The humanity, until very little time behind, it thought to be the ocean and the water inexhaustible goods and with conditions of provisioning unlimitedly the necessary animal protein to the life. With the growth of the population and the growing demand for food was possible to observe that the alone nature would not be capable to supply those needs. After the decade of 1970, due to overfishing of some important species a new found alternative went commercially to aquaculture. One of the objectives of this work is to answer the aquaculture, as technology of production of victuals of aquatic origin, it can be a sustainable alternative for the solution of the problem mentioned above, using for that a study of case of the project of fish farming Curupati-Peixe installed in the dam CastanhÃo, Jaguaribara-CearÃ. For that it was used as methodology indexes and sustainability degree obtained by three scopes- economicsocial, technological and environmental indicators, everybody these defined and measured for the aquaculture. The method of systems was used as form of capturing the maximum of interrelations among the sub-systems that it composes the sustainable aquaculture. It was observed that the fish farming is shown potentially maintainable, obtaining a medium sustainability (0,603) for the project Curupati-Peixe, being the index of Social Capital (ICS), with value of 0,797, the one that more contributed and the Technological Index (IT), just 0,407, which fewer contributes to that sustainability level. / O ser humano, atà bem pouco tempo atrÃs, pensava ser o oceano e a Ãgua bens inesgotÃveis e com condiÃÃes de abastecer ilimitadamente a proteÃna animal necessÃria à vida. Com o crescimento populacional e a crescente demanda por alimento foi possÃvel observar que a natureza sozinha nÃo seria capaz de suprir essas necessidades. ApÃs a dÃcada de 1970, devido a sobrepesca de algumas espÃcies importantes comercialmente uma nova alternativa encontrada foi a aqÃicultura. Um dos objetivos deste trabalho à responder se a aqÃicultura, como tecnologia de produÃÃo de alimentos de origem aquÃtica, pode ser uma alternativa sustentÃvel para a soluÃÃo do problema citado acima, usando para isso um estudo de caso do projeto de piscicultura Curupati-Peixe instalado no aÃude CastanhÃo, Jaguaribara-CearÃ. Para isso usou-se como metodologia Ãndices e grau de sustentabilidade obtidos por trÃs escopos â indicadores econÃmico-sociais, tecnolÃgicos e ambientais, todos estes definidos e mensurados para a aqÃicultura. Utilizou-se o mÃtodo sistÃmico como forma de captar o mÃximo de interrelaÃÃes entre os subsistemas que compÃe a aqÃicultura sustentÃvel. Observou-se que o projeto de piscicultura Curupati-Peixe mostra-se potencialmente sustentÃvel, obtendo uma mÃdia sustentabilidade (0,603) para o projeto Curupati-Peixe, sendo o Ãndice de Capital Social (ICS), com valor de 0,797, o que mais contribuiu e o Ãndice TecnolÃgico (IT), apenas 0,407, o que menos contribui para esse nÃvel de sustentabilidade.

COELHO, Anderson Alan da Cruz. Cultivo integrado de juvenis de Tilápia do Nilo (Oreochromis niloticus) com a microalga Spirulina platensis: uma alternativa para tratamento de efluente aquícola. 2012. 43 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T11:33:51Z No. of bitstreams: 1 2012_dis_aaccoelho.pdf: 607546 bytes, checksum: 12fe04486dfe8ee87995d9e313b1cb2c (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T11:46:06Z (GMT) No. of bitstreams: 1 2012_dis_aaccoelho.pdf: 607546 bytes, checksum: 12fe04486dfe8ee87995d9e313b1cb2c (MD5) / Made available in DSpace on 2016-07-11T11:46:06Z (GMT). No. of bitstreams: 1 2012_dis_aaccoelho.pdf: 607546 bytes, checksum: 12fe04486dfe8ee87995d9e313b1cb2c (MD5) Previous issue date: 2012 / The environmental potential impacts from intensive aquaculture have increased public concern about the sustainability of the activity itself. The present work aimed to evaluate the zootécincos parameters of Nile tilapia , water quality, algal biomass production and rate of nitrogen removal compounds by Spirulina platensis realize an integrated cultivation of Nile tilapia (Oreocrhomis niloticus) with Spirulina platensis in a closed system of water circulation. The experiment took place at the Biotechnology Aquaculture Applied Center (CEBIAQUA) of The Fishing Engineering Department of the Federal University of Ceará. Tilapias culture was conducted in three treatments with four replicates at densities of 010, 0,15 and 0,20 juveniles L-1. The tilapias were fed ad libitum with a commercial ration (0,8 mm) containing 55% crude protein (CP), administered daily at 9, 13 and 17 h. For Spirulina platensis culture, initially, the inoculum was cultivated in an alternative chemical medium and later adapted to the Nile tilapia effluent and inoculated into 12 polyethylene basins. Throughout the experiment, the water of fishes boxes and of the respective microalgae basins was reused in the closed recirculation system between the two cultures, with only replacement of water due to evaporation. After the full development of S. platensis in the basins, the microalgae was collected using a 60 µm screen. The pH, temperature, dissolved oxygen, and levels of N-ammonia, N-nitrate and N-nitrite were also monitored during all the experimental period. The results showed that the most efficient stocking density was 0,10 L-1, because despite having the same final biomass of the other treatments it presented the lowest feed conversion ratio. The microalgae S. platensis was easily adapted and developed very well in the Nile tilapia’s effluent, regardless of fishes stocking density. With respect to water quality, it was evident that the cultures integration maintained the levels of N-ammonia (0,26 ± 0,03 mg L-1), N-nitrates (2,55 ± 0,71 mg L-1) and N- nitrites (0,19 ± 0,01 mg L-1) within acceptable values