No description available.

No description available.

Open net-pen aquaculture allows for free exchange of materials between farm and wild environments. Increased habitat complexity in the form of farm infrastructure produces effects similar to fish aggregating devices and artificial reefs, altering the distribution and abundance of fish species within the greater area. The continuous input of nutrients via fish waste and uneaten food pellets can amplify such effects, leading to large and persistent aggregations of wild fish near aquaculture sites. These aggregations have been quantified in numerous geographical locations but data are lacking for salmon farms in coastal British Columbia. The footprint of the attractive effects is also poorly understood in all cases as research has focused on fish populations directly associated with the infrastructure. In this study wild fish populations were quantified at shallow rocky ecosystems adjacent to salmon farms in the Broughton Archipelago and compared to paired reference sites with similar habitat characteristics to test for aggregating effects. Two SCUBA divers performed visual surveys along six 25x4x4m transects at each site, three at each of two depth ranges: deep (12-16m) and shallow (6-10m). Species, abundance, and estimated total length, as well as temperature, salinity, rugosity, and visibility were examined. A combination of multivariate and univariate statistical analysis were performed to compare the physical characteristics, community composition, number of individuals, and biomass between farms and reference sites. The overall community composition was significantly different at farm sites despite no difference found in the physical habitat characteristics between treatments. This difference was predominantly driven by five fish species, yellowtail rockfish (Sebastes flavidus), copper rockfish (Sebastes caurinus) quillback rockfish (Sebastes maliger), shiner perch (Cymatogaster aggregata) and striped perch (Embiotoca lateralis). Presence/absence data showed no significant difference in species identity between farms and references, implying that the difference in community composition was primarily driven by changes in abundance rather than species identity. The total number of fish and biomass of all fish species was also significantly higher at farms. These results suggest that salmon farms in the Broughton Archipelago alter the community structure and increase the abundance of near-field wild fish populations. The aggregating effects are asymmetric within the community, with higher trophic level species showing the greatest increases in abundance. The potential implications of these results include a greater risk of disease and parasite transfer between farm and wild fish, as well as within each population. The ecological relationships among species may also be compromised with predator amplified communities potentially exhibiting top-down effects on the rest of the food web. Changes to wild fish communities seen up to 170m away from farm infrastructure suggest that the mechanism of the attractive effects may be driven more by nutrient subsidies than the presence of infrastructure. This work underscores the need to determine the full spatial extent and mechanisms of attractive effects as well as the ecological implications of persistent aggregations of wild fish near salmon farms. / Graduate

No description available.

Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is there any correlation between genetic similarity and the potential for hybridization in marine fishes? In some particular geographic locations that have the existence of several different hybridization reports, are the species involved in hybridization among those reports all closely related or distantly related? Can any associations between parent species’ similarities and hybrid spots be found?

Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-13Bitstream added on 2014-06-13T18:40:43Z : No. of bitstreams: 1 machado_mrf_dr_jabo.pdf: 654283 bytes, checksum: 42d2b7787949eced9fba27ca7e496f5b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Os recursos pesqueiros marinhos representam uma importante fonte de proteína e, além de alimento, é fonte de renda para milhares de pessoas, especialmente nos países em desenvolvimento. Muitos estoques pesqueiros naturais já se encontram em seu limite máximo de exploração, devido a isso houve um aumento considerável da produção de pescado pela aquicultura nos últimos anos. As maiores deficiências tecnológicas ainda residem no cultivo de peixes marinhos, que vem sendo um dos principais entraves à produção, área em que o país ainda está em fase embrionária. Dentre as espécies marinhas mais estudadas no Brasil destacamos o gênero Centropomus (robalo) que possui uma dificuldade do manejo de reprodutores em cativeiro e dificuldades em formular a ração para esses peixes, dificultando dessa forma a sua produção. Porém faltam estudos na área de morfologia, fisiologia e nutrição para as espécies marinhas. Dessa forma, foi realizado o presente trabalho com o objetivo de identificar os principais componentes alimentares de jovens de robalo peva (Centropomus parallelus) e robalo flexa (Centropomus undecimalis) por análises histológicas e histoquímicas do sistema digestório, determinação de isótopos estáveis e verificar, por meio de proteômica, quais as proteínas presentes no fígado são expressas na alteração da dieta desses peixes. Esse estudo pretende fornecer subsídios para o desenvolvimento de um pacote tecnológico para o cultivo de ambas as espécies, contribuindo na otimização da nutrição e gerando alternativas para tornar a piscicultura marinha uma atividade produtiva no país / The marine fishery resources represent an important source of protein and, besides food, is a source of income for thousands of people, especially in developing countries. Many natural fish stocks are already at their limit of exploitation because of this there was a considerable increase in fish production through aquaculture in recent years. The major technological deficiencies still reside in the cultivation of marine fish, which has been a major constraint to production, the area where the country is still in its infancy. Among the most studied marine species in Brazil include the genus Centropomus (bass) that has a difficulty in handling of captive broodstock and difficulties in formulating the ration for these fishes, thus hindering their production. But lacks studies on morphology, physiology and nutrition for marine species. Thus, the present work was undertaken with the aim of identifying the major dietary constituents of young fat snook (Centropomus parallelus) and bass arrow (Centropomus undecimalis) by histological and histochemical digestive system, determination of stable isotopes and verify by using proteomics, which proteins are expressed in liver in changing the diet of these fish. This study aims to provide subsidies for the development of a technology package for cultivation of both species, contributing to the optimization of nutrition and generating alternatives to marine fish farming to become a productive activity in the country

