Life Sciences Commons^™

Characterizing Potential Sustainable Energy Feedstocks, Jesse George Thompson

Dissertations

Trap grease offers a promising and less expensive alternative to food grade vegetable oils for biodiesel production, but its commercial marketability could be affected by its intense and offensive odor. Identification, quantitation and eventual elimination of the odorant compounds are vital challenges that need to be addressed before commercialization can be achieved. A rapid method using HS-SPME and GC/MS was developed in this study to identify and quantify the major volatile odorant compounds present in trap grease. The main odorant compounds were identified as short chain free fatty acids (SC-FFA) from C₄ - C₁₀.

Sensory evaluations by …

Life History And Habitat Use Of The Juvenile Alabama Shad (Alosa Alabamae) In Northern Gulf Of Mexico Rivers, Paul Fraser Mickle

Dissertations

The Alabama shad, Alosa alabamae, is an anadromous species that is in decline and has seen extirpations from impoundments as well as decreased water quality. Alabama shad live in the Gulf of Mexico and ascend Northern Gulf of Mexico Drainages to reproduce early in the year (January-May). The juveniles spend the majority of the year in these freshwater systems before emigrating out to the Gulf of Mexico as late as December.

This dissertation focuses on the juvenile life stages that occur within the Northern Gulf of Mexico drainages. Spawning conditions of the river, as well as the habitat and diet, …

Information Acquisition And Sociality Among Migratory Birds, Zoltán Németh

Dissertations

Information use is a key feature of adaptive behavior: the better informed an individual, the better it is able to adjust its behavior to meet the demands of a variable world. Therefore, most animals attempt to reduce environmental uncertainty by gathering information when it is available. However, tracking unpredictable ecological factors may carry costs as individuals invest valuable time and energy in the process of information acquisition. Social learning (i.e., use of social information inadvertently produced by other individuals) enables the individual to gain rapid and more complete assessment of its novel environment. This process may be particularly important for …

Conservation Genetics And Systematics Of Several Turtles Species In The Southeastern United States, Joshua Robert Ennen

Dissertations

Chelonians (i.e., turtles) are an imperiled group of reptiles with about 66% of the recognized species listed as threatened by the IUCN. Most chelonian species have a unique set of life history traits (i.e., longevity, delayed sexual maturity, and low juvenile survivorship), which makes their populations exceedingly sensitive to increases in adult and juvenile moralities. With numerous anthropogenic effects (e.g., habitat alteration, exploitation, and over harvesting) negatively influencing mortality rates, chelonians have experienced global precipitous declines and extinctions.

This dissertation focuses on species within two chelonian genera, Gopherus and Graptemys. Although these two genera are vastly different ecologically, they are …

Experimental Population Dynamics Of Amyloodiniumocellatum In The Spotted Seatrout, Cynoscion Nebulosus, And The Red Snapper, Lutjanus Campechanus, Ignacio Masson

Dissertations

Amyloodinium ocellatum is a parasitic dinoflagellate that infects warm water marine bony fishes and causes high mortalities in aquaculture settings. It has three life history stages: the feeding trophont, the reproductive tomont, and the infective dinospore. This dissertation describes the characteristics of A. ocellatum infections in juvenile spotted seatrout, Cynoscion nebulosus, and red snapper, Lutjanus campechanus, studies the survival and fecundities of the stages in the life cycle of the parasite and presents a population model for A. ocellatum.

At 25°C and 33 ppt, the peak of trophont detachment occurred on day 2 postinfection in spotted seatrout and day 3 …

The Effects Of Dolphin Education Programs On Visitors' Conservation-Related Knowledge, Attitude And Behavior, Lance Joseph Miller

Dissertations

Zoological institutions typically exhibit dolphins in educational programs such as dolphin shows and interaction programs. The goal of these programs is to entertain visitors while increasing their conservation-related knowledge, attitude and behavior towards dolphins and the marine environment. The purpose of the current study was to examine dolphin shows and interaction programs in terms of their effectiveness in meeting these goals. A multi-institutional study was conducted at six different facilities throughout the United States. A repeated measures design was used to examine the knowledge, attitude and behavior of visitors before, immediately after and three months following participation in dolphin shows …

