In the past, oceans have strongly influenced atmospheric CO2 levels through organic and inorganic carbon cycling. The inorganic carbon pump relies on the formation of calcium carbonate which releases CO2 into the surface ocean and traps alkalinity in solid form which sinks to deeper ocean layers and sediments. After sinking, calcium carbonate can either then become trapped in the sediments or dissolve increasing the alkalinity of deeper ocean layers. The net effect is of acidifying surface oceans and encouraging release of CO2 to the atmosphere. The present thesis focuses on marine teleost (bony) fish in temperate areas as previously poorly understood but potentially major producers of calcium carbonate in the ocean. Fish in temperate areas may be contributing to carbonate sediment production and as such the inorganic carbon pump. Prior to this thesis only tropical fish have been investigated as major piscine sediment producers. The present thesis describes the composition and morphology of carbonates produced by many different species of temperate fish providing a basis for the understanding the fate of these carbonates in the environments and their potential contribution to sediment production and the inorganic carbon cycle. Characteristics of carbonates produced by fish in the wild were fairly consistent within a species upon examination of carbonates produced by poor cod (Trisopterus minutus) over the course of a year. However, despite the likely consistent and distinct characteristics of fish carbonates, little evidence of them was found in temperate shallow sediments beneath pens of farmed Atlantic salmon (Salmo salar) where there theoretically should be very high production rates. Reduced salinity, often a feature of temperate areas compared to tropical areas, was found to reduce production rates of carbonate from fish compared to higher salinities. However, salinity reductions below the ocean average of 35 psu (practical salinity units) had less impact on production rates than increases above 35 psu. As such it is argued that production rates in temperate environments should still be relatively high considering high fish biomasses in some temperate regions and could still mean fish in temperate areas are an important source of carbonate production and potential sediment production.

Resumo: Com o intuito de conhecer o potencial zootécnico do pampo, foi avaliado o efeito de diferentes densidades de estocagem (100 e 200 peixes/m3) na sobrevivência e crescimento do pampo amarelo (Trachinotus carolinus), criado em tanque-rede instalado em ambiente marinho. Peixes com aproximadamente 1,0 a 2,0 g, capturados em arrastos nas praias rasas do município de Ubatuba, SP, foram transportados ao Núcleo de Pesquisa e Desenvolvimento do Litoral Norte - Agência Paulista Tecnológica do Agronegócio - Secretaria da Agricultura e Abastecimento e mantidos durante 45 dias em tanques-rede de 5mm de malhagem. Após seleção manual, animais de 4,0 ± 0,17g foram estocados, nas densidades de 100 e 200 peixes/m3, em tanques-rede de multifilamento com 2 x 2 x 1,5m e 12 mm de malhagem, fixos a um "deck" flutuante (6,0 x 8,0 m), instalado diretamente no mar a profundidade de aproximadamente 3,5 ± 0,5 m. Os animais foram alimentados duas vezes ao dia até a saciação com ração de 40% de PB. Após 120 dias, as taxas de sobrevivência média observadas foram 77,23% e 73,11 %; pesos médios (52,79 ± 4.86 9 e 52,64 ± 5.64 g); Ganho de Peso (GP) (48,69 ± 4,05 9 e 48,73 ± 4,00 g); Taxa de Crescimento Especifico (TCE) (2,13 ± 1,24 e 2,16 ± 1,03) e Conversão Alimentar Aparente (CAA) (3,23 ± 1,52 e 2,66 ± 0,78), respectivamente para 100 e 200 peixes/m3. Estes dados não apresentaram diferenças significativas (P~0,05) entre os tratamentos testados. Entretanto os ganhos de peso do pampo, no presente experimento foram superiores a muitos trabalhos encontrados na literatura, o que nos leva a concluir que a densidade de 200 peixes/m3, utilizada neste estudo, pode ainda estar abaixo da capacidade de suporte para a espécie e pode ser o ponto de partida para futuros estudos, considerando o estágio de desenvolvimento dos animais. / Abstract: Aiming to know the zoothecnic potential of pampo, it was evaluated the effect of stocking densities (100 and 200 fish/m3) in the survival and growth rates of Florida pampano (Trachinotus carolinus), reared in marine cage. Fish with approximately 1 - 2g captured by seine in flat beaches of the city of Ubatuba, S.P. were transferred to the Núcleo de Pesquisa e Desenvolvimento do Litoral Norte - Agencia Paulista Tecnologica do Agronegocio - Secretaria Agricultura e Abastecimento and kept during 45 days in cage of 5mm mesh size. After manual selection, animals of 4.0 ± 0.17g had been stored, in the studied densities, cage of multifilament with 2 x 2 x 1.5 m and 12 mm of mesh size fixed to a"deck" (6.0 8.0 m), installed directly in the sea at a depth of approximately 3.5 ± 0.5 m. The animals had been fed twice¬-a day until satiation with ration of 40% of PB. Soon after a 120 days experimental period, the average survival rate (77.23% and 73.11 %); average body-weight (52.79 ± 4.86 and 52.64 ± 5.64); weiht gain (48.69 ± 4.05 and 48.73 ± 4.00); daily growth increment (2.13 ± 1.24 and 2.16±1.03) and apparent feed conversion rate (3.23 ± 1.52 and 2.66 ± 0.78), respectively for 100 and 200 fish/m3,were recorded. These parameters didn't present significant differences (P>=0,05) between the tested treatments. However pampo weight gain, in this experiment have been superior to many works found in literature, what allows the conclusion that pampo can be reaise in sea cages in densities above 200 fish/m3, and this density could be the starting point for future studies. / Orientador: Newton Castagnolli / Coorientador: Sérgio Ostini / Banca: João Donato Scorvo Filho / Banca: João Batista Kochenborger Fernandes / Mestre

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Aqüicultura, Instituto de Oceanografia, 2011. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2012-08-17T01:12:42Z No. of bitstreams: 2 furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-09-22T18:10:17Z (GMT) No. of bitstreams: 2 furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) / Made available in DSpace on 2012-09-22T18:10:17Z (GMT). No. of bitstreams: 2 furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) furg - dissertao maria angelica dos reis garrido pereira.pdf: 911472 bytes, checksum: 983e6452fd9febc8f8a9a026e1fce50b (MD5) Previous issue date: 2011 / O bijupirá (Rachycentron canadum) é um peixe marinho que apresenta bom potencial para seu cultivo. Muitas pesquisas demonstram os efeitos benéficos do probiótico Bacillus spp. na aquicultura, porém não há estudos sobre os efeitos de probióticos em sistemas de recirculação de água (SRA). Este trabalho analisa os efeitos do probiótico Bacillus spp. na performance de larvas de bijupirá criadas em SRA. O experimento foi realizado na Universidade Virginia Tech (EUA). As larvas foram estocadas em dois SRA independentes entre si - tratamento probiótico (TP) e tratamento controle (TC) - na densidade de 15 larvas/L, durante 26 dias após a eclosão. Um dos sistemas (TP) recebeu a adição de probiótico comercial composto por B. subtilis, B. licheniformis e B. pumilus diretamente na água e via alimento vivo, conforme o fabricante. As análises de microbiologia e qualidade de água foram feitas diariamente por medição de parâmetros físico e químicos e plaqueamento em meio de cultura para contagem de Bacillus totais e Vibrio totais. Ao final do experimento foram realizados biometria e contagem total dos animais, teste de resistência ao estresse salino e fixação de larvas para imunohistoquímica do timo para avaliar a expressão dos complexos multirreceptores de antígenos CD3 e CD4 de linfócitos T e morfometria do rim cefálico. A sobrevivência foi similar e de 14,9±2,4% e 15,1±0,9% para TP e TC respectivamente. O peso final foi de 170±10 mg para TP e 160±10 mg TC, não havendo diferença estatística entre os tratamentos. Na microbiologia da água não foram encontradas diferenças significativas entre os tratamentos na contagem de víbrios totais (TP: 3.366±522 UFC/mL; TC: 4.964±902 UFC/mL). Na contagem de Bacillus totais os tratamentos diferiram estatisticamente, sendo maior a concentração no TP pela adição dos Bacillus spp. (901±88 UFC/mL e 61±24 UFC/mL). O teste de estresse por salinidade demonstrou uma maior resistência ao estresse salino pelas larvas do tratamento probiótico. A análise imunohistoquímica mostrou uma maior expressão de CD4 no timo em PT (TP: 43,7 ± 6,16% CD4 células/mm²; TC: 25,4 ± 3,5% CD4 células/mm²), o que pode indicar uma melhor resposta imune contra patógenos. A análise morfométrica do rim cefálico indica que este órgão é maior no TP (TP: 0,97 ± 0,33 milímetros; TC: 0,69 ± 0,22 milímetros), provavelmente devido a um aumento na quantidade de linfócitos B. Estes resultados indicam que o probiótico utilizado em um sistema de recirculação de água é efetivo quanto à imunoestimulação e aumenta a resistência ao estresse salino. / Cobia (Rachycentron