya Catherine Orantes Apr 2022

Assessment Of The Effect Of Acepromazine On Insulin Tolerance Tests (Itt) In Dairy Heifers, Mya Catherine Orantes

Honors Theses

No abstract provided.


Effects Of Pine Straw As A Dietary Supplement For Internal Parasite Control In Pasture Raised Meat Goats, Landry M. Higgins Apr 2022

Effects Of Pine Straw As A Dietary Supplement For Internal Parasite Control In Pasture Raised Meat Goats, Landry M. Higgins

Honors Theses

No abstract provided.


The Effects Of Dietary Interventions On Adverse Outcomes In Obese, Preeclamptic-Like Bph/5 Female Mice, Morgan Alston Apr 2022

The Effects Of Dietary Interventions On Adverse Outcomes In Obese, Preeclamptic-Like Bph/5 Female Mice, Morgan Alston

Honors Theses

No abstract provided.


The Design, Construction, And Testing Of A Recombinant Dna Vaccine For Brucella Abortus And Brucella Melitensis, Stephanie Lynn Korle Mar 2022

The Design, Construction, And Testing Of A Recombinant Dna Vaccine For Brucella Abortus And Brucella Melitensis, Stephanie Lynn Korle

LSU Doctoral Dissertations

Brucella spp. are a bacterium that cause brucellosis, a zoonotic disease, which is commonly seen in cattle, sheep, goats, swine, and canines. Brucellosis is a problem worldwide, although it is eradicated in some countries (Garin-Bastuji et al. 1998). The reason for designing recombinant DNA (rDNA) vaccines opposed to utilizing the live-attenuated vaccines on the market is that they cannot be given to pregnant animals without potentially causing abortion, while an rDNA vaccine should be safe for pregnant animals since it does not contain viable bacteria. Also, there are no serological tests that can accurately distinguish between an animal vaccinated …


Brood Abundance And Invertebrate Availability In Crop-Dominated Landscapes In The Prairie Pothole Region, Catrina V. Terry Nov 2021

Brood Abundance And Invertebrate Availability In Crop-Dominated Landscapes In The Prairie Pothole Region, Catrina V. Terry

LSU Master's Theses

The Prairie Pothole Region (PPR) is the most important region for ducks in North America, producing over half the ducks on the continent, and it is a priority landscape for wetland and grassland conservation. Agricultural expansion has changed the PPR, and the majority of grasslands and potholes have been converted into row-crops. The loss of nesting habitat has directly caused nest success to decline. Most of the remaining wetlands are surrounded by row-crops, and are considered lower quality because they receive runoff of sediment and chemicals, which may decrease primary forage for young ducklings as well as inhibit wetland vegetation. …


A Modular Open-Technology Device To Measure And Adjust Concentration Of Sperm Samples For Cryopreservation, Nikolas C. Zuchowicz Sep 2021

A Modular Open-Technology Device To Measure And Adjust Concentration Of Sperm Samples For Cryopreservation, Nikolas C. Zuchowicz

LSU Master's Theses

Repositories for aquatic germplasm can safeguard the genetic diversity of species of interest to aquaculture, research, and conservation. The development of such repositories is impeded by a lack of standardization both within laboratories and across the research community. Protocols for cryopreservation are often developed ad hoc and without close attention to variables, such as sperm concentration, that strongly affect the success and consistency of cryopreservation. The wide dissemination and use of specialized tools and devices can improve processing reliability, provide data logging, produce custom hardware to address unique problems, and save costs, time, and labor. The goal of the present …


Gain-Of-Function Polymorphisms In Human Inflammasomes: Implications For Cystic Fibrosis, Duane Jeansonne, Samithamby Jeyaseelan Aug 2021

Gain-Of-Function Polymorphisms In Human Inflammasomes: Implications For Cystic Fibrosis, Duane Jeansonne, Samithamby Jeyaseelan

Faculty Publications

No abstract provided.


Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam Jul 2021

Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam

LSU Master's Theses

Eastern oysters (Crassostrea virginica) provide valuable ecosystem services and support a productive commercial industry in the northern Gulf of Mexico. Declining abundance from water quality changes and other factors drives development of management and restoration strategies focused on a comprehensive, metapopulation approach. Identifying oyster resource zones based on water quality combined with selective breeding of oysters adapted to specific conditions provides strategies to support aquaculture development and ensure resilient oyster populations and high production. Using 2015-2019 satellite-derived continuous salinity and temperature data for coastal Louisiana, this work created maps defining oyster resource zones supportive of (1) broodstock sanctuary …


Incorporating Life Into Living Shorelines: Can Gulf Ribbed Mussels Reduce Shoreline Erosion And Enhance Restoration Practices?, Jordan Logarbo May 2021

Incorporating Life Into Living Shorelines: Can Gulf Ribbed Mussels Reduce Shoreline Erosion And Enhance Restoration Practices?, Jordan Logarbo

LSU Master's Theses

The gulf ribbed mussel (Geukensia granosissima) exists throughout the Gulf of Mexico and influences biotic and abiotic environmental attributes as an ecosystem engineer. Ribbed mussels are an important component of marsh ecosystems providing services including filtering particulate matter, depositing and transforming nutrients in the system, increasing soil strength via byssal threads and providing structure via their shells.

