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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Aplicação de indicadores e índices para avaliar a sustentabilidade ambiental em um sistema de aquicultura integrado e multitrófico com diferentes substratos /

Proença, Danilo Cintra. January 2013 (has links)
Orientador: Wagner Cotroni Valenti / Banca: Iracy Lea Pecora / Banca: Mara Cristina Pessoa da Cruz / Resumo: A aquicultura é a atividade de produção de alimentos que mais cresce no mundo e tem sido criticada por seus impactos ambientais negativos. O caminho em direção da sustentabilidade é incerto e precisa ser avaliado. Foi utilizado um conjunto de indicadores para avaliar a sustentabilidade em um sistema de aquicultura integrado e multitrófico, usando espécie bentônica e nectônica combinadas com dois tipos de substratos. Um estudo de 5 meses foi realizado utilizando três diferentes tratamentos em um delineamento inteiramente casualizado: controle, sem substrato (WS); substrato manto geotêxtil (GS), e substratos de bambu (BS). Densidade de estocagem foi de 22 camarões m-2 e 1,1 tilápias m-2 para os tratamentos. As tilápias foram alimentadas com ração, aproximadamente 5-1% de sua biomassa, de acordo com a fase de desenvolvimento. A sustentabilidade ambiental foi medida com base na utilização de recursos naturais, a eficiência na utilização de recursos, a poluição liberada para o meio ambiente e o risco da espécie cultivada. Um índice de sustentabilidade ambiental foi criado a fim de avaliar qual o tratamento era mais sustentável. Os resultados mostraram que a GS melhorou a utilização dos recursos e BS a melhor eficiência da utilização dos recursos, além de melhorar a qualidade do sedimento. Apesar das vantagens da utilização de substrato, WS foi considerado o sistema mais sustentável. O uso de substratos não aumentou a sustentabilidade, devido principalmente a questão de emissão de gases / Abstract: Aquaculture is the food production activity that grows faster than any other in the world and has been criticized for its environmental negative impacts. The path toward sustainability requirements is uncertain and needs to be evaluated. We used a set of indicators to assess the sustainability of integrated aquaculture multispatial and multitrophic systems, using a benthonic and a nektonic omnivorous species combined with two types of substrates. A 5-month study was conducted using three different treatments in a completely randomized design: control, without substrate (WS); geotextile mantle substrate (GS); and bamboo substrate (BS). Stocking density was 22 prawns m-2 and 1.1 tilapias m-2 for all treatments. Tilapia was fed about 5-1% of their biomass, according to the development phase. Environmental sustainability was measured based on the use of natural resources, efficiency on the use of resources, pollution released to environment and risk of cultivated specie. An environmental sustainability index was created in order to evaluate which treatment was more sustainable. Results have shown that GS improved the use of resources and BS had the best efficiency of the use of resources and enhanced the sediment quality. Despite of the advantages of using substrate, WS was considered the most sustainable system. The use of substrates did not increase the sustainability due mainly to gas emission issue / Mestre
12

Diferenciação morfotípica de machos de camarão de água doce Macrobrachium amazonicum (Heller, 1862) (Crustacea, Decapoda, Palaemonidae) /

