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Water chemistry characterization and component performance of a recirculating aquaculture system producing hybrid striped bassEaster, Christopher 10 October 2009 (has links)
Eight identical and independent pilot scale recirculating aquaculture production systems were populated with fingerling hybrid striped bass <i>(Morone chrysops</i> female x <i>Morone saxatilis male</i>). Three population densities were established with two replicates at 132 fishlm3 and three replicates each at 66 and 33 fishlm3.
Water chemistry and water quality characteristics were monitored throughout the 228 day growth trial for all eight systems. A system component performance analysis was done for both the multi-tube solids clarifier and rotating biological contactor (RBC).
Water chemistry and water quality analysis included dissolved oxygen (DO), alkalinity, ions, carbonaceous biochemical oxygen demand (CBODS), chemical oxygen demand (COD), dissolved organic carbon (DOC), total suspended solids (TSS), volatile suspended solids (VSS), total ammonia nitrogen (TAN) , nitrite and nitrate. The major ions present were chloride, nitrate, sulfate, phosphate, sodium, calcium, magnesium and potassium. Trace levels of TAN, nitrite, iron and copper were also observed. Sodium, calcium and chloride levels were controlled based on a preplaned water exchange and chemical management method. TAN, nitrite and nitrate levels increased over time with increasing feed rates but never reached levels toxic to the fish population. CBODS,COD, DOC, TSS and VSS increased over time increasing as a function of increasing feed rates. No correlation was observed between fish mortality or fish growth rates for the range of organic and solids parameters observed during this study. On average 67% of the TSS present was between 1.5 and 30 microns in size. Diurnal cycles were observed for DO, TAN and alkalinity. The magnitude of these cycles were population dependent.
Multi-tube clarifiers removed an average 56% of all suspended solids in a single pass with 81 % removal efficiency for particles above 70 microns in size. Analysis of the system effluent generated by the clarifier indicates a high degree of similarity between the aquaculture effluent and standard municipal waste on a nutrient basis but with much higher levels of nitrogen and phosphate species.
RBC nitrification performance was fitted to an empirical equation. A nearly constant TAN removal rate was observed over the range of mass loading experienced in this growth trial. This implies that within a reasonable range higher flow rates resulting in higher mass loading will yield higher TAN removal rates for a given RBC. / Master of Science
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A mathematical model for simulating the bioenergetics and growth of largemouth bass (Micropterus salmoides)Thorn, Timothy L. January 1983 (has links)
Observed growth in weight of an individual fish is the result of an interaction between the environment and the fish's bioenergetic system. A species-specific model is presented which simulates the bioenergetics and growth of largemouth bass (Micropterus salmoides). The model is used to simulate individual growth with changes in the annual temperature regime and relative levels of prey availability. Interaction among temperature, prey availability, and individual size are examined with the model in terms of their influence on growth.
Preliminary tests with the model produced an exponential long term growth pattern which is contrary to the conceptualized trend of individual fish growth. Larger weights are produced by a southern temperature regime because of a longer growing season. Variations in the relative abundance and state of availability suggests an unstable system at limiting levels.
Analysis of the interaction between temperature and prey availability indicates a stable maximum growth temperature above limiting levels of prey availability while the temperature range for positive growth narrowed as prey availability declined. At limiting prey levels, the temperature range for positive growth narrowed and maximum growth temperatures declined as individual size increased in the temperature-individual size interaction.
The model is tested against observed growth data for the 1975 year class of largemouth bass inhabiting West Point Reservoir, Alabama-Georgia. Simulated weights underestimate the observed weights for the first and second years by 25% and 21%, respectively. An alternative equation for caloric density is developed and employed to improve the model's reality and accuracy. / M.S.
