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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Hepatic microsporidiosis of juvenile grey mullet, Chelon labrosus, with particular reference to parasite development and transmission

Ralphs, James R. January 1984 (has links)
Microgemma hepaticus gen.n.sp.n. is described from the liver of juvenile mullet, Chelon labrosus. Development occurs within xenomas, of diameter 500 µm. These have microvillar surfaces, encircling bands of mitochondria and a reticulate nucleus with many nucleoli. Meronts are plasmodial, divide by plasmotomy and are enclosed within host membranes. Sporonts are free in the cytoplasm and divide by multiple exogenous budding. In sporogenesis the polar sac is formed from golgi vesicles, the manubrium form a dense golgi body and the coiled polar filament form a spiral cisterna linked with the perinuclear membrane system and golgi reticulum. This was also implicated in the formation of the endospore. The polaroplast developed from expanded sacs derived from the manubrium. Uninucleate spores (4.2 x 2.4 µm) possessed 7-9 filament coils and lamellar polaroplast. Foci of infection were associated with liver connective tissue, and histopathological effects limited to adjacent cell necrosis due to pressure atrophy in restricted sites. Host responses result in granuloma formation, with gradual resolution of the lesion. In vitro investigations into spore hatching and viability showed exsporulation was stimulated by oxidising agents and following pretreatment with media of low pH or high osmolarity. Inoculation of spores into RTG cell cultures resulted in observations of a freshly injected sporoplasm, and a plasmodial stage after 72 hours. The ultrastructure of extruded filaments, spore cases and cell penetration is described. Attempts at transmission of the parasite to mullet by stomach tube, feeding of crustacean spore carriers or intraperitoneal injection were unsuccessful and suggested that larval fishes may be the targets of infection. The possible transmission of the parasite in the marine environment is discussed. On the basis of structural and developmental features the genus Microgemma is placed in the family Unikaryonidae. The affiliation of the genus with other fish microsporidia is noted, and wider implications of life cycles and nuclear behaviour to taxonomy and evolution are discussed.
2

The environmental control of oocyte development in the striped mullet, Mugil cephalus

Kelley, Christopher D January 1995 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 132-140). / Microfiche. / xii, 140 leaves, bound ill. 29 cm
3

The wintertime distribution of epipelagic fish eggs alongsouthwestern coast of Taiwan

Chang, Mei-Yu 28 July 2003 (has links)
The purpose of this study is to investigate the wintertime distribution of the fish eggs along the coast of southwestern Taiwan, and to elucidate the fish spawning ground in this area. Moreover, the distribution of striped mullet eggs was also investigated. Two kinds of sampling methods were used in this study, including the surface and vertical trawling. The former applied vertical and oblique towing along the coastline. One sampling was proceeded in November, December 2000, and January 2002 by R/V Ocean Researcher 3 at three transects vertically along the coastline at 10 to 1140 meters deep in Budai, Jiading, and Fangliau. The other was proceeded in November 2000, January, December 2001, and January 2002 parallelly along the coastline at 8 sites from Budai to Fangliau. Besides, the vertical sampling employed in December 2001 and January 2002 by R/V Ocean Researcher 1 in the Taiwan Strait was also analyzed. A total of 5909 fish eggs were obtained from three sampling nets, NORPAC, cyclindricalconic net, and bongo net. All together 4 families, 2 genera, and 2 species of fish eggs, including Myctphiformes Synodontidae, Engraulidae, Tetraodontiformes Tetraodontidae, Scorpaeniformes Triglidae, Muglidae, Clupeiformes chirocentru hyposelosoma, Salmoniformes Polyipnus polli, and Allopus japonicus were found. The fish eggs that couldn¡¦t be identified were sorted into 41 groups by the egg shape, size, and membrane pattern. The four most abundant fish eggs were Muglidae, Engraulidae, dead eggs, and group CV. The fish eggs abundance decreased from inshore to offshore at two transects in Jiading and Fangliau. But it was contrary at the transect of Budai. The same pattern also appeared in the distribution of Muglidae eggs. In the area of inshore water where waterdepth from 15 to 25 meters, higher abundance of total eggs, Muglidae, and Engraulidae were found at the southern site. Muglidae eggs were the most abundant in December, but Engraulidae eggs didn¡¦t appear in this month. 33 fish eggs that might be striped mullet were sampled by OR1 at the edge of 21 ¢J isotherm where China Coastal Current met Kuroshio Current. The hydrographic variation in the year from 2000 to 2001 was affected by tides and topography, whereas in the year from 2001 to 2002 was influenced by Kuroshio. Higher fish eggs abundance found at Linyuan may due to the turbulence of Kao-Ping submarine canyon.
4