Moraes-Riodades, Patrícia Maria Contente. January 2002 (has links)
Orientador: Wagner Cotroni Valenti / Banca: Gilson Luiz Volpato / Banca: Julio Vicente Lombardi / Resumo: Esse trabalho teve como objetivo verificar a possível existência de morfotipos em machos de M. amazonicum e definir as características para a sua identificação. Animais provenientres de viveiros de cultivo de todas as classes de tamanho foram analisados quanto a cor e espinação do segundo quelípodo direito. A seguir, foram medidos para determinação dos comprimentos total, pós-orbital, da carapaça, do quelípodo direito e dos cinco artículos que o compõem. As relações entre essas dimensões foram determinadas, utilizando-se técnicas para estudos de crescimento relativo. O trabalho mostrou que a população de M. amazonicum é composta por quatro grupos distintos, que diferem na morfologia dos quelípodos e em várias relações morfométricas. Isto confirma a hipótese da existência de morfotipos nessa espécie. Pode-se, portanto definir quatro morfotipos, que foram chamados "Translucent Claw" (TC), "Cinnamon Claw" (CC), "Green Claw" (GC) e "Green Claw linha" (GC'). Os machos TC são pequenos, apresentam o quelípodo translúcido, geralmente sem espinhos, providos ou não de botões (espinhos em formação), ou com espinhos pequenos formando um ângulo £ 60º. O morfotipo CC é constituído por animais com tamanho similar a TC, com a coloração tendendo a cor de canela e espinhos do quelípodo formando ângulo £ 60º. Os machos GC constituem um grupo de animais de grande porte em relação a TC e CC, com quelípodos desenvolvidos e maiores que o comprimento pós-orbital. Estes apresentam coloração verdemusgo, com espinhos em inclinação variando entre 60º e 90º. Os camarões que constituem o morfotipo GC' apresentam características semelhantes ao grupo GC em cor e espinação, mas o comprimento do quelípodo é proporcionalmente menor, sendo inferior ao comprimento pósorbital. A identificação de cada casta de machos de M. amazonicum possibilitará o prosseguimento de... / Abstract: The aim of this paper was to investigate the morphotypic differentiation of Macrobrachium amazonicum male. A key for identification of these morphotypes was provided using observations on color and spination of chelipeds supplemented by relative growth techniques. Prawns were taken from nine earthen ponds at Jaboticabal, São Paulo, Brazil. Total length, post-orbital length and the length of carapace, chelipeds and all limb joints were measured on the right second pereiopod with a vernier caliper. Four distinct morphotypes were identified, "Translucent Claw" (TC), "Cinnamon Claw" (CC), "Green Claw" (GC) and "Green Claw apostrophe" (GC' ). They differ by chelipeds morphology and several morphometric relationships. TC prawns are small in size and present chelipeds translucent with tubercles or spines, which point distally at an angle £ 60º. CC males are similar to TC in size and spination, but present cinnamon chelipeds. GC and GC' are large prawns with long dark green chelipeds provided with long and robust spines, which point distally at an angle ranging between 60º and 90º. They differ only by chelipeds proportion. GC cheliped length overtake post-orbital length while the opposite occurs in GC' males. Recognition of morphotypes will be useful for future biology and culture works aiming increase pond production of M. amazonicum / Mestre
13

Utilização de diferentes dietas na larvicultura do camarão pitu, Macrobrachium carcinus (Linnaeus, 1758)