canadum) is a marine finfish with good potential for mariculture. The aim of this study was to analyze the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS). Many studies have demonstrated the beneficial effects of probiotic Bacillus spp. in aquaculture, but there are no studies on the effects of probiotics in RAS, requiring research on their effectiveness, since in open systems the beneficial effects are already known. The trial was conducted at Virginia Tech VSAREC (USA). Larvae were stocked into two independent RAS - probiotic treatment and control - at a density of 15 larvae L-1, for 26 days after hatching. One of the systems (Probiotic treatment) received the addition of a commercial probiotic consisting of Bacillus subtilis, Bacillus licheniformis and Bacillus pumilus directly into the water and by live feed, according to the manufacturer. At the end of the experiment we performed biometrics, larvae counts, stress test and larvae were fixed for morphometric analysis of head kidney and for immunohistochemistry of thymus to evaluate the phenotypic expression of complex antigens CD3 and CD4 in T-lymphocytes. Survival and final weight had no significant difference between groups. The analysis of water microbiology had no significant differences between treatments in total counts of Vibrio, but in the total count of Bacillus treatments differed statistically, with a higher concentration in Probiotic treatment because of the addition of Bacillus spp. in this group. The salinity stress test was expressed by stress sensitivity index (SSI), which demonstrated a greater resistance to salt stress by larvae of probiotic treatment. Immunohistochemical analysis showed a higher expression of CD4 in Probiotic treatment, which may indicate better immune response against pathogens. The morphometric analysis of head kidney indicates that this organ is larger in Probiotic treatment, probably due to an increase in the quantity of B-lymphocytes. These results indicate that Bacillus spp. probiotics used in RAS may stimulate the immune system and increase the general stress resistance of cobia larvae.

In this thesis an age structured model of fish and harvesting of fish are studied. This includes the basic properties as well as the analysis of equilibria and their stability for various recruitment functions. The only nonlinearity of this model lies in the juvenile stage in form of the recruitment function. Recruitment is considered as recruitment into the first year fertile class. The Ricker recruitment function will mostly be used . But we also discuss the Beverton-Holt recruitment and compare its impact. The main result is that monotone recruitment functions lead to a globally stable equilibrium. For Ricker recruitment functions periodic solutions are possible, but this model for cod and herring always leads to stable equilibria. Harvesting occurs in all classes separately with no harvesting in the first class. We describe harvesting in form of harvesting effort, resulting in an increase of mortality. This approach allows to model the interference of natural mortality and fishing mortality. Harvesting cost will be considered as a linear function of effort and the corresponding maxima are determined. This has the advantage to keep the number of parameters low. This makes the model more tractable and easier to apply to other stocks or species of fish. Optimization of the harvest is determined and analyzed. It is based on harvesting intensity and mesh size. We also show that harvesting increases stability of the static model. This model is extended to a discrete optimal control model in order to determine optimal sustainable policies. The solutions are almost of the fastest approach type to the equilibrium type solution. Periodic or pulse solutions do not arise. Near optimal strategies are analyzed and other feasible strategies are also considered. In last part of this thesis the problem of extinction of population is investigated. The effect of various factors as well as natural factors on marine fish populations are studied, which are described by the model in order to get some idea on the size of various factors. Most fishing takes place near the break even intensity. It is defined as the fishing mortality at which cost equals profit. As a further aspect recovery scenarios are studied. Concrete numerical studies for optimal solutions are determined for cod and herring. Care is taken to take into account all possible realistic parameters but also to keep the model tractable for other species.