Aspects of the Biology of Aeromonas Hydrophilia with Respect to the Striped Mullet, Mugil Cephalus L. in the St. Johns River

Fensch, Gerald E. 01 April 1983 (has links) (PDF)
The aspects of the biology of Aeromonas hydrophila with respect to a striped mullet (Mugil cephalus L.0 nursery were examined. A. hydrophila density in the natural water was found to be strongly correlated with turbidity and weakly correlated with water temperature. No correlations were found between A. hydrophila density and water depth, dissolved oxygen, pH, total alkalinity, specific conductivity, or phytoplankton chlorophyll concentration. A. hydrophila density/g dry weight of stomach content were found to be correlated with chlorophyll concentration/g dry weight stomach content. The survivability of striped mullet after capture was found to be primarily related to stress. Stressed striped mullet tended to become infected by A. hydrophila more readily. The mortality of transported striped mullet was reduced with the use of quinaldine, a fish tranquilizer, and by reducing crowding during transport.
5

Análise descritiva quantitativa (ADQ) e teste de aceitabilidade na avaliação do frescor da tainha (Mugil Liza, Valenciennes, 1836) / Quantitative descriptive analysis (QDA) and acceptability test in evaluating the freshness of mullet (Mugil liza Valenciennes, 1836).

Yamamoto, Beatriz Lie 20 September 2011 (has links)
Diante da importância que o pescado representa como fonte de alimento, e do potencial do Brasil na produção deste, faz-se importante a determinação de métodos de análise que possam fornecer informações seguras sobre seu grau de frescor e que sejam aplicáveis à rotina de inspeção desses produtos. O presente trabalho teve como objetivo caracterizar sensorialmente a tainha (Mugil liza) comercializada na CEAGESP de São Paulo, através da Análise Descritiva Quantitativa (ADQ) e teste de Aceitabilidade, além de determinar os parâmetros sensoriais que podem ser utilizados na avaliação de frescor deste pescado. Através da ADQ, os resultados mostraram que os principais atributos que correlacionam com a avaliação global do frescor foram \"pigmentação característica\", \"delineamento da pupila\" e \"odor característico\", o que indica que estas são características importantes a serem utilizadas para avaliação de frescor de tainha. Entretanto, para os consumidores, os atributos \"aparência\", \"aroma\" e \"firmeza\" são os mais importantes na caracterização de frescor desta espécie. Os dados da ADQ e do teste de aceitabilidade não se correlacionaram significativamente, desta forma, a análise sensorial pode ser uma ferramenta muito útil na avaliação de frescor, desde que utilizado uma equipe previamente treinada. / Because of the fish importance as a food source and Brazil\'s potential in producing this, it is important to determine methods of analysis of this product that can provide reliable information about its degree of freshness and applicable to routine Inspection. This study aimed to characterize mullet (Mugil liza) CEAGESP marketed in Sao Paulo by sensory analysis - Quantitative Descriptive Analysis (QDA) and Acceptability, and to determine sensory parameters that can be used in the evaluation of fish freshness. Through the ADQ, the results showed that the main attributes that correlate with the overall assessment of freshness were \"characteristic pigmentation,\" \"outline of the pupil\" and \"odor\", which indicates that these are important characteristics to be used for assessment fresh mullet. However, for consumers, the attributes \"appearance\", \"aroma\" and \"firmness\" is the most important in characterizing this species freshness. Data from the ADQ and the acceptance test did not correlate significantly in this way, so sensory analysis can be a very useful tool in the evaluation of freshness, since used a previously trained staff.
6

Análise descritiva quantitativa (ADQ) e teste de aceitabilidade na avaliação do frescor da tainha (Mugil Liza, Valenciennes, 1836) / Quantitative descriptive analysis (QDA) and acceptability test in evaluating the freshness of mullet (Mugil liza Valenciennes, 1836).