SANTOS, Edson Pereira dos 28 April 2006 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-09T16:26:01Z No. of bitstreams: 1 Edson Pereira dos Santos.pdf: 1722361 bytes, checksum: a0364ce831329e35264c970b58fe0613 (MD5) / Made available in DSpace on 2017-02-09T16:26:01Z (GMT). No. of bitstreams: 1 Edson Pereira dos Santos.pdf: 1722361 bytes, checksum: a0364ce831329e35264c970b58fe0613 (MD5) Previous issue date: 2006-04-28 / The freshwater prawn Macrobrachium carcinus production had been commercially explored in several countries. In northeast, the prawn fishery has a great importance in Low São Francisco Basin. The large scale postlarvae production continues being the main problem for commercial culture and natural stocks maintenance. This work aimed to test different diets in Macrobrachium carcinus larval culture in order to improve the performance of prawn post-larvae production, with the utilization of fish flesh (Ff) and a formulated diet (Fd), or in association with adult artemia biomass (FfB and FdB, respectively), resulting in four treatments and six replicates. Were used twenty-four 20 L circular recipients provided of water recirculating and aeration systems, where were stocked 25 larvae (zoea V-VI) per liter. The diets were offered four times a day (07:00, 10:00, 13:00 and 16:00 hrs) during 49 days. Water temperature was 27.5±1.2ºC in the morning and 28.4±1.3ºC in the afternoon; the total ammonia nitrogen and nitrite were 0.2±0.2 and 0.5±0.8 mg/L, respectively, while pH and salinity maintained around 8.2 and 24, respectively. The average larval survival was 3.47±1.56, 7.40±2.99, 14.83±2.64 and 7.57±2.31, respectively for Ff, FfB, Fd and FdB treatments. Ff treatment obtained the lowest survival due to larvae reject by the fish flesh. Fdand FdB treatments showed significant difference (P≤0.05), with better survival obtained by FdB diet. The highest survival was obtained by the Fd diet (14.83%), that showed itself as the more appropriated alternative to use in M. carcinus hatchery, but the adult artemia biomass showed that could provide better survival rates when associated with other feeds. / A produção do camarão pitu Macrobrachium carcinus tem sido explorada comercialmente em diversos países. No Nordeste, a pesca do pitu é de grande importância no Baixo São Francisco. A produção em larga escala de pós-larvas do pitu continua sendo o principal empecilho para o cultivo comercial e recuperação dos estoques naturais. Desta forma, objetivou-se com o presente trabalho testar diferentes dietas na larvicultura de M. carcinus, visando melhorar o desempenho da produção de pós-larvas, com a utilização de músculo de peixe (Dp) e uma dieta formulada (Df), ou em associação à biomassa de Artemia sp (DpB e DfB, respectivamente), perfazendo quatro tratamentos em seis réplicas. Utilizaram-se 24 recipientes circulares de 20 L com sistemas de recirculação de água e aeração, nos quais estocaram-se 25 larvas (zoea V-VI) por litro. As dietas foram ofertadas em quatro horários (07:00, 10:00, 13:00 e 16:00h) durante 49 dias. Durante o cultivo registrou-se valores médios de 27,5 ± 1,2 ºC (manhã) e 28,4 ± 1,3 ºC (tarde) para temperatura, de 0,2 ± 0,2 mg/L para amônia total e de 0,5 ± 0,8 mg/L para nitrito, enquanto que o pH e a salinidade mantiveram-se em 8,2 e 24‰, respectivamente. Os percentuais de sobrevivência média das larvas foram 3,47 ± 1,56, 7,40 ± 2,99, 14,83 ± 2,64 e 7,57 ± 2,31%, respectivamente, para os tratamentos Dp,DpB, Df e DfB. No tratamento Dp obteve-se a menor (P≤0,05) sobrevivência, pelo fato das larvas rejeitarem o músculo de peixe triturado. As dietas Dp e DpB apresentaram diferença significativa (P≤0,05), com maior sobrevivência para a dieta DpB. A maior sobrevivência foi obtida pela dieta Df (14,83%), que se apresentou como a alternativa mais apropriada para a utilização na larvicultura de M. carcinus, entretanto a biomassa de artêmia adulta mostrou que poderá resultar em uma melhoria na taxa de sobrevivência quando associada com outros alimentos.
14

Construção de uma biblioteca genômica de DNA para o camarão pitu Macrobrachium carcinus (Linnaeus, 1758), enriquecida para microssatélite