for the Nile tilapia culture. / Os potenciais impactos ambientais provenientes da aquicultura intensiva têm aumentado a preocupação da sociedade quanto à sustentabilidade da própria atividade. Com o presente trabalho teve como objetivo avaliar, os parâmetros zootécincos das tilápias do Nilo, qualidade de água, produção de biomassa algal e taxa de remoção dos compostos nitrogenados pela microalga Spirulina platensis em um cultivo integrado da tilápia do Nilo (Oreocrhomis niloticus) com a microalga S. platensis em um sistema fechado de circulação de água. O experimento foi realizado no Centro de Biotecnologia Aplicada a Aquicultura (CEBIAQUA) do Departamento de Engenharia de Pesca da Universidade Federal do Ceará. O cultivo das tilápias foi inteiramente casualizado e realizado em três tratamentos com quatro repetições nas densidades de 0,1; 0,15 e 0,20 juvenis L-1. As tilápias foram alimentadas ad libitum com ração comercial (0.8 mm), contendo 55% de proteína bruta (PB), fornecida às 9, 13 e 17 h, sete dias por semana. Para o cultivo de Spirulina platensis, inicialmente, o inóculo foi cultivado em meio químico alternativo e posteriormente adaptado ao efluente de tilápia do Nilo e inoculado em 12 bacias de polietileno. Durante todo o experimento, a água das caixas dos peixes e das respectivas bacias das microalgas foi reutilizada no sistema de recirculação fechado entre as duas culturas, havendo apenas reposição de água por conta da evaporação. Após o completo desenvolvimento da S. platensis nas bacias, a coleta da microoalga foi realizada através de filtragem da água em telas de 60 µm. Foram ainda monitorados o pH, temperatura, oxigênio dissolvido, bem como determinados os níveis de N-amônia, N-nitrato e N-nitrito durante o período experimental. Os resultados mostraram que a densidade de estocagem mais eficiente para o cultivo das tilápias foi 0,10 juvenis L-1, pois apesar de ter resultado na mesma biomassa final dos demais tratamentos, foi a que apresentou a menor taxa de conversão alimentar. A microalga S. platensis se adaptou facilmente e se desenvolveu muito bem no efluente das tilápias do Nilo, independente da densidade de estocagem dos peixes. Com relação à qualidade de água, foi evidenciado que a integração das culturas manteve os níveis de N-amônia (0,26 ± 0,03 mg L-1), N-nitrato (2,55 ± 0,71) e N-nitrito (0,19 ± 0,01) dentro dos valores aceitáveis para o cultivo da tilápia do Nilo.

MATIAS, João Felipe Nogueira. Análise da Sustentabilidade da Aquicultura em Águas de Domínio da União, no Parques Aquícolas do Reservatório do Castanhão, Estado do Ceará: Estudo de Caso. 2012. 126 f . : Tese (doutorado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-26T15:20:59Z No. of bitstreams: 1 2012_tese_jfnmatias.pdf: 3782406 bytes, checksum: 45522708ae24dcb10a808bc69a58a288 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-26T15:21:15Z (GMT) No. of bitstreams: 1 2012_tese_jfnmatias.pdf: 3782406 bytes, checksum: 45522708ae24dcb10a808bc69a58a288 (MD5) / Made available in DSpace on 2016-07-26T15:21:15Z (GMT). No. of bitstreams: 1 2012_tese_jfnmatias.pdf: 3782406 bytes, checksum: 45522708ae24dcb10a808bc69a58a288 (MD5) Previous issue date: 2012 / The fisheries activity already reached or exceeded the limits of sustainable maximum capture in the majority of fisheries in the world. At the same time, the consumption of fish products in world-wide level comes more increasing each time. The problem is how to increase the fish production without increasing the fisheries efforts. The solution can be aquaculture, however this activity must be carried through with social insertion, environmental responsibility, economic viability and with a good governance. In Brazil, aquaculture have been a very good developing, specially in the water reservoirs of Union domain. This work had analyzed the sustentability of aquaculture in these waters using the aquícolas parks of the reservoir of Castanhão, in the state of Ceará as a case study. For this, it was used an elaboration of a socialeconomical profile of two groups of assignees (beneficiary and controll), what it demonstrated the positive influence of the fishculture in this profile. And it was elaborated subíndexes that involves social, environmental, institucional (governance) and economic dimensions of sustentability; that had allowed the construction of the index of sustainable development of the aquaculture. It was verified that this aquaculture system in question got a result fit as of media sustentability. / O extrativismo pesqueiro já alcançou ou até já ultrapassou os limites de captura máxima sustentável na maioria das pescarias no mundo. Ao mesmo tempo, o consumo de pescado per capta em nível mundial vem aumentando cada vez mais. O problema é como aumentar a produção de pescado sem aumentar os esforços de pesca. A solução pode ser a aqüicultura, porém esta atividade deve ser realizada com inserção social, responsabilidade ambiental, viabilidade econômica e com uma boa governança. No Brasil, a aqüicultura vem se desenvolvendo bastante, especialmente nos reservatórios de águas de domínio da União. Este trabalho se propôs a analisar a sustentabilidade da aqüicultura em águas de domínio da União utilizando os parques aquícolas do reservatório do Castanhão, no estado do Ceará como estudo de caso. Para isto, utilizou-se a elaboração de um perfil socioeconômico de dois grupos de cessionários (beneficiário e controle), o que demonstrou a influência positiva da piscicultura neste perfil. E elaborou-se subíndices que englobaram as dimensões sociais, ambientais, institucionais (governança) e econômicas de sustentabilidade; que por sua vez permitiram a construção do índice de desenvolvimento sustentável da aquicultura. Verificou-se que o sistema aquícola em questão obteve um resultado enquadrado como de média sustentabilidade.