Beatriz Lie Yamamoto 20 September 2011 (has links)
Diante da importância que o pescado representa como fonte de alimento, e do potencial do Brasil na produção deste, faz-se importante a determinação de métodos de análise que possam fornecer informações seguras sobre seu grau de frescor e que sejam aplicáveis à rotina de inspeção desses produtos. O presente trabalho teve como objetivo caracterizar sensorialmente a tainha (Mugil liza) comercializada na CEAGESP de São Paulo, através da Análise Descritiva Quantitativa (ADQ) e teste de Aceitabilidade, além de determinar os parâmetros sensoriais que podem ser utilizados na avaliação de frescor deste pescado. Através da ADQ, os resultados mostraram que os principais atributos que correlacionam com a avaliação global do frescor foram \"pigmentação característica\", \"delineamento da pupila\" e \"odor característico\", o que indica que estas são características importantes a serem utilizadas para avaliação de frescor de tainha. Entretanto, para os consumidores, os atributos \"aparência\", \"aroma\" e \"firmeza\" são os mais importantes na caracterização de frescor desta espécie. Os dados da ADQ e do teste de aceitabilidade não se correlacionaram significativamente, desta forma, a análise sensorial pode ser uma ferramenta muito útil na avaliação de frescor, desde que utilizado uma equipe previamente treinada. / Because of the fish importance as a food source and Brazil\'s potential in producing this, it is important to determine methods of analysis of this product that can provide reliable information about its degree of freshness and applicable to routine Inspection. This study aimed to characterize mullet (Mugil liza) CEAGESP marketed in Sao Paulo by sensory analysis - Quantitative Descriptive Analysis (QDA) and Acceptability, and to determine sensory parameters that can be used in the evaluation of fish freshness. Through the ADQ, the results showed that the main attributes that correlate with the overall assessment of freshness were \"characteristic pigmentation,\" \"outline of the pupil\" and \"odor\", which indicates that these are important characteristics to be used for assessment fresh mullet. However, for consumers, the attributes \"appearance\", \"aroma\" and \"firmness\" is the most important in characterizing this species freshness. Data from the ADQ and the acceptance test did not correlate significantly in this way, so sensory analysis can be a very useful tool in the evaluation of freshness, since used a previously trained staff.
7

Kefal balığından havyar üretimi ve kalitesinin belirlenmesi /

Karakaş, Yavuz. Diler, Abdullah. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Su Ürünleri Yetiştiriciliği Anabilim Dalı, 2008. / Kaynakça var.
8

Trace metal and metalloid accumulation, distribution, and, speciation in Lake Macquarie, N.S.W., Australia

Kirby, Jason K., n/a January 2005 (has links)
THESIS ORGANISATION This thesis is organised into nine chapters that include seven international and national publications (six accepted and one submitted for publication). The initial overview chapter outlines the justification and direction for this thesis. With the exception of chapter 8 (accepted for publication on the 1st May 2005); all chapters are exact duplicates of published articles in international and national refereed journals (chapters 2 to 7). The initial chapters (2 and 3) presents research findings using a marine fish species, mullet (Mugil cephalus), to measure trace metal bioavailability in Lake Macquarie, NSW Australia. While subsequent chapters (4 to 8) are presenting research under taken to improve the understanding of arsenic cycling in marine and estuarine environments. The final chapter (chapter 9) is a synopsis of the major findings presented in this thesis. Due to the publication nature of this thesis, an unavoidable degree of replication exists within chapters (publications).
9

Dinâmica populacional, análise das concentrações de metais e utilização de biomarcadores em Mugil curema Valenciennes, 1836 do estuário de Santos e do sistema costeiro Cananéia-Iguape, São Paulo, Brasil / Population dynamics, metals concentrations analysis and use of biomarkers in Mugil curema Valenciennes, 1836 from Santos estuary and Cananeia-Iguape coastal system, São Paulo, Brazil