The Effects Of Climate Variability On The Structure Of The Phytoplankton Community In Tumaco Bay, Colombia, Ingrid Garcia-Hansen Honkala

Dissertations

Spatiotemporal variability in the diatom and dinoflagellate community structure and chlorophyll a (chl a) concentrations in Tumaco Bay during the 1993-2005 period was related clearly to seasonal and interannual variability in environmental conditions due to the migration of the Inter-tropical Convergence Zone (ITZC) and the influence of El Nino Southern Oscillation (ENSO) events. A total of 134 species of diatoms that belong to 57 genera, and 78 species of dinoflagellates that belong to 25 genera were identified during the survey. The diatom community was the dominant group in the waters of the bay, being the most abundant with the greatest …

Gene Expression Profiles As Molecular Indicators Of Dissolved Oxygen Stress In Grass Shrimp Palaemonetes Pugio Holthuis 1949, Tiandao Li

Dissertations

Occurrence and severity of hypoxia is increasing in coastal and estuarine environments, and recovery of impacted habitats and living resources is slow. Detection of early biological effects of hypoxia is needed for timely remedial action to be taken. The overall objectives of this research was to develop molecular indicators of dissolved oxygen stress to assess the biological impact of hypoxia in coastal estuaries and validate their use through a combination of laboratory and field studies. To achieve these goals, grass shrimp, Palaemonetes pugio, oxygen-sensitive and hypoxia-tolerant species abundant in estuarine systems, were exposed to hypoxia under controlled laboratory conditions, and …

Yellow Head Virus: Transmission And Genome Analyses, Hongwei Ma

Dissertations

Yellow head virus (YHV) is an important pathogen to shrimp aquaculture. Among 13 species of naturally YHV-negative crustaceans in the Mississippi coastal area, the daggerblade grass shrimp, Palaemonetes pugio, and the blue crab, Callinectes sapidus, were tested for potential reservoir and carrier hosts of YHV using PCR and real time PCR. The YHV replicated in the daggerblade grass shrimp, and was still detectable on 36 d post-inoculation, causing 8% mortality after injection. However, YHV did not replicate in the blue crab. These data suggest that the daggerblade grass shrimp could act as a reservoir host for YHV. Storage conditions of …

Review Of The Genus Polycheria Haswell, A Symbiotic Group Of Amphipods (Crustacea: Dexaminidae) With Descriptions Of New Species From Florida, The Caribbean Sea, And The Indo-Pacific Region, John Milton Foster

Dissertations

Systematics and taxonomy of the dexaminid amphipod genus Polycheria Haswell (Dexamindae: Amphipoda), whose members are cosmopolitan associates of tunicates and sponges, are confused. This is due in large part to the many inadequate and incomplete descriptions and poorly some executed illustrations, especially for the early studies on the group. Previously, 22 nominal species or forms have been described or designated in the literature. The purpose of this study is to critically review and clarify the systematics of this enigmatic genus. Based on personal collections and on specimens from museums, five new species are designated and 22 species or forms are …

A Systematic And Taxonomic Review Of The Family Pseudotanaidae (Crustacea: Peracarida: Tanaidacea) Based Primarily On Morphometry Cladistic Analyses, Jerry Alan Mclelland

Dissertations

Species of the tanaid family Pseudotanaidae, established by Jurgen Sieg in 1973, have been reported from all the world's oceans in depths ranging from near the surface to below 6,000 m. The family currently consists of 46 characteristically small tanaidomorph species residing in two subfamilies, the Cryptocopinae (seven species) and the Pseudotanainae (39 species). Members of the more ancestral Crytocopinae differ from the Pseudotanainae by having females with four rather than three antennule articles and a complete separation of the maxilliped endites. The primary objective of this study was to test the hypothesis that the current structure of the family …

Roosting Ecology Of Rafinesque's Big-Eared Bat, Corynorhinus Rafinesquii, In Southeastern Mississippi, Austin Webb Trousdale Iii