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Genetic Marker-Assisted Management of Virginia Sport FishesHarris, Sheila Catherine 20 May 2020 (has links)
Molecular genetic markers can be used to assess genetic diversity, assign parentage, quantify inbreeding, and demonstrate structuring of populations across a system. Striped Bass Morone saxatilis, and Walleye Sander vitreus, are widely sought gamefishes in the Commonwealth of Virginia. Striped Bass along the Atlantic Coast and within the Roanoke River drainage exhibit low genetic variation. Screening 12 microsatellite DNA markers across the range to define population genetic structure, I found that anadromous populations in the Southeast and the Chesapeake Bay were differentiated from landlocked populations in the Roanoke River basin, with an average FST of 0.066. Range-wide, Striped Bass are differentiated between the landlocked and anadromous populations, which need to be managed separately. Within stocked populations in the Roanoke River basin, there have been impacts stemming from small numbers of broodstock propagated, and inter-individual relatedness is ~20% within stocked reservoirs. Walleye across the eastern native range were screened to better understand evolutionary history and to identify native marker alleles for the upper New River population. Population genetic variation at eight microsatellite loci showed differentiated stocks in Alabama, Mississippi River, Eastern Highlands (Tennessee, New, and Ohio Rivers), and the Great Lakes drainages. All estimates of effective numbers of breeding individuals were under 25, and all populations within all watersheds had ~15-20% inter-individual relatedness, likely effects of both natural demographic processes and stocking. The extent of Eastern Highlands Walleye includes both the Ohio and Tennessee basins. Although I did not identify new marker alleles for native New River Walleye, I determined that marker-assisted selection has increased the frequencies of existing marker alleles for the native stock. Application of the results of this project will contribute to better fisheries management for both of these important species. / Master of Science / Population genetics have proven useful for defining the most appropriate units for conservational management across a variety of species. Molecular genetic markers can be used to assess genetic diversity, assign parentage, quantify inbreeding, and demonstrate structuring of populations across a system. Striped Bass Morone saxatilis and Walleye Sander vitreus are both widely sought gamefishes in the Commonwealth of Virginia. I applied population genetic approaches to recognize genetically distinct groups of populations and to recommend genetically cognizant management practices. Striped Bass across the Atlantic Coast and in the Roanoke River drainage exhibit low genetic variation. After screening variation at 12 DNA markers, I found that Striped Bass are differentiated between landlocked and migratory populations, which need to be managed separately. Within stocked populations in the Roanoke River basin, there have been impacts stemming from propagation of small numbers of broodstock, and propagation and stocking practices will need to be changed to reduce apparent inbreeding depression. Walleye populations across the eastern native range were screened to better understand evolutionary history and to seek new marker alleles for the native upper New River population. After screening genetic variation at eight DNA marker loci, I identified four evolutionarily distinct stocks of Walleye across eastern North America. Although I did not identify new marker alleles for native upper New River native Walleye, I showed that marker-assisted selection has increased the frequencies of existing marker alleles over the past twenty years. The results of this project can contribute to better fishery management strategies for both of these important gamefish species.
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Dietary Selenium in Cultured Hybrid Striped BassCotter, Paul 26 September 2006 (has links)
As aquaculture continues to contribute high quality protein to a greater proportion of the worlds growing population, fish producers have been pressured to increase overall production. However, associated with elevated production is greater stress due to crowding, reduced water quality, and other factors. These stressors impact the health and welfare of the farmed animal which has become of increasing concern to a more environmentally aware and health conscious consumer. New strategies must therefore be developed and adopted by the aquaculture industry to counteract negative consumer perceptions of industrial fish production while also stabilizing the industry.
Better nutrition may enhance disease resistance of farmed fish, while fillet accumulations of specific health-related nutrients may simultaneously add value to the final product. This thesis summarizes research undertaken in an effort to enhance the nutritional value of fish by increasing fillet levels of selenium (Se). In addition, various biomarkers of fish health (lysozyme, ceruloplasmin and glutathione peroxidase (GSH-Px) activities), were examined to determine whether dietary Se supplementation had a positive impact upon fish immunocompetence. Moreover, the effect of vaccination was also examined using lysozyme and growth as indicators of fish performance. Hybrid striped bass (HSB), the fourth most valuable farmed fish and fifth in tonnage produced in the United States, were employed as a model animal.