Nanopartículas possuem características físico-químicas úteis para o uso humano, com aplicação na ciência, tecnologia, medicina e produtos de uso diário. A fabricação e a variedade destes produtos vêm crescendo rapidamente, gerando uma preocupação quanto ao risco de exposição aos efeitos tóxicos da contaminação por nanopartículas. Vários efeitos adversos, derivados da exposição de nanopartículas foram descritos tanto para organismos terrestres como aquáticos, porém efeitos genotóxicos ainda são pouco conhecidos para organismos marinhos. Para avaliar a citogenotoxicidade da nanopartícula de dióxido de titânio no peixe marinho T. carolinus, foram administradas injeções intraperitoneais com dosagens de 1,5 e 3,0 ?g-nano-TiO2/grama-de-peixe. Amostras de sangue foram coletadas para realização do teste de micronúcleo (MN) e outras anormalidades nucleares eritrocitárias (ANE) e ensaio cometa (pH>13), 24, 48 e 72 horas após a injeção. Foram investigadas a viabilidade de eritrócitos e a possibilidade de acumulação da nano-TiO2 nos tecidos dos peixes injetados com a maior dosagem, após 72 horas, pelo teste de exclusão do azul de tripano e por microscopia eletrônica de transmissão. Os resultados mostraram que a nano-TiO2 é uma substância possivelmente capaz de entrar nas células e induzir efeito genotóxico e citotóxico para esta espécie, por provocar uma diminuição na viabilidade de eritrócitos, um aumento no dano ao DNA e formação de MN e outras ANE. De acordo com nosso conhecimento, este é o único trabalho sobre a genotoxicidade de nano-TiO2 em um peixe marinho. / Nanoparticles have physicochemical characteristics useful for human use, with applications in science, technology, medicine and everyday products. The manufacture and variety of these products have been growing rapidly, creating a concern about the risk of exposure to the toxic effects of contamination by nanoparticles. Several adverse effects of exposure to nanoparticles have been reported for both terrestrial and aquatic organisms, but genotoxic effects are still poorly known for marine organisms. To evaluate the citogenotoxicity of titanium dioxide nanoparticles (nano-TiO2) in marine fish T. carolinus, the substance was administered with intraperitoneal injections at dosages of 1,5 and 3,0 ?g-nano-TiO2/gram-of-fish. Blood samples were collected for the tests of micronucleus (MN) and other erythrocytes nuclear abnormalities (ENA) and comet assay (pH> 13), 24, 48 and 72 hours after injection. We also investigated the viability of erythrocytes and the possibility of accumulation of nano-TiO2 in the tissues of fish injected with the highest dose after 72 hours using trypan blue exclusion test and transmission electron microscopy. The results showed that the nano-TiO2 is a substance that can possibly be able to enter cells and induce cytotoxic and genotoxic effect for this species, by causing a decrease in the viability of erythrocytes, an increase in DNA damage and formation of MN and other ANE. As far as we know, this is the only work done on the genotoxicity of nano-TiO2 in a marine fish

Nanopartículas possuem características físico-químicas úteis para o uso humano, com aplicação na ciência, tecnologia, medicina e produtos de uso diário. A fabricação e a variedade destes produtos vêm crescendo rapidamente, gerando uma preocupação quanto ao risco de exposição aos efeitos tóxicos da contaminação por nanopartículas. Vários efeitos adversos, derivados da exposição de nanopartículas foram descritos tanto para organismos terrestres como aquáticos, porém efeitos genotóxicos ainda são pouco conhecidos para organismos marinhos. Para avaliar a citogenotoxicidade da nanopartícula de dióxido de titânio no peixe marinho T. carolinus, foram administradas injeções intraperitoneais com dosagens de 1,5 e 3,0 ?g-nano-TiO2/grama-de-peixe. Amostras de sangue foram coletadas para realização do teste de micronúcleo (MN) e outras anormalidades nucleares eritrocitárias (ANE) e ensaio cometa (pH>13), 24, 48 e 72 horas após a injeção. Foram investigadas a viabilidade de eritrócitos e a possibilidade de acumulação da nano-TiO2 nos tecidos dos peixes injetados com a maior dosagem, após 72 horas, pelo teste de exclusão do azul de tripano e por microscopia eletrônica de transmissão. Os resultados mostraram que a nano-TiO2 é uma substância possivelmente capaz de entrar nas células e induzir efeito genotóxico e citotóxico para esta espécie, por provocar uma diminuição na viabilidade de eritrócitos, um aumento no dano ao DNA e formação de MN e outras ANE. De acordo com nosso conhecimento, este é o único trabalho sobre a genotoxicidade de nano-TiO2 em um peixe marinho. / Nanoparticles have physicochemical characteristics useful for human use, with applications in science, technology, medicine and everyday products. The manufacture and variety of these products have been growing rapidly, creating a concern about the risk of exposure to the toxic effects of contamination by nanoparticles. Several adverse effects of exposure to nanoparticles have been reported for both terrestrial and aquatic organisms, but genotoxic effects are still poorly known for marine organisms. To evaluate the citogenotoxicity of titanium dioxide nanoparticles (nano-TiO2) in marine fish T. carolinus, the substance was administered with