NASCIMENTO, Sandra Carla Olveira do. Avaliação da sustentabilidade do projeto de Piscicultura Curupati-Peixe no açude Castanhão, Jaguaribara-CE. 2007. 127 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Programa Regional de Pós-Graduação em Desenvolvimento e Meio Ambiente - PRODEMA / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-09T12:52:38Z No. of bitstreams: 1 2007_dis_sconascimento.pdf: 1795959 bytes, checksum: f35aa296de798cde8808bb84c47d7633 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-09T12:52:53Z (GMT) No. of bitstreams: 1 2007_dis_sconascimento.pdf: 1795959 bytes, checksum: f35aa296de798cde8808bb84c47d7633 (MD5) / Made available in DSpace on 2016-05-09T12:52:53Z (GMT). No. of bitstreams: 1 2007_dis_sconascimento.pdf: 1795959 bytes, checksum: f35aa296de798cde8808bb84c47d7633 (MD5) Previous issue date: 2007 / The humanity, until very little time behind, it thought to be the ocean and the water inexhaustible goods and with conditions of provisioning unlimitedly the necessary animal protein to the life. With the growth of the population and the growing demand for food was possible to observe that the alone nature would not be capable to supply those needs. After the decade of 1970, due to overfishing of some important species a new found alternative went commercially to aquaculture. One of the objectives of this work is to answer the aquaculture, as technology of production of victuals of aquatic origin, it can be a sustainable alternative for the solution of the problem mentioned above, using for that a study of case of the project of fish farming Curupati-Peixe installed in the dam Castanhão, Jaguaribara-Ceará. For that it was used as methodology indexes and sustainability degree obtained by three scopes- economicsocial, technological and environmental indicators, everybody these defined and measured for the aquaculture. The method of systems was used as form of capturing the maximum of interrelations among the sub-systems that it composes the sustainable aquaculture. It was observed that the fish farming is shown potentially maintainable, obtaining a medium sustainability (0,603) for the project Curupati-Peixe, being the index of Social Capital (ICS), with value of 0,797, the one that more contributed and the Technological Index (IT), just 0,407, which fewer contributes to that sustainability level. / O ser humano, até bem pouco tempo atrás, pensava ser o oceano e a água bens inesgotáveis e com condições de abastecer ilimitadamente a proteína animal necessária à vida. Com o crescimento populacional e a crescente demanda por alimento foi possível observar que a natureza sozinha não seria capaz de suprir essas necessidades. Após a década de 1970, devido a sobrepesca de algumas espécies importantes comercialmente uma nova alternativa encontrada foi a aqüicultura. Um dos objetivos deste trabalho é responder se a aqüicultura, como tecnologia de produção de alimentos de origem aquática, pode ser uma alternativa sustentável para a solução do problema citado acima, usando para isso um estudo de caso do projeto de piscicultura Curupati-Peixe instalado no açude Castanhão, Jaguaribara-Ceará. Para isso usou-se como metodologia índices e grau de sustentabilidade obtidos por três escopos – indicadores econômico-sociais, tecnológicos e ambientais, todos estes definidos e mensurados para a aqüicultura. Utilizou-se o método sistêmico como forma de captar o máximo de interrelações entre os subsistemas que compõe a aqüicultura sustentável. Observou-se que o projeto de piscicultura Curupati-Peixe mostra-se potencialmente sustentável, obtendo uma média sustentabilidade (0,603) para o projeto Curupati-Peixe, sendo o Índice de Capital Social (ICS), com valor de 0,797, o que mais contribuiu e o Índice Tecnológico (IT), apenas 0,407, o que menos contribui para esse nível de sustentabilidade.