NOGUEIRA, Marcus Vinícius da Fonseca 23 February 2011 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-16T13:16:29Z No. of bitstreams: 1 Marcus Vinicius da Fonseca Nogueira.pdf: 638685 bytes, checksum: d13ddfd4141db61372cb422de3cd12cf (MD5) / Made available in DSpace on 2017-02-16T13:16:29Z (GMT). No. of bitstreams: 1 Marcus Vinicius da Fonseca Nogueira.pdf: 638685 bytes, checksum: d13ddfd4141db61372cb422de3cd12cf (MD5) Previous issue date: 2011-02-23 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The painted river prawn (Macrobrachium carcinus), occurs from Florida state (USA) to south Brazil. It is included in the red list of endangered species of the Brazilian Environmental Ministry. Restocking Programs have been used in the recovery of freshwater stocks. Such programs need to attend certain principles in order to assure that genetic diversity will be preserved. The knowledge on wild diversity and genetic structures is essential information to guide restocking activities. Microsatellite markers are frequently used to describe genetic structure because they are codominant, highly polymorphic and, selectively neutral. Total DNA was extracted, digested with RsaI enzyme, purified, dephosphorylated, and ligated to double-stranded linkers amplified via PCR. Hybridization used biotinylated probes for tetranucleotide (GACA)4 and (GATA)7 and trinucleotide mix (ATT)8, (CTT)8 and(GGT)8 motifs. DNA was linked into a cloning vector and transformed into competent cells Escherichia coli. A total of 358 clones were generated, being 237 positive clones, of which 161 were sequenced. Repetitive di (32), tri (7) and tetra (27) nucleotide were obtained and primers were designed using Primer3 software. Among optimized loci, six are monomorphic and 26 polymorphic. Most abundant repetitions are di (GA) n=14 and (TC) n=10, followed by tetra repetitions (GACA) n=8 and (TCGT) n=8, and (CTGT) n=7. A high number of tetranucleotides repeats are advantageous, since they can facilitate the process of allele discrimination, especially in poliacrylamide gel electrophoresis. / O camarão de água doce pitu (Macrobrachium carcinus ocorre desde o estado da Flórida (EUA) até a região Sul do Brasil. A espécie está inserida na lista vermelha de espécies ameaçadas de extinção do Ministério do Meio Ambiente. Programas de repovoamento constituem uma prática comum na recuperação de estoques, especialmente em águas continentais. Esses programas precisam atender a certos princípios, para assegurar que a diversidade genética seja preservada. O conhecimento da diversidade e estrutura genéticas de populações selvagens é uma informação essencial para subsidiar atividades de repovoamento. Marcadores moleculares de microssatélite são freqüentemente usados para descrever a estrutura genética por serem altamente polimórficos, codominantes e seletivamente neutros. DNA total do camarão pitu foi extraído, digerido com a enzima RsaI, purificado, desfosforilado, ligado a adaptadores e amplificados via reação em cadeia da polimerase (PCR). A hibridização foi feita com sondas biotiniladas para motivos tetranucleotídicos, tais como (GACA)4 e (GATA)7 e um mix de trinucleotídeos, (ATT)8, (CTT)8, (GGT)8. O DNA foi então ligado a um vetor de clonagem e transformado em células competentes de Escherichia coli. Um total de 358 clones foi gerado, dentre os quais 237 foram positivos, sendo 121 deles sequenciados. Repetições do tipo di(32), tri(7) e tetra(27) núcleotídicas foram obtidas, a partir dos quais primers foram construídos, usando o programa Primer3. Dentre os marcadores otimizados para amplificação, seis apresentaram-se monomórficos e 26 polimórficos. A maior parte das repetições foi do tipo (GA) n=14 e (TC) n=10, seguidas de motivos tetra, (GACA) n=8, (TCGT) n=8 e (CTGT) n=7. O alto número de repetições tetranucleotídicas é extremamente vantajoso por facilitar o processo de discriminação de alelos, especialmente em eletroforese de gel de poliacrilamida.
15

The Effect of Temperature on Phenotypes of the Invasive European Green Crab: Physiologic Mechanisms that Facilitate Invasion Success