intraperitoneal injections at dosages of 1,5 and 3,0 ?g-nano-TiO2/gram-of-fish. Blood samples were collected for the tests of micronucleus (MN) and other erythrocytes nuclear abnormalities (ENA) and comet assay (pH> 13), 24, 48 and 72 hours after injection. We also investigated the viability of erythrocytes and the possibility of accumulation of nano-TiO2 in the tissues of fish injected with the highest dose after 72 hours using trypan blue exclusion test and transmission electron microscopy. The results showed that the nano-TiO2 is a substance that can possibly be able to enter cells and induce cytotoxic and genotoxic effect for this species, by causing a decrease in the viability of erythrocytes, an increase in DNA damage and formation of MN and other ANE. As far as we know, this is the only work done on the genotoxicity of nano-TiO2 in a marine fish

Genes are the foundation of evolution and biodiversity. The genetic structure of natural populations needs to be understood to maintain exploited resources rationally. This thesis focuses on genetic variability and methods to determine spatial and temporal genetic heterogeneities. Intense human exploitation generates particular challenges to conserve genetic diversity of fishes since it has genetic effects. My research concerns one of our most valuable fish species: the Atlantic herring (Clupea harengus). I analyzed Atlantic herring samples from the North and Baltic Seas. The objectives were to determine: 1) spatial genetic structure, 2) whether allozymes and microsatellites provide similar descriptions of the differentiation pattern, or 3) if they are influenced by selection, 4) factors affecting statistical power when testing for genetic differentiation, and 5) the temporal stability of the genetic structure. The results show: 1) very low levels of spatial genetic differentiation in Atlantic herring; a major component is a difference between the Baltic and North Seas, 2) a concordant pattern with allozymes and microsatellites, 3) that selection influences a microsatellite locus, which can be a low salinity adaptation, 4) that statistical power is substantial for frequently used sample sizes and markers; the difference in power between organelle and nuclear loci is partly dependent on the populations’ stage of divergence, and 5) no changes in amount of genetic variation or spatial genetic structure over a 24-year period; the selection pattern in one microsatellite locus remained. The notion that the large population sizes make herring unlikely to lose genetic diversity may be disputed. I found small local effective population sizes, and the evidence of selection hints of a distinct evolutionary lineage in the Baltic. When Atlantic herring is managed as very large units, there can be detrimental genetic effects if certain population segments are excessively harvested.

To understand the processes affecting the abundance of wild populations is a fundamental goal of ecology and a prerequisite for the management of living resources. Variable abundance, however, makes the investigation of ecological processes challenging. Recruitment, the process whereby new individuals enter a given stage of a ?sh population, is a highly variable entity. I have confronted this issue by developing methodologies speci?cally designed to account for, and ecologically interpret, patterns of variability in recruitment. To provide the necessary context, Chapter 2 begins with a review of the history of recruitment science. I focus on the major achievements as well as present limitations, particularly regarding environmental drivers. Approaches that include explicit environmental information are contrasted with time-varying parameter techniques. In Chapter 3, I ask what patterns of variability in pre-recruit survival can tell us about the strength of density-dependent mortality. I provide methods to investigate the presence of density-dependent mortality where this has previously been hindered by highly variable data. Stochastic density-independent variability is found to be attenuated via density dependence. Sources of recruitment variability are further partitioned in Chapter 4. Using time-varying parameter techniques, signi?cant temporal variation in the annual reproductive rate is found to have occurred in many Atlantic cod populations. Multivariate state space models suggest that populations in close proximity typically have a shared response to environmental change whereas marked differences occur across latitude. Hypotheses that could result in consistent changes in productivity of cod populations are tested in Chapter 5. I focus on a meta-analytical investigation of potential interactions between Atlantic cod and small pelagic species, testing aspects of the cultivation-depensation hypothesis. The ?ndings suggest that predation or competition by herring and mackerel on egg and larval cod could delay recovery of depleted cod populations. Chapter 6 concludes with a critical re?ection on: the suitability of the theories employed, the underlying assumptions of the empirical approaches, and the quality of the data used in my thesis. Application of ecological insights to ?sheries management is critically evaluated. I then propose future work on recruitment processes based on methods presented herein.