This thesis is intended to improve the understanding of China’s evolving export-oriented farmed seafood systems, and in particularly, shrimp and tilapia farming value chains in Southern China. An integrated, systems thinking and interdisciplinary approach in which both top–down and bottom–up approaches were combined. The research moved from system reviews, to field surveys and workshops, and then to improving sustainability by Action Research (AR), in order to form a holistic understanding of sustainability at both national and local scales. In the new millennium, the aquaculture sector has matured, and many factors now slow the growth rate of Chinese aquaculture production, such as increasing culture of high-value species and an emerging trend of extensification. There are been some strategy shifts in the aquaculture industry such as changing from a high production to high profit orientation and from causing environmental damage to ecological remediation. A key conclusion is that high growth rates, regularly used in policy dialogues, are misleading indicators and do not reflect, realistic or sustainable, growth profiles. Although overall Chinese aquaculture production is likely to further increase to meet an increasing and changing market demand, growth rates will decrease further. China already is and will continue to be a fisheries products net importer, however, if fishmeal excluded China will remain as a seafood net exporter. The status and development of four internationally-traded farmed seafood, tilapia, penaeid shrimp, macrobrachium prawns and striped catfish in China were reviewed. China is the largest producer of tilapia, penaeid shrimp and macrobrachium prawns, and striped catfish is not produced in significant quantities due to climate limitations. Meanwhile, China is the largest exporter of tilapia, the second largest exporter in the volume and third in value of shrimp in the world, while macrobrachium prawns mainly support domestic markets. Tilapia and penaeid shrimp were selected for further research. An analysis of tilapia and shrimp farm scale indicators and their relationship to farming system and market orientation, farm intensification and performance was made. Farm area, both land and water area, labour, including paid and unpaid were effective indicators to distinguish farm scale. Small-scale farms had higher land productivity in production terms but no difference in value output term, and they had much lower labour productivity than medium and large-scale farms. Farming systems were also correlated with land and labour productivities. Market orientation was closely linked to farm scale as most farms with an export orientation required registration with CIQ (China Entry-Exit Inspection and Quarantine) and were mainly large-scale. An assessment of local stakeholder sustainability perspectives along value chains revealed that more than 80% shrimp and tilapia farmers didn’t want their children to continue basing their living on aquaculture; because they considered it hard work, high risk and poorly remunerated. Farming was comparative stable with few changes in the five years prior to the survey. Major sustainability factors identified by stakeholders included input costs, profit, water availability & quality and the weather, most of which were outside their control. The measurement of these sustainability factors was firstly proposed by stakeholders and then developed to a set of sustainability indicators (SIs). Life cycle assessment (LCA) was used as evaluate the environmental performance of tilapia, pig and integrated tilapia-pig farming systems in China. Pig farming had higher environment impacts based on most impact categories than tilapia, and integrated farming systems. Sensitivity analysis showed that improvements of 5% and 10% higher feed efficiency, reduction of fishmeal in feed to 1% level and use of EU electricity could significant reduce overall environmental impacts. An action research (AR) approach was used to assess the practice of farm record keeping with farmers which were found to be generally low and a major constraint to improving product traceability increasingly demanded by consumers. Large scale and CIQ farms were more likely to keep records and for them to be detailed and analysed to inform improved management. Farmers’ motivation, ability and capability and background had significant correlation with record keeping practice. Two major dilemmas were identified by the analysis. Easy-to-use farm record-keeping system more suitable for less formally educated farmers was a clear requirement but useful storage and analysis of farm data capacity requires sophisticated management tools such as a computer system. Another dilemma is the need for coercion by regulatory authorities or encouragement through provision of education and training in increasing on-farm record-keeping to a level required for international trade and, increasingly, domestic markets. “Precision aquaculture”, value chain integrated solution, and further social-economic reforms were discussed. Finally, sustainable intensification, diversification, and extensification were proposed as strategies for China to meet the challenges of globalization and the growing demands of export and domestic value chains. In order to enhance sustainability of the sector and provide opportunities for small-scale farmers, the current status and changes of the Chinese social, economic context, food safety and environments issues were discussed. Farmers’ organizations, future consolidation, and land reforms were identified as key to the required changes of farmed seafood value chains.

Earth’s population is expected to reach 9 billion by 2050. Ensuring food security for the growing world population is one of today’s society’s major challenges and responsibilities. Aquatic products have the potential to contribute significantly in the growing population’s dietary requirements. Since increasing the pressure on most natural fish stocks is now widely agreed not to be an option, the aquaculture sector needs to grow. The challenge is to increase aquaculture production without depleting natural resources or damaging the environment but also in a financially sustainable way. Integrated Multitrophic Aquaculture (IMTA) is one method of sustainable aquatic production. Integrating bioremediatory organisms that extract particulate organic matter or dissolved inorganic nutrients with monocultures of fed species has the potential of reducing the particulate and soluble waste loads from effluents, whilst producing a low-input protein source that may also increase the farm income. IMTA is a viable solution for mitigating the environmental impact of waste released from fish farms. The fish waste is exploited as a food source for lower trophic, extractive organisms giving an added value to the investment in feed. Studies up to now have shown that under experimental conditions as well as in small-scale commercial studies, various filter-feeding, deposit-feeding and grazing species can ingest fish waste particles. The aim now is to achieve IMTA optimization, where extractive organisms can ingest most of the finfish waste food and excretions. Any such design is likely to be complex incorporating a multidisciplinary approach, and therefore to date a reason why most studies have failed to prove the environmental and economic benefits of IMTA. Consequently, the aim of this study is to develop ways of selecting an ideal combination of species for a specific locality, manage the cultures in a way that ensures the maximum nutrient recycling feasible per unit of area; and ensure high growth rate of the extractive organisms while being financially beneficial. The approach taken was a combination of investigative literature reviews, computer modelling work and small-scale growth trials to determine the relative growth of extractive organisms fed fishfeed and waste, followed by the development of a systems-based model of interaction and growth efficiency for combinations of organisms within an IMTA system. This study starts by investigating, with small-scale laboratory experiments, the potential of two organic extractive species, the lugworm, Arenicola marina and the sea urchin, Psammechinus miliaris, as organic extractive components of IMTA systems. Their ability to consume and assimilate salmon faeces was evaluated as well as their remediation efficiency. This was done by comparing the carbon, nitrogen and phosphorus content of the pellet-faeces mixture to that of the sea urchin faeces and sea urchin gonad content. Their growth, gonadosomatic index (GSI) (for the sea urchins), tissue carbon, nitrogen and phosphorous content were compared between seaweed diets and a diet consisting of a mixture of salmon faeces and feed pellets. The results showed statistically significant gonad carbon content for the sea urchins fed with faeces. Similarly, statistically significant higher phosphorous content was found in the tissues of the lugworms fed with the mixture of salmon faeces and pellets than in the lugworms of the other two groups. The subsequent and main phase of this study was the development of a model for optimising IMTA performance. The modelling process included model development, run, optimization and risk assessment. The IMTA model developed consisted of Atlantic salmon Salmo salar, the sea urchin Paracentrotus lividus and the macroalgae Ulva sp. It simulates the growth as well as the uptake and release of nitrogen by these organisms under environmental conditions of a hypothetical site on the west coast of Scotland. The aim of the model was to maximize the potential of IMTA in terms of productivity and to reduce the amount of nutrients that are released in the environment, and thus to contribute towards a more sustainable and productive form of aquaculture. The IMTA model developed can be re-parameterised to simulate the growth and nutrient uptake of different species and the growth and nutrient uptake under different environmental conditions. This capacity of the model was used in order to do a comparative study of the nitrogen bioremediation potential of three different invertebrate species, cultivated as part of an IMTA. These species were the lugworm (Arenicola marina), the blue mussel (Mytilus edulis) and the purple sea urchin (Paracentrotus lividus). The results of this comparative study showed that weight for weight, M. edulis is more efficient in removing POM than P. lividus that is in turn better than A. marina with regard to the amount of nitrogen they can assimilate. But in terms of cultivation area required for the production of the same total biomass, P. lividus was better at removing POM followed by M. edulis and then by A. marina.