Orientador: Alpina Begossi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T00:57:23Z (GMT). No. of bitstreams: 1 Gianeli_ArlainedosSantosFrancisco_M.pdf: 807934 bytes, checksum: 343bcda056eb75e72a1cf338b739b983 (MD5) Previous issue date: 2007 / Resumo: A interação cotidiana com o ambiente marinho e com seus organismos leva pescadores artesanais a acumularem um conhecimento rico e particular acerca da biologia, da ecologia e da taxonomia de peixes. Assim, informações fornecidas pelos pescadores podem servir de subsídio para estudos ictiológicos, planos de conservação e manejo pesqueiro. Este estudo foi desenvolvido na Praia do Perequê, litoral de São Paulo, e é parte do projeto temático da BIOTA-FAPESP, subprojeto "Etnoecologia do Mar e da Terra na Costa Paulista da Mata Atlântica: Áreas de Pesca e Uso de Recursos Naturais". A Praia do Perequê está localizada na periferia do município do Guarujá e sofre as conseqüências da urbanização desordenada. O local abriga uma comunidade de pescadores que se dedicam à pesca do camarão e de peixes diversos. Os meus objetivos foram: traçar o perfil de pescadores de peixes e de camarão; inventariar as técnicas empregadas na captura das espécies estudadas; verificar e comparar com a literatura científica o conhecimento dos pescadores sobre habitat, dieta, reprodução e migração de peixes; analisar os critérios que os pescadores usam na classificação dos peixes. As informações foram obtidas com a utilização de questionários padronizados e fotos das espécies estudadas. Observei que os pescadores de camarão são em sua maioria migrantes provenientes de Santa Catarina, enquanto os pescadores de peixe são, na maioria, caiçaras nascidos no local. As técnicas de pesca são adequadas ao ambiente de captura do pescado e a escolha de iscas está relacionada com o hábito alimentar de cada espécie. Pescadores de peixe e camarão demonstraram conhecimento similar sobre técnicas de pesca. Tal similaridade pode ocorrer porque os dois grupos desenvolvem as atividades pesqueiras no mesmo local e entre as famílias de pescadores estão presentes membros que desenvolvem ambas as modalidades de pesca, o que pode propiciar a partilha do conhecimento. Em geral o conhecimento etnoecológico é condizente com o conhecimento científico. Tanto pescadores de peixe quanto os pescadores de camarão conhecem o habitat e a dieta das espécies mais capturadas, como: robalo, tainha, corvina, espada e garoupa. Ambos os grupos de pescadores fazem inferências sobre habitat e dieta a partir de aspectos morfológicos dos peixes. Conhecimentos sobre migração e reprodução por sua vez, foram mais escassos entre os pescadores estudados. Os pescadores apontam períodos específicos para ocorrência de tainha, corvina e anchova: a tainha e a corvina foram apontadas como espécies que se reproduzem no inverno, enquanto o robalo, o badejo e a garoupa se reproduzem em meses quentes. Essas espécies são de grande interesse comercial, o que pode explicar o conhecimento mais detalhado sobre elas em comparação com outras espécies menos conhecidas e de menor valor. Os pescadores do Perequê utilizaram a nomenclatura binomial especialmente em casos de ocorrência de mais de uma espécie por etnogênero. Os etnogêneros foram agrupados em etnofamílias principalmente de acordo com critérios morfológicos. As informações fornecidas apontaram particularidades que podem ser úteis no delineamento de planos de manejo adequados ao ambiente e à pesca local / Abstract: Artisanal fishermen can provide an elaborate and particular knowledge about biology, ecology and taxonomy of fish and about the ecosystem which they interact with. This knowledge is local and resulted from a continuity of resources use practices. Information supplied by fishermen can be the base for improvements of scientific research and to subsidis for conservation and fishery management plans. This study was conducted in the Perequê Beach, coast of São Paulo State. Perequê Beach is located in the periphery of the city of Guarujá, and suffers consequences of the disordered urbanization. Local people are dedicated especially to the shrimp and diverse fish fishery. The aims of this study were: to characterize local fishermen and fishery; to access the fishermen¿s knowledge concerning fish habitat, diet, reproduction and migration; to analyze the criteria that fishermen use in the classification of fish and to compare this knowledge with the scientific literature. Interviews using questionnaires and fish photographs were performed to obtain information regarding fishermen economical and social aspects and fish biology and ecology. The majority of shrimp fishermen are from Santa Catarina state while the fish fishermen are usually ¿caiçaras¿, local native. Fishery technologies and techniques are adjusted according to the environment and feeding habits of the target species. Both fish and shrimp fishermen demonstrated similar knowledge on fishes. Probably it can be related to the fact that both groups develop their activities in the same local and are members of families that develop the two modalities of fishery, sharing their knowledge. In general, the ethnoecological knowledge is in concordance with the scientific literature. Both fish and shrimp fishermen know the habitat and diet of the main fished species, as: snook (Centropomus spp.), mullet (Mugil platanus), croaker (Micropogonias furnieri), and groupers (Epinephelus marginatus e Mycteroperca acutirostris). Both fishermen groups make inferences on habitat and diet based on morphologic aspects. Knowledge on migration and reproduction was scarcer. The fishermen points out specific periods in respect to occurrence of mullet (M. platanus), croaker (M. furnieri) and bluefish (Pomatomus saltatrix). Mullet and croaker was suggested as a species that reproduces during the winter, while snook, and the groupers (E. marginatus e M. acutirostris) reproduce in hot months. These species have a great commercial interest that can explain the more detailed knowledge in detriment of others of lesser value. The Perequê fishermen use the binomial classification particularly in cases where there are more than one species in the same genus. The species were grouped in ethnofamilies mainly in accordance with morphologic criteria. The supplied information suggested particularities that can be useful in the management plans delineation in compliance with environment and its fishery place / Mestrado / Ecologia / Mestre em Ecologia