Kelley, Amanda 29 May 2013 (has links)
Invasion physiology is an emerging field that endeavors to understand the influence of physiological traits on the establishment of non-native species in novel environments. The invasive European green crab,Carcinus maenas, is one of the world's most successful aquatic invaders, and is currently distributed across temperate marine ecosystems globally. The work presented here explored the thermal physiology of this species, and has highlighted several physiological traits that have likely influenced establishment success. Intraspecific comparisons of crabs sampled from the northern and southern edges of their recipient, or invaded range on the west coast of North America have identified both organismal and cellular physiological difference with respect to upper and lower thermal tolerances. Crabs sampled from British Columbia, Canada (BC) had a significantly lower mean upper thermal tolerance threshold and heat shock protein synthesis, Hsp70, compared to their warm acclimated conspecifics sampled from California (CA). These differential physiologic responses may be rooted in the disparate natural thermal habitats that each population occupies within their respective environments. The ability of this species to extend its current range limits was also investigated. Range expansion to the south has been limited, and is likely restricted by this species lack of adaptation to warmer temperatures. Because range expansion has been chiefly northward, characterizing this species' response to cold stress can identify whether colder temperatures poleward may limit further range expansion. Cold tolerance capacity was determined in the laboratory, and crabs sampled from Vancouver Island, British Columbia were able to withstand the over-wintering thermal regime that occurs in Sitka, Alaska, a site that is currently beyond the range limits of this species. Furthermore, intraspecific assessments found that the cold acclimated BC population exposed to cold shock significantly down regulated protein levels of cyclin D1, cell cycle modulator. Distinct differences in carapace width (CW) were detected along the thermal gradient present in the green crabs' range. This variation in body size was utilized to the test the temperature size rule hypothesis for ectotherms. Simply stated, the temperature size rule is the tendency for ectotherms to develop slower but mature to a larger body sizes at cooler temperatures. The results supported this hypothesis as crabs sampled from the warm portion of the range were found to be smaller than crabs sampled from the colder portion of the range. This pattern was detected along the native range as well. Differences in body size have the potential to influence the scope of invasion; larger individuals are generally more fecund and longer lived, which can increase both the intensity and frequency of larval dispersal that could further propel range expansion. The physiologic properties that the green crab possesses which may influence invasion success were examined using peer-reviewed literature with the aim of determining if these physiological traits confer invasion success across taxa. This analysis tested four hypotheses: 1) Broad geographic temperature tolerances (thermal width) confer a higher upper thermal tolerance threshold when comparing invasive and native species. 2) The upper thermal extreme experienced in nature is correlated with upper thermal tolerance threshold. 3) Protein chaperone expression, a cellular mechanism underlying thermal tolerance threshold, is greater in invasive organisms than in native ones. 4) Acclimation to higher temperatures can promote a greater range of thermal tolerance for invasives compared to natives. These preliminary results generally support the four stated hypotheses, and provide a solid foundation for further studies to explore and identify physiologic traits that facilitate invasion success. Overall, these studies investigated the thermal physiology ofCarcinus maenasfrom an invasive metapopulation and have brought about significant advances in our understanding of what physiologic traits correlate to invasion success in this species. In addition, the data presented here can aid resource managers in identifying habitats, based on thermal tolerance measurements that fit the criteria for invasion. Understanding how invasive organisms vary with respect to thermal tolerance can aid our understanding the patterns and processes of species invasions.
16

Generating genomic resources for two crustacean species and their application to the study of White Spot Disease