In recent times, diminishing freshwater resources, due to the rapidly increasing drain of urban, industrial and agricultural activities in combination with the impact of climate change, has led to an urgent need to manage marine and brackish water environments more efficiently. Therefore the diversification of aquacultural practices, either by the introduction of new candidate species or by the adaptation of culture methods for existing species, is vital at a time when innovation and adaptability of the aquaculture industry is fundamental in order to maintain its sustainability. The Nile tilapia (Oreochromis niloticus, Linnaeus, 1758), which has now been spread well beyond its natural range, dominates tilapia aquaculture because of its adaptability and fast growth rate. Although not considered to be amongst the most salt tolerant of the cultured tilapia species, the Nile tilapia still offers considerable potential for culture in low-salinity water. An increase in knowledge of the limits and basis of salinity tolerance of Nile tilapia during the sensitive early life stages and the ability to predict responses of critical life-history stages to environmental change could prove invaluable in improving larval rearing techniques and extend the scope of this globally important fish species. The capability of early life stages of the Nile tilapia to withstand variations in salinity is due to their ability to osmoregulate, therefore the ontogeny of osmoregulation in the Nile tilapia was studied from spawning to yolk-sac absorption after exposure to different experimental conditions ranging from freshwater to 25 ppt. Eggs were able to withstand elevated rearing salinities up to 20 ppt, but transfer to 25 ppt induced 100% mortality by 48 h post-fertilisation. At all stages embryos and larvae hyper-regulated at lower salinities and hypo-regulated at higher salinities, relative to the salinity of the external media. Osmoregulatory capacity increased during development and from 2 days post-hatch onwards remained constant until yolk-sac absorption. Adjustments to larval osmolality, following abrupt transfer from freshwater to experimental salinities (12.5 and 20 ppt), appeared to follow a pattern of crisis and regulation, with whole-body osmolality for larvae stabilising at c. 48 h post-transfer for all treatments, regardless of age at time of transfer. Age at transfer to experimental salinities (7.5 – 20 ppt) had a significant positive effect on larval ability to osmoregulate; larvae transferred at 8 dph maintained a more constant range of whole body osmolality over the experimental salinities tested than larvae at hatch. Concomitantly, survival following transfer to experimental salinities increased with age. There was a significant effect (GLM; p < 0.05) of salinity of incubation and rearing media on the incidence of gross larval malformation that was seen to decline over the developmental period studied. It is well established that salinity exerts a strong influence on development and growth in early life stages of fishes therefore the effects of varying low salinities (0 - 25 ppt) on hatchability, survival, growth and energetic parameters were examined in the Nile tilapia during early life stages. Salinity up to 20 ppt was tolerable, although reduced hatching rates at 15 and 20 ppt suggest that these salinites may be less than optimal. Optimum timing of transfer of eggs from freshwater to elevated salinities was 3-4 h post-fertilisation, following manual stripping and fertilisation of eggs, however increasing incubation salinity lengthened the time taken to hatch. Salinity was related to dry body weight, with larvae in salinities greater than 15 ppt displaying, at hatch, a significantly (GLM: p < 0.05) lower body weight but containing greater yolk reserves than those in freshwater or lower salinities. Survival at yolk-sac absorption displayed a significant (GLM; p < 0.05) inverse relationship with increasing salinity and mortalities were particularly heavy in the higher salinities of 15, 20 and 25 ppt. Mortalities occurred primarily during early yolk-sac development yet stabilised from 5 dph onwards. Salinity had a negative effect on yolk absorption efficiency (YAE). Salinity-related differences in oxygen consumption rates were not detectable until 3 days post-hatch; oxygen consumption rates of larvae in freshwater between days 3 – 6 post-hatch were always significantly higher (GLM p < 0.05) than those in 7.5, 15, 20 and 25 ppt, however, on day 9 post-hatch this pattern was reversed and freshwater larvae had a significantly lower QO2 than those in elevated salinities. Salinity had a significant inverse effect on larval standard length, with elevated salinities producing shorter larvae from hatch until 6 dph, after which time there was no significant differences between treatments. Salinity had a significant effect on whole larval dry weight, with heavier larvae in elevated salinities throughout the yolk-sac period (GLM; p < 0.05). The ability of the Nile tilapia to withstand elevated salinity during early life stages is due to morphological and ultrastructural modifications of extrabranchial mitochondria-rich cells (MRCs) that confer an osmoregulatory capacity before the development of the adult osmoregulatory system. A clearly defined temporal staging of the appearance of these adaptive mechanisms, conferring ability to cope with varying environmental conditions during early development, was evident. Ontogenetic changes in MRC location, 2-dimensional surface area, density and general morphological changes were investigated in larvae incubated and reared in freshwater and brackish water (15 ppt) from hatch until yolk-sac absorption using Na+/K+-ATPase immunohistochemistry with a combination of microscope techniques. The pattern of MRC distribution was seen to change during development under both