Se, an essential component of the antioxidant enzyme, glutathione peroxidase with many established health benefits was supplemented to HSB diets at various concentrations but was found to be without effect upon serum immune proteins or GSH-Px activity. This finding likely reflected the use of fishmeal within the dietary formulation, which possessed relatively high Se levels, together with sufficient storage of tissue Se within the experimental animals. Nevertheless, these studies determined that organic sources of Se were more efficiently accumulated in HSB muscle than traditional inorganic sources. A linear response occurred up to the highest dose used (3.2 mg kg⁻¹) over a 6 week study. Fillet Se accumulation (r²=0.95) proved to be a better indicator than the liver (r²=0.87).Se enhanced fish therefor appear to offer a route of entry for fish producers into the lucrative designer food market - especially since many hundreds of millions of people worldwide are believed to be Se-deficient. Studies undertaken with Se-deficient HSB confirmed findings from the aforementioned research and also indicate that Se-enhanced fillets might be produced using a finishing feed containing 1.5 mg Se kg⁻¹ 6-8 weeks prior to harvest. Accumulation of Se using this strategy resulted in a 100g portion of HSB fillets containing between 33-109 µg Se, amounting to a dietary intake of between 25-80 µg Se; a level that would satisfy present daily intake recommendations.
Vaccination of HSB with a Streptococcus iniae oil-in-water vaccine was examined for its potential negative impacts upon HSB production performance. Vaccinated fish did not exhibit any significant reductions in growth but microarray studies revealed that together with many hundreds of genes, four immune-related genes were impacted by this procedure. This thesis discusses the results obtained with regard to their practical implications to the industry and welfare of cultured fish. / Master of Science
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Historically informed thoroughbass theory: the structure, classification, & movement of chords according to German thoroughbass treatises of the eighteenth centuryHaskell, Sheridan 17 May 2024 (has links)
Theoretical constructs latent in thoroughbass treatises of the 18th century can serve students of thoroughbass today. In the following work, I draw from Johann David Heinichen’s Der General-Bass in der Composition (1728), David Kellner’s Treulicher Unterricht im General-Baß (2nd edition, 1737), Johann Mattheson’s Der vollkommene Capellmeister (1739), Friedrich Wilhelm Marpurg’s Handbuch bey dem Generalbasse und der Composition, Carl Philipp Emanuel Bach’s Versuch über die wahre Art das Clavier zu spielen (part 2, 1762), and recent scholarship in the areas of Partimento theory, Musica Poetica, and early music theory in general, to demonstrate how the many thoroughbass figures can all be contextualized in an historically informed theoretical framework. In the first two chapters, (1) thoroughbass figures are analyzed as having an internal hierarchy of primary and auxiliary intervals, allowing chords to be understood both vertically and linearly; (2) chords are localized in the major and minor modes according to bass scale steps; and (3) the various contrapuntal procedures associated with dissonant chords used in both the strict style (stylus gravis) and freer styles (stylus luxurians communis and stylus luxurians theatralis) are analyzed as German musical-rhetorical figures. In chapter 3, these three theoretical constructs are used to organize an extensive collection of dissonant chord progressions derived from the aforementioned treatises of Heinichen, Mattheson, Marpurg, and Bach. In chapter 4, I draw from basic elements of partimento theory—namely cadences, sequences, and the Rule of the Octave (regola dell’ottava or règle de l’octave)—to construct a series of exercises; most of these exercises use a relatively strict four-part texture and are illustrated from multiple righthand starting positions to promote flexibility in the student. Finally, in chapter 5, practical matters of thoroughbass realization, namely pragmatic and expressive concerns, are discussed and illustrated with examples from many treatises of the 17th and 18th centuries.
