Japanese eels (Anguilla japonicas) are snakelike fishes living in waters in the Asian region. In contrast to most fishes which are stenohalines that can only live in waters with a narrow range of salinity, Japanese eels are classified as euryhalines that can habitat in a broad range of salinity. As the lifecycle of Japanese eels consists of stages across fresh and seawater districts, a well-developed osmoregulation mechanism is needed to balance the intra- and extra- cellular osmolarity of the fishes throughout the seawater acclimation process. While fish gills are one of the organs that separating the ambient water and the inner body fluid of the fish, the fish gills of the Japanese eels have been studied as one of the most crucial organs for osmoregulation purposes. Yet, the osmoregulation and survival strategies of Japanese eels under hyperosmotic stress has not been fully elucidated. In chapter 2, this study has performed a transcriptome study on the ex vivo gill filament model of the Japanese eel to profile the molecular responses after a hypertonic treatment of 4 hours or 8 hours. The experiment is aimed to mimic the gill cells exposed to seawater in the seawater acclimation process of Japanese eels. A profile of differential expressed genes (DEGs) has been revealed that 577 DEGs were commonly upregulated and 711 DEGs were commonly downregulated in both 4- and 8-hours hypertonic treatment. Functional analysis and annotation have been processed with these DEGs, including Ingenuity Canonical Pathways analysis and gene ontology. These analyses have revealed that the cellular homeostasis of the gill cells has been disrupted and cell death responses has been induced by osmotic stress. The results have raises a concern that the maintenance of cellular viability and a cell death regulation mechanism are needed for the fishes to survive in the early stage of seawater acclimation. In chapter 3, this chapter demonstrated that gill cells in Japanese eels are susceptible to apoptosis when they are exposed to hyperosmotic treatments in both in vitro gill cell and the ex vivo gill filament model. To maintain the viability of the gills cells, two inhibitors of apoptosis, XIAP, and survivin, were seen to be expressed in gills cells. The expression of XIAP and survivin were upregulated by dexamethasone, which is an agonist mimicking the effect of cortisol on fishes in seawater acclimation. Meanwhile, the expression levels of the apoptosis executor, caspase 3, were downregulated. These data suggested that with the regulation of cortisol express in the fishes, XIAP and survivin are effective apoptosis regulators in the gill cells of Japanese eels. The study has demonstrated the molecular responses of the gills of Japanese eels exposed to hyperosmotic stress at the transcriptional level and post-translational level by using transcriptome studies and protein study respectively. The study has paved cell death regulation to be another the key field to study in understanding the ability of salinity tolerance in euryhalines.

No description available.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2002. / Includes bibliographical references (leaves 113-116).

D.Phil. / The results of this investigation suggested that fish hatcheries may cause a deterioration in water quality of thereceiving stream. With regards trout hatcheries, two sources of pollution were distinguished. These were tenned normal or continuous hatchery effluent and secondly dam cleaning effluent. The former effluent was of little pollution consequence. The bacterial analyses indicated that faecal bacterial concentrations were largely determined by the concentration of these bacteria already present in the influent water. However, hatcheries can result in an increase in faecal bacterial concentrations downstream. Biological growth potential investigations suggested that both normal effluents and dam cleaning effluents were only slightly enriched in comparison with the influent conditions. Metabolizable nutrient addition to the effluent water was considered to be of little importance. Although the hatchery effluent from trout hatcheries may result in marked disturbances in the aquatic macro-invertebrate fauna, the organism community structures indicated that severe organic pollution was not occurring. The communities of the macro-invertebrates had become almost normalized within 300 m of the hatchery outfalls'. The water chemistry analyses confirmed the biological findings. The suspended material from both trout and carp hatcheries was the most important contributor to pollution. Recommendations included the use of the existing chemical and physical standards of the Water Act of 1956, however that these should be supplement~d by other biological parameters. A distance of 1 km should exist between a trout hatchery and a farm boundary unless effluent treatment is undertaken. Carp dam effluent may have to be treated depending on the water quality of the receiving stream.

published_or_final_version / abstract / Environmental Management / Master / Master of Science in Environmental Management