Verbruggen, Bas January 2016 (has links)
Over the last decades the crustacean aquaculture sector has been steadily growing, in order to meet global demands for its products. A major hurdle for further growth of the industry is the prevalence of viral disease epidemics that are facilitated by the intense culture conditions. A devastating virus impacting on the sector is the White Spot Syndrome Virus (WSSV), responsible for over US $10 billion in losses in shrimp production and trade. The Pathogenicity of WSSV is high, reaching 100 % mortality within 3-10 days in penaeid shrimps. In contrast, the European shore crab Carcinus maenas has been shown to be relatively resistant to WSSV. Uncovering the basis of this resistance could help inform on the development of strategies to mitigate the WSSV threat. C. maenas has been used widely in studies on ecotoxicology and host-pathogen interactions. However, like most aquatic crustaceans, the genomic resources available for this species are limited, impairing experimentation. Therefore, to facilitate interpretations of the exposure studies, we first produced a C. maenas transcriptome and genome scaffold assembly. We also produced a transcriptome for the European lobster (Homarus gammarus), an ecologically and commercially important crustacean species in United Kingdom waters, for use in comparing WSSV responses in this, a susceptible species, and C. maenas. For the C. maenas transcriptome assembly we isolated and pooled RNA from twelve different tissues and sequenced RNA on an Illumina HiSeq 2500 platform. After de novo assembly a transcriptome encompassing 212,427 transcripts was produced. Similar, the H. gammarus transcriptome was based on RNA from nine tissues and contained 106,498 transcripts. The transcripts were filtered and annotated using a variety of tools (including BLAST, MEGAN and RSEM) and databases (including GenBank, Gene Ontology and KEGG). The annotation rate for transcripts in both transcriptomes was around 20-25 % which appears to be common for aquatic crustacean species, as a result of the lack of well annotated gene sequences for this clade. Since it is likely that the host immune system would play an important role in WSSV infection we characterized the IMD, JAK/STAT, Toll-like receptor and other innate immune system pathways. We found a strong overlap between the immune system pathways in C. maenas and H. gammarus. In addition we investigated the sequence diversity of known WSSV interacting proteins amongst susceptible penaeid shrimp/lobster and the more resistant C. maenas. There were differences in viral receptor sequences, like Rab7, that correlate with a less efficient infection by WSSV. To produce the genome scaffold assembly for C. maenas we isolated DNA from muscle tissue and produced both paired-end and mate pair libraries for processing on the Illumina HiSeq 2500 platform. A de novo draft genome assembly consisting of 338,980 scaffolds and covering 362 Mb (36 % of estimated genome size) was produced, using SOAP-denovo2 coupled with the BESST scaffolding system. The generated assembly was highly fragmented due to the presence of repetitive areas in the C. maenas genome. Using a combination of ab initio predictors, RNA-sequencing data from the transcriptome datasets and curated C. maenas sequences we produced a model encompassing 10,355 genes. The gene model for C. maenas Dscam, a gene potentially involved in (pan)crustacean immune memory, was investigated in greater detail as manual curation can improve on the results of ab initio predictors. The scaffold containing C. maenas Dscam was fragmented, thus only contained the latter exons of the gene. The assembled draft genome and transcriptomes for C. maenas and H. gammarus are valuable molecular resources for studies involving these and other aquatic crustacean species. To uncover the basis of their resistance to WSSV, we infected C. maenas with WSSV and measured mRNA and miRNA expression for 7 time points spread over a period of 28 days, using RNA-Seq and miRNA-Seq. The resistance of C. maenas to WSSV infection was confirmed by the fact that no mortalities occurred. In these animals replicating WSSV was latent and detected only after 7 days, and this occurred in five of out 28 infected crabs only. Differential expression of transcripts and miRNAs were identified for each time point. In the first 12 hours post exposure we observed decreased expression of important regulators in endocytosis. Since it is established that WSSV enters the host cells through endocytosis and that interactions between the viral protein VP28 and Rab7 are important in successful infection, it is likely that changes in this process could impact WSSV infection success. Additionally we observed an increased expression of transcripts involved in RNA interference pathways across many time points, indicating a longer term response to initial viral exposure. miRNA sequencing showed several miRNAs that were differentially expressed. The most striking finding was a novel C. maenas miRNA that we found to be significantly downregulated in every WSSV infected individual, suggesting that it may play an important role in mediating the response of the host to the virus. In silico target prediction pointed to the involvement of this miRNA in endocytosis regulation. Taken together we hypothesize that C. maenas resistance to WSSV involves obstruction of viral entry by endocytosis, a process probably regulated through miRNAs, resulting in inefficient uptake of virions.
17

Ciclo de muda e metabolismo durante o desenvolvimento larval do camarão-da-amazônia Macrobrachium amazonicum (Heller, 1862) /