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Striped Bass and Summer Flounder Population Dynamics in the Chesapeake Bay: an Ecosystem Based EvaluationOakley, Josephine Marie 27 March 2024 (has links)
The Chesapeake Bay is the largest estuary in the United States and is highly productive making it a key habitat for species like striped bass and summer flounder. Striped bass and summer flounder have exhibited changes in abundance over recent years within the Chesapeake Bay. There is a lack of understanding of how environmental factors may be impacting striped bass and summer flounder abundance and how other species may be responding to these environmental drivers. To improve our understanding of striped bass, summer flounder and the aquatic community we set out to identify the environmental drives of their abundance changes from local to global scales. The fish community in the Bay has previously shifted due to environmental perturbations, so we also investigate if the community has changed more recently. We used a hurdle model to standardize interannual abundance of fish species caught in the Chesapeake Bay from two sources of fishery-independent trawl survey data. This standardization process led to relative abundance indices for 58 late juvenile to adult species from 2002-2018, and relative abundance indices for 26 juvenile species from 1995-2019. Species with similar and contrary abundance trends with striped bass and summer flounder were identified through a correlation analysis, and life history traits were assessed between species to determine mechanisms of change. We then used nonmetric multidimensional scaling (nMDS) to see if the community structure had drastically changed, the applied a principal response curve (PRC) to investigate the spatial and functional group change of the community. Among the factors examined, sea surface temperature (SST) in the Bay has increased since 2006 based on change point analysis while the mean Bay SST range and gradient have both decreased. Striped bass have had variable abundance in the Bay but exhibited a positive correlation with increasing SST. Summer flounder have declined in abundance since 2006 in the Bay and exhibited a negative correlation with increasing SST. Striped bass and summer flounder had relationships with global climate oscillations such as the winter North Atlantic Oscillation, Atlantic Multidecadal Oscillation, and the Gulf Stream North Wall oscillation. From a community perspective, our results showed that the late juvenile to adult fish community shifted after 2011, which coincided with the freshwater surge due Hurricane Irene and Tropical Storm Lee. The increase in abundance of striped bass, Bay anchovy, and Atlantic menhaden, and decrease in abundance of summer flounder, weakfish, spot, and Atlantic croaker were the main species that contributed to the difference in community structure after 2011. The change in functional group structure after 2011 was defined by a decline in opportunistic demersal fish, and this change was significantly different in the portion of the Bay north of the Potomac River. We did not identify any significant correlation between functional groups and environmental factors but did discover the important relationship that top predators like striped bass and summer flounder have with their key fish prey species, both in presence and population trends. Long term monitoring and further research in to how the community changed over smaller periods and the distribution changes of species could improve our understanding of what is impacting the Chesapeake Bay community to inform better management strategies. / Master of Science / The Chesapeake Bay is an important habitat for many animals, including fish. Of the fish species that inhabit the Bay, striped bass and summer flounder are two highly sought after commercial and recreational species, and are top predators, which means they are economically and ecologically important. Striped bass and summer flounder have exhibited changes in abundance over recent years within the Chesapeake Bay, and there is a lack of understanding what environmental factors may be driving their abundance trends and if other species are responding similarly. To conserve striped bass and summer flounder, management strategies should consider the relationship these species have with their environment and other species. Through this research, we set out to understand what environmental factors are impacting their population trends, and the trends of the aquatic community which can be used to inform effective management decisions for the future. To accomplish our research goals, we first used a hurdle model to determine the interannual abundance of 58 adult and 26 juvenile fish species from 2002-2018 and 1995-2018 respectively. We then investigated whether any environmental factors exhibited relationships with striped bass and summer flounder. Again, through correlation analysis, we identified species with similar and contrary abundance trends with striped bass and summer flounder and compared the traits of these species to try to identify the mechanisms of their abundance trends. To visualize if and how much the fish community composition had changed over time we used nonmetric multidimensional scaling (nMDS), then applied a principal response curve (PRC) to investigate the spatial change and life history trait change in the fish community. The results showed us that striped bass and summer flounder do exhibit relationships with environmental factors. Sea surface temperature (SST) in the Bay has increased, while the range and gradient has decreased, and an increase in the mean SST occurred in 2006. We found that striped bass had variable abundance in the Bay but correlated positively with increasing SST, however summer flounder abundance has decreased since 2006 in the Bay and has a negative correlation with SST. Striped bass and summer flounder exhibited relationships with global climate-oscillations that impact the Chesapeake Bay, making those factors important to consider for their management. The results of the community assessment showed that the late juvenile to adult fish community shifted after 2011. This change in community structure coincided with a decrease in water quality and a freshwater surge in 2011 that was caused by Hurricane Irene and Tropical Storm Lee. After the community shift, striped bass, Bay anchovy, and Atlantic menhaden increased in abundance, while summer flounder, weakfish, spot and Atlantic croaker decreased in abundance. These species were the top species that contributed to the change in community structure. The change in community structure was greatest, and significant in the northern portion of the Bay. From these results we identified the important relationship between predators and prey both in species presence and abundance trends. Striped bass abundance increased alongside an increase of their key prey species, Bay Anchovy and Atlantic menhaden, while summer flounder abundance decreased along with two of their key prey species spot and Atlantic croaker. This research identified environmental factors that contribute to abundance trends of striped bass and summer flounder and highlighted the importance of multispecies interactions within the aquatic Chesapeake Bay community. Long term monitoring and more research into finer scale spatial and temporal changes of fish in the Bay could further improve management recommendations.