Submitted by (edna.saturno@ufrpe.br) on 2016-08-25T13:26:26Z No. of bitstreams: 1 Elizete Teresinha Santos Cavalcanti.pdf: 3838205 bytes, checksum: 682e48c0d8e77d8e94fb9b5eec7459ef (MD5) / Made available in DSpace on 2016-08-25T13:26:27Z (GMT). No. of bitstreams: 1 Elizete Teresinha Santos Cavalcanti.pdf: 3838205 bytes, checksum: 682e48c0d8e77d8e94fb9b5eec7459ef (MD5) Previous issue date: 2012-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This study investigated about the parasites of marine fishes which are of commercial value from the coastal waters of Rio Grande do Norte, Brazil. The following fishes were captured, mullet, Mugil curema, lane snapper, Lutjanus synagris, Serra Spanish mackerel,Scomberomorus brasiliensis, Atlantic cutlassfish, Trichiurus lepturus and the Southern red snapper, Lutjanus purpureus during the period March, 2006 to April, 2009. The parasites encountered were collected, observed, identified and counted. M. curema was parasitized by various crustacean ectoparasites: caligidean copepods (Caligus bonito and Caligus sp.), ergasilidean copepods (Ergasilus versicolor and E. lizae) and isopod (Cymothoa spinipalpa).Presence of the endoparasitic acanthocephalan Neoechinorhynchus curemai was also registered in mullet. The occurrence of endoparasitic nematode Philometra sp. was registered for the first time in lane snapper. The endoparasites such as, nematode Contracaecum fortalezae and trematode Didymocystys sp. were observed in Serra Spanish mackerel. The endoparasites such as, nematode Hysterothylacium sp. and digenetic Catarinatrema verrucosum were encountered for the first time in the Atlantic cutlassfish. In the Southern red snapper the following endoparasites were registered, five nematodes (Anisakis simplex,Contracaecum sp., Hysterothylacium sp., Raphydascaris sp., and Procamallanus), one cestode (Callitetrarhynchus gracilis) and two acanthocephalans (Serrasentis sp. and Acanthocephalus sp.). These parasitic diseases are still poorly known and possibly the diagnosis is not being done properly. These results show the need for a comprehensive explanation to the local population and owners of establishments who sell this product regarding the occurrence of parasites, and also to alert the competent authorities for the need to adopt preventive measures. / O presente trabalho investigou sobre os parasitos dos peixes marinhos de valor comercial das águas costeiras do Rio Grande do Norte, Brasil. Foram capturados os peixes tainha, Mugil curema, ariacó, Lutjanus synagris, serra,Scomberomorus brasiliensis, espada, Trichiurus lepturus e pargo, L. purpureus durante o período de março de 2006 a abril de 2009. Os parasitos encontrados foram coletados, observados, identificados e quantificados. M. curema foi parasitado por vários crustáceos ectoparasitos: caligídeos (Caligus bonito e Caligus sp), ergasilídeos (Ergasilus versicolor e E. lizae) e isópode (Cymothoa spinipalpa). Também foi registrada na tainha a presença do endoparasito acantocéfalo Neoechinorhynchus curemai. Foi registrada a ocorrência do endoparasito nematódeo Philometra sp. pela primeira vez em ariacó. Os endoparasitos, nematódeo Contracaecum fortalezae e o trematódeo Didymocystys sp. foram observados na serra. O nematódeo Hysterothylacium sp. e trematódeo Catarinatrema verrucosum foram encontrados pela primeira vez no peixe espada. No pargo foram registrados cinco nematódeos (Anisakis simplex, Contracaecum sp., Hysterothylacium sp., Raphydascaris sp. e Procamallanus), um cestódeo (Callitetrarhynchus gracilis) e dois acantocéfalos (Serrasentis sp e Acanthocephalus sp). Essas parasitoses ainda são doenças pouco conhecidas e possivelmente o diagnóstico não esteja sendo realizado devidamente. Estes resultados comprovam a necessidade de uma vasta explanação junto à população e proprietários dos estabelecimentos que comercializam esse produto, sobre a ocorrência destas parasitoses em nosso meio, e por outro lado alertar as autoridades competentes para a necessidade de adoção de medidas de prevenção.