Thesis (MPhil)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Emerging global trends towards sustainable development have placed emphasis on the need to create sustainable food value chains. Many food value chains are becoming weakened through their reliance on eco-systems that are deteriorating. Furthermore, while food systems are under threat, global food consumption is on the rise. The conundrum seems inescapable. Humanity’s food supply methods have moved on from hunter-gatherer characteristics apart from the exception of the fishing industry. The current generation may be the last to witness the wide-spread practice of fishing. Aquaculture, and in particular fish-farming, has begun to show much potential as a method of producing sustainable sources of protein. Whether this can be utilized in the South African context is a challenge that needs to be verified. This research, presented as two articles, explores the potential for the development of the fish-farming sector in South Africa, and recommends suitable species. Although there is some literature on how fish-farming may have a place in South Africa’s sustainability quest, it is scarce. This research aims to enhance the literature base on fish-farming in South Africa, as well as provide further evidence on what the true potential is for fish-farming in South Africa. This was done through a series of primary and secondary data collection methods that allow for a thorough analysis of fish-farming in South Africa and the species involved. The analysis revealed that the fish-farming sector and the cultivatable species in South Africa are met with an array of opportunities and challenges. Overcoming these challenges will open the doors to exploit the opportunities available. / AFRIKAANS OPSOMMING: Opkomende globale tendense weerspieël dat dit noodsaaklik is dat klem gelê moet word op volhoubare ontwikkeling en dat dit van uitterste belang is om volhoubare voedsel waardekettings te skep. Verskeie voedsel waardekettings raak verswak deur hul afhanklikheid van eko-stelsels wat vernietig word. Verder, terwyl voedsel stelsels bedreig word, is globale verbruik van voedsel besig om te verhoog. Dié raaisel lyk onvermydelik. Mensdom se huidige voedselvoorraad metodes het aansienlik ontwikkel van dié van die jagter-versamelaars, met die uitsondering van die visbedryf. Die huidige generasie mag die laaste wees, wat die wyd verspreide praktyk van visvang beoefen, om daarvan te getuig. Akwakultuur, in besonder vis-boerdery, het begin om potensiaal te wys as 'n volhoubare bron in die vervaardiging van proteïen. Of dit in die Suid-Afrikaanse konteks gebruik kan word, is 'n uitdaging wat geverifieer moet word. Hierdie navorsing, wat aangebied word as twee tydskrifartikels, ondersoek die potensiaal vir die ontwikkeling van vis-boerdery in Suid-Afrika, en beveel ook gepaste spesies aan. Alhoewel daar sommige artikels is oor hoe vis-boerdery kan in pas in Suid-Afrika se soeke na volhoubaarheid, is dit skaars te vinde. Die navorsing beoog om die literatuur basis van vis-boerdery in Suid-Afrika op te skerp, en ter selfde tyd verdere bewys te gee oor die ware potensiaal van vis-boerdery in Suid-Afrika. Dit was gedoen deur 'n reeks van primêre en sekondêre data-insameling metodes wat voorsiening maak vir 'n deeglike ontleding van visboerdery in Suid -Afrika en die spesies betrokke. Die ontleding het getoon dat die vis-boerdery bedryf en die aankweek spesies in Suid-Afrika verskeie geleenthede en uitdagings in die gesig staar. Oorwinning van hierdie uitdagings sal dit moontlik maak om die beskikbare geleenthede te ontgin.

Made available in DSpace on 2014-06-11T19:29:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-14Bitstream added on 2014-06-13T20:38:38Z : No. of bitstreams: 1 cicigliano_gd_me_ilha.pdf: 3848285 bytes, checksum: 4fa431ea33f04e77357210cfb9c87e80 (MD5) / O presente projeto teve como objetivo avaliar a qualidade da água em função do efluente gerado por uma unidade de piscicultura localizado na Bacia Hidrográfica do Rio São José dos Dourados, no Município de Santa Fé do Sul, SP. As análises foram realizadas a cada quatro semanas, por um período de doze meses, realizado em locais previamente determinados sendo repetidas á cada coleta. As investigações foram realizadas dentro de uma abordagem de análise ambiental ampla e de uma perspectiva de desenvolvimento sustentável. O estudo de cada um dos parâmetros de qualidade da água foi realizado por meio da obtenção de dados no próprio local e de análises laboratoriais. As coletas foram realizadas em pontos definidos previamente (03 pontos) de modo servir como indicadores das condições ambientais na micro bacia e de suas possíveis alterações em função dos efluentes gerados pelos peixes cultivados no local. Desta forma, procurou-se investigar a influência da atividade de piscicultura em termos de efluentes gerados para a deterioração dos recursos hídricos do local. Foram analisadas possíveis alterações nas características físicas, químicas e biológicas da água, relacionadas ao uso da água na micro-bacia. Os Resultados dos ensaios obtidos confrontados com os padrões da resolucão CONAMA n° 357/05, águas doces classe 2, bem como os índices de qualidade de água IQA. De modo geral foi observado que as águas do Córrego Ponte Pensa não apresentarem índices, ótimo. Para os índices mínimos, observaram-se duas classificações como boa, e uma classificação como aceitável. Para os índices máximos observaram-se três classificações como aceitável. Espera-se com os resultados obtidos fornecer subsídios que possam contribuir para o desenvolvimento sócio-econômico local associado à conservação ambiental / The present project had as objective to evaluate the quality of the water in function of the effluent one generated by a unit of fish culture located in the Hidrográfica Basin of the River São José dos Dourados, in the City Santa Fé do Sul, SP. The analyses had been carried through to each four weeks, for a period of twelve months, carried through in places previously determined being repeated to each collection. The inquiries had been carried through inside of a boarding of ample analysis ambient and of a perspective of sustainable development. The study of each one of the parameters of quality of the water it was carried through by means of the attainment of data in the proper place and laboratory analyses. The collections had been carried through in definite points previously (03 points) in way to serve as indicating of the ambient conditions in the micron basin and of its possible alterations in function of the effluent ones generated by the fish cultivated in the place. In such a way it was looked to investigate the influence of the activity of fish culture in generated terms of effluent for the deterioration of the water resources of the place. Had been analyzed possible alterations in the physical, chemical and biological characteristics of the water, related to the use of the water in the micron-basin. The Results of the assays gotten collated with the standards of resolution CONAMA n º 357/05, waters candies classroom 2, as well as the indices of quality of water IQA In general way it was observed that the waters of the stream Ponte Pensa think not to present indices, excellent. For the minimum indices, two classifications had been observed as good, and a classification as acceptable. One expects with the gotten results to supply subsidies that can contribute for the associated local partner-economic development to the ambient conservation