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Exigência em lisina pelo "black bass" Micropterus salmoides. / Lysine requirements of largemouth bass Micropterus salmoides.Dairiki, Jony Koji 08 July 2005 (has links)
Os elevados custos atribuídos à nutrição na piscicultura ligam a eficiência alimentar ao sucesso da atividade e à redução do impacto ao meio ambiente. Estudos sobre a nutrição e determinação de exigências nutricionais em aminoácidos são, portanto, ferramentas importantes para a consolidação da piscicultura comercial racional e com viabilidade econômica. A determinação da exigência em lisina para o "black bass" Micropterus salmoides foi feita em ensaio de dose-resposta e os dados coletados foram analisados por meio de três modelos estatísticos: regressão polinomial, regressão segmentada e modelagem matemática específica, para estimar a utilização e exigência dos aminoácidos. Foi utilizada a relação A/E = [(aminoácido essencial ÷ total de aminoácidos essenciais + cistina + tirosina) x 1.000], para estimar as exigências nutricionais dos demais aminoácidos essenciais em relação à lisina determinada no experimento dose-resposta. As unidades experimentais foram constituídas por lotes de 25 alevinos de black bass (1,29 ± 0,03 g; 4,35 ± 0,17 cm) condicionados a aceitar ração seca, alojados em gaiolas de PVC atóxico (abertura de malha 5 mm) com capacidade de 60 L e instaladas em caixas de polipropileno com capacidade de 1.000 L, com troca parcial de água num sistema fechado de recirculação e aeração. Os tratamentos correspondiam aos níveis crescentes de lisina: 1,0; 1,5; 2,0; 2,5; 3,0 e 3,5% na dieta n=4), num delineamento inteiramente aleatorizado (DIA). O modelo estatístico da regressão segmentada foi o modelo mais apropriado para determinação da exigência dietética de lisina para os alevinos de black bass em experimento dose-resposta. A exigência dietética em lisina para peso final, ganho de peso e taxa de crescimento específico foi de 2,1% da dieta ou 4,9% da proteína dietética. A exigência dietética de 1,69% de lisina na dieta ou 3,9% de lisina na proteína condicionou o melhor índice de conversão alimentar. O uso do perfil de aminoácidos corporais do black bass foi adequado como referência para estimar as exigências nutricionais de aminoácidos. / Adequate nutrition of fish stocks interconnects fish feeding efficiency, profitability and mitigation of environmental impact of fish farming. Knowledge on amino acids requirement of farmed fish boosts rationalization and profitability of fish farming systems. This study compares estimation of amino acids requirements of largemouth bass Micropterus salmoides from data of lysine dose-response trials, analyzed through different statistical models: polynomial regression, broken-line analysis and specific mathematical modeling. Amino acids requirements were estimated through the A/E relationship [A/E = (essential amino acid ÷ total essential amino acids + cystine + tyrosine) x 1.000]. Groups of 25, feed-conditioned largemouth bass fingerlings (1.29 ± 0.03 g; 4.35 ± 0.17 cm), were stocked in 60-L cages (5 mm mesh) placed in 1,000-L plastic, indoor tanks, closed circulation system, and fed diets containing 1.0, 1.5, 2.0, 2.5, 3.0, or 3.5% lysine, in a totally randomized experimental design trial (n = 4). The broken-line analysis method yielded more reliable and precise estimations of lysine requirements - 2.1% of diet or 4.9% dietetic protein - for final weight, weight gain and specific growth rate. Best feed conversion ratio was attained with 1.69% lysine in the diet or 4.9% lysine in dietetic protein. Body amino acids profile was an adequate reference for estimation of largemouth bass amino acids requirements.