The spatial distribution of mussels along the marsh edge of Sister Lake, LA was investigated via a broad survey of 150 sites, in relation to elevation, exposure and vegetation percent cover. This survey was followed by a second survey at a …


Effects Of Microtubule Stabilizing And Recovery Agents On Vitrified Bovine Oocytes, Emily Dzekunskas Mar 2021

Effects Of Microtubule Stabilizing And Recovery Agents On Vitrified Bovine Oocytes, Emily Dzekunskas

LSU Master's Theses

Oocyte vitrification, while beneficial for research and species conservation, has limited success due to cryoinjury to the meiotic spindle. This study aimed to evaluate treatments to improve meiotic spindle recovery after vitrification by treating bovine oocytes with either a microtubule stabilizing agent, or a microtubule recovery agent. In the first two experiments, Taxol and epothilone B were used to treat bovine oocytes before vitrification. Both compounds have microtubule stabilizing properties and are known antimitotic compounds commonly used in cancer treatment. Oocytes were incubated with one of the microtubule stabilizing agents for 15 minutes before vitrification at one of three concentrations …


Sexually Dimorphic Oxytocin Receptor-Expressing Neurons In The Anteroventral Periventricular Nucleus Regulates Maternal Behavior, Kaustubh Sharma Nov 2020

Sexually Dimorphic Oxytocin Receptor-Expressing Neurons In The Anteroventral Periventricular Nucleus Regulates Maternal Behavior, Kaustubh Sharma

LSU Doctoral Dissertations

The neurohypophysial hormone oxytocin is involved in the regulation of social behaviors, including social recognition, pair bonding, and sex-specific parental behaviors in a variety of species. Oxytocin triggers these social behaviors by binding to oxytocin receptors (OXTR) in various parts of the brain. Oxytocin-induced sex-typical behavior, therefore, suggests a sexual dimorphic distribution of OXTR in the brain. In recent years, the oxytocin system in the brain received tremendous attention as a potential pharmacological target for treatment of many psychiatric disorders, such as anxiety, autism spectrum disorders, and even sex-specific psychiatric disorder like postpartum depression (PPD). An important problem and a …


The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson Oct 2020

The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson

LSU Master's Theses

Southern Flounder, Paralichthys lethostigma, are a coastal, estuarine-dependent flatfish species that inhabits the Southeastern US Atlantic Ocean and Gulf of Mexico. Throughout their range, Southern Flounder are exploited by both commercial and recreational fisheries. Recently, numerous sources have expressed concerns about Southern Flounder populations, with stock assessments indicating declines in spawning stock biomass and recruitment. To estimate life history traits needed for informed management, such as age, growth, and maturity, I collected 327 Southern Flounder from Louisiana and obtained 14,184 historical records from the Louisiana Department of Wildlife and Fisheries. Using a von Bertalanffy growth equation in a Bayesian …


Fish Community Composition And Structure Near A Freshwater River Diversion In Southeastern Louisiana, Rachel L. Snider Jul 2020

Fish Community Composition And Structure Near A Freshwater River Diversion In Southeastern Louisiana, Rachel L. Snider

LSU Master's Theses

Gulf of Mexico estuaries, particularly in Louisiana, are among the world’s most productive, with landings of commercially- and recreationally-important species exceeding all other contiguous US states. Coastal wetlands are disappearing at an alarming rate because they have been impounded from Mississippi River water and sediment. Although controversial, one proposed solution is to re-route the Mississippi River through diversions and siphons to supply the freshwater and sediments necessary to rebuild vanishing wetlands, particularly in Barataria Bay and Breton Sound, LA. This strategy is one approach outlined in the Louisiana Coastal Master Plan. This project aimed to describe the composition and structure …


Sperm Decondensation And Male Pronuclear Formation In Bovine Intracytoplasmic Sperm Injection, Lauren Gatenby Jun 2020

Sperm Decondensation And Male Pronuclear Formation In Bovine Intracytoplasmic Sperm Injection, Lauren Gatenby

LSU Master's Theses

This study assessed the effects both DTT and progesterone have on bovine spermatozoa to induce decondensation or the acrosome reaction in order to facilitate male pronuclear formation after ICSI. Sperm prepared by swim-up in a 5 mM concentration of DTT displayed time dependent morphological changes resulting in decondensation over a 6-hour period. An estimated 90% of treated sperm displayed early changes in morphology after the second hour of incubation. Sperm displaying partial decondensation of the nucleus was estimated as 42% by the 3rd hour and increased to 62% by the 5th hour of incubation. Fully decondensed sperm or …


Louisiana Beef Cattle Marketing Strategies, Adam Barrilleaux Apr 2020

Louisiana Beef Cattle Marketing Strategies, Adam Barrilleaux

LSU Master's Theses

The purpose of this study was to estimate the financial costs and returns of selected marketing strategies for cattle producers in the state of Louisiana. Cattle for the project were from the Louisiana State University Agricultural Center and commercial producers. Cattle were grouped by weight and sex and vaccinated, castrated, and handled using standard best management practices. The standard marketing practice for weaned calves in Louisiana of selling weaned animals at local stockyards was compared against alternative marketing of preconditioned calves through video auctions or after feedlot finishing. Feedlot cattle were sold both on live weight value and carcass weight …