Dissertations

Rafinesque's big-eared bat, Corynorhinus rafinesquii, is considered rare and/or declining throughout its range. Concrete bridges are potentially important roosts for C. rafinesquii, especially in the Gulf Coastal Plain where the species' natural roosts (caves and large hollow trees) are inherently scarce. Successful efforts to monitor and conserve this species must account for its movements among multiple roosts and determine the duration of its roost use (including bridges) at different temporal scales. Therefore, I investigated roosting ecology of C. rafinesquii from 2000-2005 within a mixed hardwood-pine (Pinus spp.) system in southeastern Mississippi. I conducted surveys of concrete bridges to determine phenological …

Characterization Of Membrane Potentials In Vascular Smooth Muscle Of Hagfish, Lamprey And Trout, Prentiss Jones Jr.

Dissertations

The objective of this study was to characterize membrane potentials in systemic arteries of Pacific hagfish, Eptatretus stouti, Rainbow trout, Onchorhyncus mykiss, and Sea lamprey Petromyzon marinus. Previous studies have characterized membrane potentials in piscine tissue. However, these studies utilized non-vascular tissues such as cardiac muscle and skeletal muscle (69, 161). Characterization of membrane potentials in fish vasculature is without precedent in the literature. The hypothesis of this study was that membrane potentials in fish vascular smooth muscle differ little between species when comparable vasculature is evaluated.

Comparative Genomic Analyses And Expression Of A Set Of Overlapping Open Reading Frames Of Frog Virus 3, Type Species Of Ranavirus (Family Iridoviridae), Wendy Guat Hoon Tan

Dissertations

Frog virus 3 (FV3) is the type species member of the genus Ranavirus (family Iridoviridae ). To better understand the molecular mechanisms involved in the replication of FV3, including transcription of its highly methylated DNA genome, the complete nucleotide sequence of the FV3 genome has been determined. The FV3 genome is 105, 903 base pairs long excluding the terminal redundancy. The G+C content of FV3 genome is 55% and it encodes 98 non-overlappingpotential open reading frames (ORFs) containing 50 to 1293 amino acids. Eighty-four ORFs have significant homology to known proteins of other iridoviruses, whereas 14 are unique FV3 ORFs. …

Bufadienolides In The Chemical Defenses Of The Toads, Bufo Americanus And Bufo Fowleri, Catherine E. Merovich

Dissertations

Resource equalization represents the historical and theoretical basis for American school finance and its ideals continue to dominate discussion and practice. During the last decade and a half, the national aspiration for equitable distribution of school finance resources has started a transformation into a derivative notion of adequacy. This equity policy derivative embraces the idea of sufficiency, which in turn implies a standard. The concept of educational adequacy has grown to mean the achievement of high absolute standards. Equity (equalization) theorists measure resource level on a relative basis; each student relative to all others. Adequacy adherents measure student achievement against …

Health Impacts Of Polychlorinated Biphenyls (Pcbs) In Aquatic Organisms, Marla Ann Fisher

Dissertations

Polychlorinated biphenyls (PCBs) are a major contaminant of global extent in water resources and aquatic biota. Due to its high lipid solubility, PCBs fail to be degraded and, therefore, continue to bioaccumulate throughout the environment and food chain. To determine the impact of PCBs on the immune system ofaged and juvenile Japanese medaka (Oryzias latipes), fish were injected with the coplanar PCB congener 126 and examined after 3 and 14 days. PCB 126 produced oxidative stress in both age groups of fish 14 days post-injection; however, juvenile medaka appeared more susceptible than aged fish. Humoral immunity, as determined by antibody …

Identification And Classification Of Coryneform Bacteria Isolated From Bovine Mammary Glands, Jeffrey L. Watts

Dissertations

Coryneform bacteria are frequently isolated from bovine mastitis and these infections are associated with economic losses. Corynehacterium bovis, a lipid requiring species, has been the most frequently isolated coryneform from the milk of infected bovine mammary glands. However, the taxonomic status of this organism is uncertain. In the current study, a polyphasic approach was used to identify coryneform bacteria isolated from bovine mastitis and determ ine the phylogenetic relationships among the identified species. A total of 212 coryneform bacteria isolated from bovine mastitis was obtained from mastitis reference laboratories in the United States and Canada. Presumptive identification based upon …