treatments, with cell density decreasing significantly on the body from hatch to 7 days post-hatch, but appearing on the inner opercular area at 3 days post-hatch and increasing significantly (GLM; p < 0.05) thereafter. Mitochondria-rich cells were always significantly (GLM; p < 0.05) denser in freshwater than in brackish water maintained larvae. In both freshwater and brackish water, MRCs located on the outer operculum and tail showed a marked increase in size with age, however, cells located on the abdominal epithelium of the yolk-sac and the inner operculum showed a significant decrease in size (GLM; p < 0.05) over time. Mitochondria-rich cells from brackish water maintained larvae from 1 day post-hatch onwards were always significantly larger (GLM; p < 0.05) than those maintained in freshwater. Preliminary scanning electron microscopy studies revealed structural differences in chloride cell morphology that varied according to environmental conditions. Mitochondria-rich cell morphology and function are intricately related and the plasticity or adaptive response of this cell to environmental changes is vital in preserving physiological homeostasis and contributes to fishes’ ability to inhabit diverse environments. Yolk-sac larvae were transferred from freshwater at 3 days post-hatch to 12.5 and 20 ppt and sampled at 24 and 48 h post-transfer. The use of scanning electron microscopy allowed a quantification of MRC, based on the appearance and surface area of their apical crypts, resulting in a reclassification of ‘sub-types’ i.e. Type I or absorptive, degenerating form (surface area range 5.2 – 19.6 μm2), Type II or active absorptive form (surface area range 1.1 – 15.7 μm2), Type III or differentiating form (surface area range 0.08 – 4.6 μm2) and Type IV or active secreting form (surface area range 4.1 – 11.7 μm2). In addition, the crypts of mucous cells were discriminated from those of MRCs based on the presence of globular extensions and similarly quantified.

Aquakultur ist essentiell um den heutigen Bedarf an Fisch als Nahrungsmittel zu decken. Einsatz von Antibiotika und Kontaminationen mit Schadstoffen in der Vergangenheit haben das Vertrauen von Verbrauchern in Fischprodukte aus Aquakulturproduktion massiv geschwächt. Zeitgleich sind die Ansprüche der Verbraucher an Qualität, Frische und Sicherheit von Lebensmitteln, aber auch das Bewusstsein, negative Auswirkungen der Lebensmittelproduktion auf die Umwelt zu minimieren, erheblich gestiegen. In der Dissertation wurde der Einsatz einer natürlichen organischen Substanz (Fulvosäure) auf die Fischgesundheit und das Immunsystem untersucht. Dabei wurde gezeigt, dass die Zugabe zum Haltungswasser bei Salmoniden und Cypriniden zu verbesserter Stressresistenz und einer Anregung des Immunsystems führte. Dies hilft den Tieren sich auf natürliche Weise gegen Krankheitserreger zu verteidigen, reduziert den Einsatz umweltschädlicher Therapeutika und steigert gleichzeitig das Tierwohl. Weiterhin führte der Zusatz der Fulvosäure zu einer signifikanten Verbesserung der Futterumsatzrate, was sich ebenfalls in gesteigertem Wachstum der Tiere widerspiegelte. Huminstoffe, zu denen die Fulvosäure zählt, sind natürlicher Bestandteil aller aquatischen Ökosysteme. Die Zugabe zum Haltungswasser stellt daher nicht nur eine umweltfreundliche, sondern auch die ursprüngliche Expositionsroute mit diesen Immunstimulanzien für aquatischen Lebewesen dar. Weiterhin besteht mit diesem innovativen Ansatz erstmals die Option die extrem empfindlichen Embryo- und Larvenstadien ohne Zusatz von Antibiotika vor Krankheiten zu schützen. Zeitgleich wird der Metabolismus stimuliert und die Larven im Schlupf und Wachstum unterstützt. Da die Sterblichkeit in diesen Stadien bei über 80 % liegen kann, eröffnen die Ergebnisse der Dissertation ein immenses Potenzial den Tierschutz zu verbessern, und sowohl die Nachhaltigkeit als auch gesellschaftliche Akzeptanz und Konkurrenzfähigkeit der Aquakultur zu steigern. / Aquaculture has become imperative to cover the dietary demand for fish as food. The use of antibiotics and contaminations with harmful substances in the past have caused a lot of prejudices for fish products from aquaculture production. At the same time, consumer standards for quality, freshness and safety of food, as well as the awareness to minimize negative impacts of food production on the environment, have increased significantly. In the dissertation, the use of a natural organic substance (fulvic acid) on the health and immune system of fish was determined. Supplementing the water resulted in improved stress resistance and a stimulation of the immune system in salmonids and cyprinids. This helps the animals to defend themselves against pathogens in a natural way, thereby reduces the use of environmentally harmful therapeutics and at the same time increases animal welfare. Furthermore, the addition of fulvic acid led to a significant improvement in feed conversion rate, which was also reflected in increased growth of the animals. Humic substances, which include fulvic acid, are a natural component of all aquatic ecosystems. Therefore, the addition to the holding water represents not only an environmentally friendly but also the original route of exposure to these immunostimulants for aquatic organisms. Furthermore, this innovative approach provides for the first time the option to protect the extremely sensitive embryo and larval stages from disease without the need of antibiotics. At the same time, the metabolism is stimulated and larvae are supported in hatching and growth. Since the mortality in these stages can be more than 80 %, the results of the dissertation show an immense potential to improve animal welfare and to increase sustainability as well as social acceptance and competitive