Fernandez, Wellington Silva 13 December 2011 (has links)
O presente estudo teve como objetivo principal compreender a dinâmica populacional de Mugil curema em duas regiões distintas, tanto sob o ponto de vista oceanográfico como no de ocupação humana, e os possíveis impactos antrópicos no ciclo de vida da espécie. As amostras foram coletadas mensalmente no período de março/09 a fevereiro/10 no estuário de Santos e no período de maio/08 a abril/2009 no sistema costeiro Cananéia-Iguape, utilizando rede de abalo, rede de tarrafa e cerco fixo. Em laboratório os indivíduos coletados foram medidos (mm), pesados (g) e dissecados, para a retirada das gônadas, fígado, rim e otólitos para futuras analises. Os indivíduos de Mugil curema do estuário de Santos e do sistema costeiro Cananéia-Iguape, litoral do estado de São Paulo, Brasil, foram classificadas como pertencentes ao mesmo estoque, não existindo diferenças na estrutura em tamanho, na estrutura etária e na época de desova desses indivíduos. Também foi constatado altos valores do índice de lesões histológicas e da atividade EROD no tecido do fígado e altos níveis de bioacumulação de metais (bromo, cobre, cromo, ferro e zinco) nos tecidos do fígado e rim da espécie nas duas áreas estudadas. Todas as variáveis estimadas não apresentaram diferenças significativas entre as duas áreas de estudo. / The present study has mainly aimed at understanding the population dynamic of Mugil curema from two distinct areas at coast of the state of São Paulo (Brazil), both from oceanographic and human occupation point of view. Samples were collected monthly between March/09 and February/10 of the Santos estuary and between May/08 and April/09 of the Cananéia-Iguape coastal system using gillnet, seine net and fish trap. Collected individuals were measured (mm), weighted (g) and dissected for removal of gonads, liver, kidney and otoliths for further analysis. Specimens of Mugil curema from Santos estuary and Cananéia-Iguape costal system were classified as belonging to the same stock, since the results showed no difference in structure, size, age structure and spawning season. High values of the histological lesions index and EROD activity in the liver tissue as well as increased levels of bioaccumulation of metals (bromine, copper, chromium, iron and zinc) in the liver and kidney tissues were also found. All of the estimated variables for Mugil curema were not significantly different between the two regions.
10

Digestão nitro-sulfúrica de fígado de peixe Mugil liza em forno de micro-ondas com radiação focalizada para determinar elementos de interesse ambiental por ICPMS / Fish liver (Mugil Liza) nitro-sulfuric digestion in a focused microwave system to determine elements of environmental interest by ICPMS

Monica Aparecida Ferreira de Souza Bindes Gomes Lopes 30 January 2010 (has links)
O presente estudo propõe uma metodologia para dissolução de tecidos biológicos em sistema de micro-ondas com radiação focalizada e posterior análise elementar por espectrometria de massas com plasma acoplado indutivamente (ICPMS). Foram determinados os elementos arsênio (As), cádmio (Cd), cobre (Cu), chumbo (Pb), níquel (Ni), vanádio (V) e zinco (Zn). A matriz nitro-peroxo-sulfúrica foi comparada com outra sem o ácido sulfúrico e apresentou melhor padrão de recuperação (acima de 90%) na quantificação dos elementos certificados no material de referência TORT-2. As interferências causadas pela presença do ácido sulfúrico na matriz digestora foram contornadas com o uso da célula de reação/colisão com gás hélio (He) e adição deste ácido na composição da curva de quantificação. O ganho analítico proporcionado pelo método de digestão em matriz sulfúrica, em sistema não pressurizado, baseia-se no incremento da temperatura reacional e na degradação completa da matéria orgânica. As digestões tradicionalmente realizadas para quantificação por ICPMS, compostas unicamente de ácido nítrico (HNO3) e peróxido de hidrogênio (H2O2), não apresentam a mesma eficiência na degradação da matéria orgânica em sistemas abertos. Por fim, este método foi aplicado satisfatoriamente em amostras de tecido hepático de peixe Mugil liza (tainha), comprovando sua eficiência em monitorar a bioacumulação, utilizando-se da sensibilidade da técnica multielementar de ICPMS / This study proposes a methodology for dissolution of biological tissues in microwave system with focused radiation and subsequent elemental analysis by mass spectrometry with inductively coupled plasma (ICPMS). The elements arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), nickel (Ni), vanadium (V) and zinc (Zn) were identified and quantified. The nitro-peroxo-sulfuric acid matrix was compared to another without sulfuric acid and showed better recovery (above 90%) in the quantification of elements in certified reference material TORT-2. The interferences caused by the presence of sulfuric acid in digesting matrix were bypassed by the use of ORS (octapole reaction system) with helium (He) gas and the addition of this acid in the composition of the quantification curve. The gain provided by the analytical method of digestion with sulfuric acid matrix in non-pressurized system, is based on increasing the reaction temperature and the complete degradation of organic matter. Digestions traditionally performed for quantification by ICPMS, composed only with nitric acid (HNO3) and hydrogen peroxide (H2O2), are not as efficient in the degradation of organic matter in open systems. Finally, this method was satisfactorily applied in samples of liver tissue of fish Mugil liza (mullet), proving its effectiveness in monitoring the bioaccumulation, using the sensitivity of multielemental ICPMS technique

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