Orientador: Sérgio Luís de Carvalho / Banca: Alexandre Ninhaus Silveira / Banca: Ricardo Pereira Ribeiro / Resumo: O presente projeto teve como objetivo avaliar a qualidade da água em função do efluente gerado por uma unidade de piscicultura localizado na Bacia Hidrográfica do Rio São José dos Dourados, no Município de Santa Fé do Sul, SP. As análises foram realizadas a cada quatro semanas, por um período de doze meses, realizado em locais previamente determinados sendo repetidas á cada coleta. As investigações foram realizadas dentro de uma abordagem de análise ambiental ampla e de uma perspectiva de desenvolvimento sustentável. O estudo de cada um dos parâmetros de qualidade da água foi realizado por meio da obtenção de dados no próprio local e de análises laboratoriais. As coletas foram realizadas em pontos definidos previamente (03 pontos) de modo servir como indicadores das condições ambientais na micro bacia e de suas possíveis alterações em função dos efluentes gerados pelos peixes cultivados no local. Desta forma, procurou-se investigar a influência da atividade de piscicultura em termos de efluentes gerados para a deterioração dos recursos hídricos do local. Foram analisadas possíveis alterações nas características físicas, químicas e biológicas da água, relacionadas ao uso da água na micro-bacia. Os Resultados dos ensaios obtidos confrontados com os padrões da resolucão CONAMA n° 357/05, águas doces classe 2, bem como os índices de qualidade de água IQA. De modo geral foi observado que as águas do Córrego Ponte Pensa não apresentarem índices, ótimo. Para os índices mínimos, observaram-se duas classificações como boa, e uma classificação como aceitável. Para os índices máximos observaram-se três classificações como aceitável. Espera-se com os resultados obtidos fornecer subsídios que possam contribuir para o desenvolvimento sócio-econômico local associado à conservação ambiental / Abstract: The present project had as objective to evaluate the quality of the water in function of the effluent one generated by a unit of fish culture located in the Hidrográfica Basin of the River São José dos Dourados, in the City Santa Fé do Sul, SP. The analyses had been carried through to each four weeks, for a period of twelve months, carried through in places previously determined being repeated to each collection. The inquiries had been carried through inside of a boarding of ample analysis ambient and of a perspective of sustainable development. The study of each one of the parameters of quality of the water it was carried through by means of the attainment of data in the proper place and laboratory analyses. The collections had been carried through in definite points previously (03 points) in way to serve as indicating of the ambient conditions in the micron basin and of its possible alterations in function of the effluent ones generated by the fish cultivated in the place. In such a way it was looked to investigate the influence of the activity of fish culture in generated terms of effluent for the deterioration of the water resources of the place. Had been analyzed possible alterations in the physical, chemical and biological characteristics of the water, related to the use of the water in the micron-basin. The Results of the assays gotten collated with the standards of resolution CONAMA n º 357/05, waters candies classroom 2, as well as the indices of quality of water IQA In general way it was observed that the waters of the stream Ponte Pensa think not to present indices, excellent. For the minimum indices, two classifications had been observed as good, and a classification as acceptable. One expects with the gotten results to supply subsidies that can contribute for the associated local partner-economic development to the ambient conservation / Mestre

published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

published_or_final_version / Real Estate and Construction / Doctoral / Doctor of Philosophy