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No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) Previous issue date: 2017-10-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Diapterus rhombeus is a fish of coastal and estuarine water that can be found throughout the Western Atlantic, from the Gulf of Mexico to Brazil. As it is a peidxe of great abundance it is important to have knowledge about the reproductive and parasitological biology of the species. With this, the objective of this study was to verify the main tactics that compose the reproductive strategy and the condition factor of D. rhombeus and the occurrence of isopod ectoparasites. The study was carried out in marine waters in the Northwest of the Atlantic Ocean (4º 50'57 ''S and 3751'36''W), more precisely in the coast of Areia Branca, RN, Brazil. A total of 298 individuals of the species were captured, in which in the study of their reproductive tactics it was identified that the individuals presented total weight ranges from 51.4g to 220.5g and a total length of 150mm to 245mm, where females were always found to be larger range of total length than males. In the analysis of weight and length both sexes presented a negative allometric growth, that is, the individuals had greater increase in length than in weight. Individuals presented a 1.8M: 1F sex ratio throughout the study. Four stages of gonadal maturation were identified macroscopically: immature, maturing, mature and emptied and microscopic study with histological analysis showed oocyte and sperm development within gonads at each stage of maturation. The length at which individuals entered first maturation was calculated to be 160 mm in total length. The gonadosomatic index (IGS) showed higher peaks for both males and females in November, December and January, indicating that the spawning season occurs soon after this period. The absolute fecundity was 16,313 oocytes and indicated that the females had a synchronous reproductive development in two groups. In the study of condition factor (K) higher peaks were shown shortly after the spawning season, indicating that the greater well-being of the individuals occurs in this period. The parasitic study showed that the species is parasitized by Cymothoa excisa, an isopod parasite that was found inhabiting the oral cavity of the individuals, presenting parasitic indexes with prevalence of 7.38%, mean intensity of 1.18 and average abundance of 0.09. In the present work, D. rhombeus individuals possess reproductive tactics that identify the species as a fish seasonal strategist and that the species can be considered as a new host of the C. excisa isotope ectoparasite / Diapterus rhombeus é um peixe de água costeira e estuarino que pode ser encontrado em todo Oeste do Atlântico, desde o Golfo do México até o Brasil. Como se trata de um peidxe de grande abundancia é importante ter o conhecimento sobre biologia reprodutiva e parasitológica da espécie. Com isso, o objetivo deste estudo foi verificar as principais táticas que compõem a estratégia reprodutiva e o fator de condição de D. rhombeus e a ocorrência de ectoparasitos isópodos. O estudo ocorreu em águas marinhas no Norte do Sudoeste do Oceano Atlântico (4º 50’57’’S e 3751’36’’O), mais precisamente no litoral de Areia Branca, RN, Brasil. Foram capturados 298 indivíduos da espécie, nos quais no estudo das suas táticas reprodutivas foi identificado que os indivíduos apresentaram amplitudes de peso total 51,4g a 220,5g e comprimento total de 150 mm a 245 mm, onde as fêmeas sempre foram encontradas em maior amplitude de comprimento total que os machos. Na análise de peso e comprimento ambos os sexos apresentaram um crescimento alométrico negativo, ou seja, os indivíduos tiveram maior incremento em comprimento que em peso. Os indivíduos apresentaram proporção sexual de 1,8M:1F ao longo do estudo. Quatro estádios de maturação gonadal foram identificados macroscopicamente: imaturos, em maturação, maduros e esvaziados e estudo microscópico com análise histológica mostrou o desenvolvimento ovocitário e espermático dentro das gônadas de cada estágio de maturação. O comprimento em que os indivíduos entraram em primeira maturação foi calculado como sendo em 160mm de comprimento total. O índice gonadossomático (IGS) apresentou picos mais elevados tanto para machos quanto para fêmeas nos meses de novembro, dezembro e janeiro, o que indicou que a época de desova ocorre logo após esse período. A fecundidade