Marine water contains large numbers of fish spoilage bacteria and pathogens including V. cholerae, V. parahaemolyticus, and V. vulnificus. Consumption of contaminated seafood could lead to the transmission of these pathogens to humans. Accurate identification of suspected pathogens and spoilage organisms is important to ensure consumer safety and a long shelf life. This project assessed the bacterial quality of hake during processing. Some attention was also given to pilchards and horse mackerel. The results showed a sharp increase in the mesophilic and sucrose fermenting Vibrio species counts in hake after filleting. It has been suggested that this contamination occurred during processing from biofilms present in the sea-water distribution system. During the study 257 strains isolated from Thiosulphate citrate bile salts sucrose (TCBS) agar were screened to determine the presence of the pathogenic Vibrios amongst these isolates. It was difficult to distinguish between V. alginolyticus and V. parahaemolyticus species due to high sequence similarity in their 16S rRNA genes. Final identification of the isolates required a polyphasic approach and it was found that none of the pathogenic Vibrios were present but that the Vibrio isolates mainly belonged to V. alginolyticus. As it was suspected that the main source of contamination was the treated sea water used during processing the ability of chlorine, ozone and hydrogen peroxide to prevent biolfilm formation was examined. The behaviour of two V. alginolyticus strains (V590 and V595) isolated from the processed hake was evaluated. These strains formed biofilms faster than the V. alginolyticus LMG4409 type strain, but were similar to V. parahaemolyticus LMG2850. Biofilms formed by these bacteria were resistant to 4 mg/l chlorine and to 2 mg/l ozone, but were inhibited by 0.05 % and 0.2 % hydrogen peroxide for biofilms initiation and mature biofilms respectively. The close resemblance of atypical V. alginolyticus isolates to V. parahaemolyticus may indicate the ability of pathogens to survive under similar conditions. Effective decontamination and quality assurance strategies are therefore required when processing fish to prevent disease outbreaks. / Thesis (PhD)--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted

Resumo: Os recursos pesqueiros marinhos representam uma importante fonte de proteína e, além de alimento, é fonte de renda para milhares de pessoas, especialmente nos países em desenvolvimento. Muitos estoques pesqueiros naturais já se encontram em seu limite máximo de exploração, devido a isso houve um aumento considerável da produção de pescado pela aquicultura nos últimos anos. As maiores deficiências tecnológicas ainda residem no cultivo de peixes marinhos, que vem sendo um dos principais entraves à produção, área em que o país ainda está em fase embrionária. Dentre as espécies marinhas mais estudadas no Brasil destacamos o gênero Centropomus (robalo) que possui uma dificuldade do manejo de reprodutores em cativeiro e dificuldades em formular a ração para esses peixes, dificultando dessa forma a sua produção. Porém faltam estudos na área de morfologia, fisiologia e nutrição para as espécies marinhas. Dessa forma, foi realizado o presente trabalho com o objetivo de identificar os principais componentes alimentares de jovens de robalo peva (Centropomus parallelus) e robalo flexa (Centropomus undecimalis) por análises histológicas e histoquímicas do sistema digestório, determinação de isótopos estáveis e verificar, por meio de proteômica, quais as proteínas presentes no fígado são expressas na alteração da dieta desses peixes. Esse estudo pretende fornecer subsídios para o desenvolvimento de um pacote tecnológico para o cultivo de ambas as espécies, contribuindo na otimização da nutrição e gerando alternativas para tornar a piscicultura marinha uma atividade produtiva no país / Abstract: The marine fishery resources represent an important source of protein and, besides food, is a source of income for thousands of people, especially in developing countries. Many natural fish stocks are already at their limit of exploitation because of this there was a considerable increase in fish production through aquaculture in recent years. The major technological deficiencies still reside in the cultivation of marine fish, which has been a major constraint to production, the area where the country is still in its infancy. Among the most studied marine species in Brazil include the genus Centropomus (bass) that has a difficulty in handling of captive broodstock and difficulties in formulating the ration for these fishes, thus hindering their production. But lacks studies on morphology, physiology and nutrition for marine species. Thus, the present work was undertaken with the aim of identifying the major dietary constituents of young fat snook (Centropomus parallelus) and bass arrow (Centropomus undecimalis) by histological and histochemical digestive system, determination of stable isotopes and verify by using proteomics, which proteins are expressed in liver in changing the diet of these fish. This study aims to provide subsidies for the development of a technology package for cultivation of both species, contributing to the optimization of nutrition and generating alternatives to marine fish farming to become a productive activity in the country / Orientador: Roberto Goitein / Coorientador: Alexandre de Azevedo / Banca: Rosangela Kiyoko Jomori Bonichelli / Banca: Leonardo Gomes da Silva / Banca: Helton Carlos Delicio / Banca: Antonio Fernando Gervásio Leonardo / Doutor