Made available in DSpace on 2016-08-10T10:31:08Z (GMT). No. of bitstreams: 1 RUI ALVES DE SOUZA.pdf: 1703213 bytes, checksum: bb2363e28840919d20e76e17d1aed86a (MD5) Previous issue date: 2011-02-28 / The volume of fishes raised in cages grows every year in Brazil. The reasons for this are high productivity and the possibility of good profits. When fishes are produced in earth ponds, the conventional way in semi-intensive system, productivity is close to half a kilogram per square meter. In cage system the productivity could rise from 200 kg per cubic meter. The highest density can cause reduced costs and increased profitability, but requires knowledge, training and dedication of the profissional. In this study the goal was to assess the sustainability of the venture, with the help of indicators of economic, environmental and social issues. We lived with relatives of the settlers by INCRA in the "Settlement Project Santa Felicidade, " in Cocalzinho de Goiás - GO, the creation of tambaqui (Colossoma macropomum) in cages, covering the main dimensions of sustainable development and the proven economic viability, financial enterprise. Feasibility analysis conducted has shown that the return on invested capital occurred in the medium term. Spread the viability of the enterprise and laborintensive participatory in intensive fish farming. / O volume de peixes criados em tanque-rede cresce a cada ano no Brasil e os motivos desse crescimento são alta produtividade e possibilidade de bons lucros. Quando o peixe é produzido em viveiro escavado, pela forma convencional em sistema semi-intensivo, a produtividade fica próxima de meio quilo por metro quadrado. No sistema de tanques-rede, a produtividade pode passar dos 200 kg por metro cúbico. A maior densidade pode provocar redução dos custos e aumento da rentabilidade, entretanto requer conhecimento, treinamento e dedicação. No presente trabalho, o objetivo foi analisar a sustentabilidade do empreendimento, com o auxílio de indicadores econômicos, ambientais e sociais. Foram vivenciadas, com familiares dos assentados pelo INCRA no Projeto de Assentamento Santa Felicidade , em Cocalzinho de Goiás GO, a criação de tambaqui (Colossoma macropomum) em tanques-rede, contemplando as principais dimensões do desenvolvimento sustentável e comprovada a viabilidade econômico-financeira do empreendimento. As análises de viabilidade realizadas demonstraram que o retorno do capital investido ocorreu em médio prazo. Difundiu-se a viabilidade do empreendimento e da mão-de-obra participativa na criação intensiva de peixes.

Among efforts to develop sustainable approaches towards the intensive rearing of finfish within open marine waters, is the development of integrated aquaculture techniques. Integrated Multi-Trophic Aquaculture (IMTA), has been promoted as a way to reduce unwanted environmental impacts associated with the intensive production of marine finfish within net-pens. The principle aim of this concept, is the bioremediation of nutrient discharges from fish aquaculture. This is to be achieved by integrating fish cultivation with the growing of species from lower trophic levels, which use the nutrient discharges as a food source. Many studies have been performed that investigate the ability of various species of macroalgae to remove dissolved nutrient discharges, and the ability bivalves to remove solid-bound nutrients, presented as either fish faeces, or an enhanced production of phytoplankton that may be promoted by nutrients emitted by fish-farms. IMTA has also been suggested as a means to improve overall productivity per unit of feed applied to fish, through the conversion of nutrient emissions into additional biomass, such as the tissues of macroalgae or bivalves. Within the research community which focuses upon the environmental impacts of aquaculture, there is a growing awareness that sustainable solutions to aquaculture production cannot be realised through a focus restricted to the growing-phase, and to a limited set of environmental impacts which may this activity may produce. This is because changes to a specific production phase often promote changes at phases located elsewhere along a products value chain. Life-Cycle Assessment (LCA), is a method employed for modelling the environmental impacts that may potentially be generated across the value chain of a product. It is particularly useful for identifying instances of environmental impact shifting; a term used to describe situations where efforts to reduce the contribution of a specific production phase towards one or more environmental impacts, has the effect of either displacing this contribution to another phase, or increases the contribution of production towards different environmental impacts. Despite its apparent suitability, LCA has not previously been fully applied to the environmental impact modelling of open-water IMTA systems. The work presented in the following thesis advances this research front, by using LCA to explore the potential for environmental problem shifting occurring as a consequence of replacing intensive monoculture production, with IMTA. Comprehensive datasets have been acquired from the Chilean aquaculture industry, describing the production of aquafeed and Salmo salar, as well as for the production of the Phaeophytic macroalga, Macrocystis pyrifera, and the molluscan bivalve, Mytilus chilensis. Using LCA methodology, the production of salmon feed, and the production of S.salar, M.pyrifera and M.chilensis, have been assessed for their capacity to contribute towards a variety of global-scale, environmental impacts. IMTA consisting of either S.salar and M.pyrifera, S.salar and M.chilensis, or all three of these species, and combined at ratios required for a bioremediation efficiency of 100 %, 50%, or 20 % of either nitrogen or phosphorous emission from fish, is compared to the monoculture production of S.salar. The comparison is based upon a