absoluta foi de 16.313 ovócitos e indicou que as fêmeas apresentam um desenvolvimento reprodutivo sincrônico em dois grupos. No estudo de fator de condição (K) foi mostrado picos mais elevados logo após a época de desova, indicando que o maior bem-estar dos indivíduos ocorre neste período. O estudo parasitário mostrou que a espécie se encontra parasitada por Cymothoa excisa, parasito isópodo que foi encontrado habitando a cavidade bucal dos indivíduos, apresentando índices parasitários com prevalência de 7,38%, intensidade média de 1,18 e abundancia média de 0,09. Registrando no presente trabalho que os indivíduos da espécie D. rhombeus possuem táticas reprodutivas que identificam a espécie como um peixe estrategista sazonal e que a espécie pode ser considerada como um novo hospedeiro do ectoparasito isópodo C. excisa / 2018-03-28

Made available in DSpace on 2014-06-11T19:22:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-06-05Bitstream added on 2014-06-13T18:08:11Z : No. of bitstreams: 1 rodrigues_vcs_me_jabo.pdf: 201320 bytes, checksum: 0b3a492d89a4de0571bff67b2f0754ed (MD5) / Com o intuito de conhecer o potencial zootécnico do pampo, foi avaliado o efeito de diferentes densidades de estocagem (100 e 200 peixes/m3) na sobrevivência e crescimento do pampo amarelo (Trachinotus carolinus), criado em tanque-rede instalado em ambiente marinho. Peixes com aproximadamente 1,0 a 2,0 g, capturados em arrastos nas praias rasas do município de Ubatuba, SP, foram transportados ao Núcleo de Pesquisa e Desenvolvimento do Litoral Norte - Agência Paulista Tecnológica do Agronegócio - Secretaria da Agricultura e Abastecimento e mantidos durante 45 dias em tanques-rede de 5mm de malhagem. Após seleção manual, animais de 4,0 ± 0,17g foram estocados, nas densidades de 100 e 200 peixes/m3, em tanques-rede de multifilamento com 2 x 2 x 1,5m e 12 mm de malhagem, fixos a um deck flutuante (6,0 x 8,0 m), instalado diretamente no mar a profundidade de aproximadamente 3,5 ± 0,5 m. Os animais foram alimentados duas vezes ao dia até a saciação com ração de 40% de PB. Após 120 dias, as taxas de sobrevivência média observadas foram 77,23% e 73,11 %; pesos médios (52,79 ± 4.86 9 e 52,64 ± 5.64 g); Ganho de Peso (GP) (48,69 ± 4,05 9 e 48,73 ± 4,00 g); Taxa de Crescimento Especifico (TCE) (2,13 ± 1,24 e 2,16 ± 1,03) e Conversão Alimentar Aparente (CAA) (3,23 ± 1,52 e 2,66 ± 0,78), respectivamente para 100 e 200 peixes/m3. Estes dados não apresentaram diferenças significativas (P~0,05) entre os tratamentos testados. Entretanto os ganhos de peso do pampo, no presente experimento foram superiores a muitos trabalhos encontrados na literatura, o que nos leva a concluir que a densidade de 200 peixes/m3, utilizada neste estudo, pode ainda estar abaixo da capacidade de suporte para a espécie e pode ser o ponto de partida para futuros estudos, considerando o estágio de desenvolvimento dos animais. / Aiming to know the zoothecnic potential of pampo, it was evaluated the effect of stocking densities (100 and 200 fish/m3) in the survival and growth rates of Florida pampano (Trachinotus carolinus), reared in marine cage. Fish with approximately 1 - 2g captured by seine in flat beaches of the city of Ubatuba, S.P. were transferred to the Núcleo de Pesquisa e Desenvolvimento do Litoral Norte - Agencia Paulista Tecnologica do Agronegocio - Secretaria Agricultura e Abastecimento and kept during 45 days in cage of 5mm mesh size. After manual selection, animals of 4.0 ± 0.17g had been stored, in the studied densities, cage of multifilament with 2 x 2 x 1.5 m and 12 mm of mesh size fixed to adeck (6.0 8.0 m), installed directly in the sea at a depth of approximately 3.5 ± 0.5 m. The animals had been fed twice¬-a day until satiation with ration of 40% of PB. Soon after a 120 days experimental period, the average survival rate (77.23% and 73.11 %); average body-weight (52.79 ± 4.86 and 52.64 ± 5.64); weiht gain (48.69 ± 4.05 and 48.73 ± 4.00); daily growth increment (2.13 ± 1.24 and 2.16±1.03) and apparent feed conversion rate (3.23 ± 1.52 and 2.66 ± 0.78), respectively for 100 and 200 fish/m3,were recorded. These parameters didn't present significant differences (P>=0,05) between the tested treatments. However pampo weight gain, in this experiment have been superior to many works found in literature, what allows the conclusion that pampo can be reaise in sea cages in densities above 200 fish/m3, and this density could be the starting point for future studies.