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The life history and ecology of largemouth bass in Parker Canyon LakeSaiki, Michael K. (Michael Kenichi), 1949- January 1973 (has links)
No description available.
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How do bass enhancement algorithms impact mixing decisions when monitoring on headphones?Enlund, Anders January 2018 (has links)
As music production moves from the big professional studios into small bedroom studios, Headphones become more commonly used for monitoring. This brings a new set of problems based on the limitations of headphones compared to loudspeakers. This research explores how a bass enhancement algorithm impacts the results when mixing low frequency audio on headphones. This is done through a simple mixing experiment where subjects are tasked with balancing the amplitude of a low frequency element in a song, both with and without a bass enhancement algorithm enhancing the headphone monitoring. It is shown that while subjects do not perceive a difference in difficulty with this task, the results differ as subjects overall mix the bass frequencies lower in amplitude when aided by the bass enhancement algorithm. It is concluded that the bass enhancement algorithm is useful in this manner.
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Archéologie, typographie et mise en scène du générique de films : les apports de Kyle Cooper / Main Title Design & graphic artPiri, Sara 25 June 2016 (has links)
Cette thèse propose une étude sur la relation entre les arts graphiques et le cinéma à travers une observation analytique du générique de film en tant que fragment cinématographique hybride présentant un entremêlement ou encore une rencontre entre les éléments graphiques et les éléments filmiques. Par cette étude nous interrogeons le générique d’ouverture de film, de l’apparition de la cinématographie aux expériences plus contemporaines, en suivant l’évolution d’une forme à la fois graphique et cinématographique reposant sur une frontière technique constamment mouvante grâce aux multiples innovations technologiques.Dans ce travail, nous nous intéressons aux fonctions, typologies, typographies et mises en scène du générique d’ouverture, ainsi qu'aux différents éléments le composant, qui s’expriment selon des modalités à la fois historiques, techniques et esthétiques. L’esthétique de la typographie et son évolution font l’objet d’une attention particulière.Cette thèse se concentre particulièrement sur Kyle Cooper et plus spécialement sur le générique d’ouverture de Se7en, remarquable par son style de typographie cinétique ainsi que son incroyable tour de force technique et esthétique.Notre objectif est de démontrer, à travers les développements graphiques et filmiques du générique d’ouverture, à quel point les apports de Kyle Cooper pour l’art de sa conception sont fondamentaux et considérables. Cooper a contribué à la renaissance de l’art du générique de film à la suite de Saul Bass, dans les années 1950. / This thesis proposes a study of the relation between graphic art and cinema through ananalytical approach of film opening credits as a hybrid cinematographic fragment with areunion of graphic elements and cinematographic elements. Through this study, we willanalyze opening credits, from the beginning of cinema until contemporary experiences,following the evolution of a from simultaneously/both graphic and film based on a technicalline constantly shifting with innovations.In this work, we are also interested in fonctions, types, typography and staged opening credits,elements which are expressed according to historical, technical and aesthetic modes. Theaesthetics of typography and its evolution are the subject of a particular attention.This thesis focuses specifically on Kyle Cooper and more precisely on the opening credits ofSe7en with its outstanding style of kinetic typography and its incredible aesthetic andtechnical tour de force.Our goal is to prove the significance of Kyle Cooper’s contribution and why his contributionsfor art of the generic design are so fundamental and substantial across graphic developmentsand opening credits. Cooper had an important part in the rebirth of the art of film credits withSaul Bass in the 1950s.
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