standardised functional unit, with each species produced through IMTA, being modelled as part of the reference flow required to fulfil the functional unit. Monoculture is compared to IMTA upon the basis of nutritional function, by using a functional unit of mass-adjusted protein content, and mass-adjusted economic value. The use of economic value is based upon the ‘best-case’ assumption, that it serves as a proxy for the total nutritional function that each product offers to human society. The LCAs presented in this study have produced a number of results. Salmon ingredients derived from agricultural crops and animals account for the majority (between 71 % to 98 %) of contributions towards the impacts of compound salmon feed. In general, agricultural crops ingredients contribute more to these impacts than do agricultural animal ingredients, and account for between 31 % and 87 % of the contributions from all ingredients and inputs. In contrast, the combined supply of fish meal and fish oil from capture fisheries is responsible for between 0.13 % and 11 % of all impacts. Vegetable oil accounts for the vast majority of contributions from ingredients derived from agricultural crops. Vegetable oil is modelled as a 50 : 50 blend of sunflower oil and rapeseed, oil, but sunflower oil accounts not only for most of the contributions from vegetable oil, it is responsible for over 50 % of the contributions that all agricultural crop based ingredients contributes towards some impact categories. Replacing sunflower oil with rapeseed oil reduces the contributions of salmon feed by between 6 % and 24 % across 10 out of the 11 impact categories. When compared upon the basis of equal weight, the contributions of fish oil are between 18 % and 99 % lower than those from rapeseed oil. The production of feed is responsible for the majority of contributions (between 32 % and 86 % ) to all impacts of salmon grow-out production. The production of salmon-smolts accounts for between 3 % and 18 %. The majority (64 %) of contributions towards the eutrophication potential of salmon production are from nutrient emissions, which are the result of fish metabolism, whilst nutrients released through the production of feed, the majority of these being from the agricultural production of crop and animals, account for 32 %. Feed production is also a major contributor to the impacts of land-based smolt production, but these contributions (between 12 % and 37 % across all impact categories) are of a lower magnitude than those from the supply of feed to the grow-out phase. Inputs of salt, and inputs of both electricity produced in a diesel power generator and obtained from the national electricity network, are also notable contributors (between 5 % and 67 %, 4 % and 29 %, and 2 % 47 %, respectively) towards the impacts of smolt-production. The main contributors towards the potential impacts of kelp grow-out production (excluding eutrophication potential) are the supply of infrastructure (between 14 % and 89 %), operation of a diesel-powered motorboat for maintenance purposes (between 1 % and 89 %), and the supply ‘of seeded cartridges’ (between 9 and 49 %). The major contributors from the production of ‘seeded cartriges’ in a land-based facility are the supply of electricity from the national electricity network, the supply of fresh water, and the treatment of waste water. The impact potentials of producing seed in this facility might be reduced if the scale of operation is increased. Removal of nitrogen and phosphorous upon the harvesting of kelp is calculated based upon kelp tissue contents of these nutrients. The harvesting of 200 tonnes ha / yr-1, results in a eutrophic potential with a negative value (-376.51 kg of phosphate equivalents). The removal of such a quantity of nutrients might be beneficial if the local marine environment is at risk of hypernutrification, but when no such problem is present, the potential for undesirable consequences of nutrient sequestration should be considered. The major contributor towards the impacts of mussels is the provision of infrastructure (between 25 % and 99.5 %, excluding eutrophication potential). Infrastructure is also responsible for the majority of contributions from mussel seed production. The provision of cotton mesh bags, which are used to aid attatchment of seed to drop-ropes in the grow-out phase, account for between 37% and 99 % of the contributions from the infrastructure from the grow-out phase. This result suggest that either the impacts of mussel production can be reduced by using an alternative material with lower environmental impact potentials, or the inventory data describing the producing of cottonmesh bags requires some improvement. The outcomes of the LCAs of the different IMTA scenarios, are interesting. The results show that choice of species, and the ratios of their combination as required for the different efficiencies of bioremediation, can have a significant effect upon the comparison between IMTA and monoculture. / The study demonstrates a potential for environmental problem shifting as being a consequence of IMTA, especially when the functional unit is mass-adjusted economic value. As bioremediation efficiency increases, contributions towards eutrophication decrease. However, this reduction is achieved at the cost of increasing the contributions of IMTA towards those impact categories, such as ‘ozone layer depletion,’ for which it has a greater contribution than does monoculture. In general, it cannot be concluded from these results that open-water IMTA represents a more sustainable alternative to the monoculture production of Atlantic salmon. The sustainability of IMTA is shown to be dependent upon a variety of trade-offs, between individual environmental impacts, and between these impacts and the nutritional function that the system is capable of providing.