Hayd, Liliam de Arruda. January 2007 (has links)
Resumo: O estudo teve por objetivo descrever o ciclo de muda e estudar o metabolismo nas fases iniciais do desenvolvimento ontogenético de Macrobrachium amazonicum. O trabalho está organizado em cinco capítulos. O capítulo 1 apresenta uma introdução geral, apresentando os estudos inerentes à M. amazonicum e o programa de tecnologia onde este estudo esta inserido. No capítulo 2 estão descritos os estágios do ciclo de muda de M. amazonicum. As descrições foram determinadas e documentadas fotograficamente em intervalos diários usando o telson como principal região de referência e aplicando o sistema de classificação de Drach, observando as principais mudanças que ocorrem na epiderme e na cutícula. O desenvolvimento é rápido (1-2 dias ou 2-4 dias por instar larval a 29 e 21°C, respectivamente). Foram descritos os seguintes estágios de muda, A/C (pós-muda/intermuda combinados), D (pré-muda) e E (ecdise). Estima-se que a pós-muda/intermuda (A/C) ocupe cerca de 40-50% do total de duração do instar enquanto que o período da pré-muda (D) requer mais que a metade do tempo nas temperaturas experimentais. O capítulo 3 apresenta a descrição do metabolismo de embriões, larvas e pós-larvas (PL com 1, 7 e 14 dias após a metamorfose) nas fases iniciais do desenvolvimento ontogenético. O peso seco, consumo de oxigênio, excreção de amônia total-N e taxa atômica O:N foram determinados. Os animais em estágio de muda A/C foram separados conforme o estágio de desenvolvimento larval e colocados dentro de câmaras respirométricas (30mL) por 2h para quantificar as taxas metabólicas. Após este período, as amostras foram analisadas pela titulação de Winkler e método de Koroleff para o consumo de oxigênio e nitrogênio amoniacal, respectivamente. As taxas metabólicas foram expressas como taxas individuais e peso-específico ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The moulting cycle was studied in laboratory-reared larvae of the Amazon River prawn, Macrobrachium amazonicum. Using the telson as main reference region and applying Drach's classification system, we checked twice daily the epidermis and cuticle and documented major structural changes such as the retraction of epidermal tissues from the cuticle and setal development. Rapid development (1-2d or 3-4d per larval instar at 29 and 21°C, respectively), a thin and little structured larval integument, and gradual rather than abrupt integumental changes allowed for only a coarse classification of the moulting cycle with three principal stages, A-C (postmoult and intermoult stages combined), D (premoult), and E (ecdysis). These periods could be morphologically further divided into substages; however, without providing a definite timing for their transitions. At early postmoult (stage A), the cuticle is still thin and water is taken up, so that the larval body expands and rapidly attains its final size and shape. The epidermal tissues reveal at this stage a spongy structure with numerous lacunae. During later postmoult (stage B) and throughout intermoult (stage C), the larvae reinforce the cuticle, while the epidermis shows an increasing condensation with reduced lacunar spaces and conspicuous tissue growth. Early premoult (substage D0) begins with a retraction of the epidermis from the cuticle (apolysis), which is first visible at the setal bases. During intermediate premoult (substage D1), epidermal invaginations take place, leading to a substantial enlargement of the epidermal surface and initiating the formation of new setae and appendages (setogenesis, morphogenesis). Subsequently, a thin new cuticle is secreted on the epidermal surface (substages D2-4). Moulting (stage E) is a very short process, which usually takes only a few minutes ...(Complete abstract, click electronic access below) / Orientador: Wagner Cotroni Valenti / Coorientador: Daniel Lemos / Banca: Maria Célia Portella / Banca: Margarete Mallasen / Banca: Francisco de Assis Leone / Banca: Laura Satiko Okada Nakaghi / Doutor
18

Avaliação do frescor e vida útil do camarão de água doce, Macrobrachium rosenbergii, armazenado em gelo /

Kirschnik, Peter Gaberz. January 2003 (has links)
Orientador: Elisabete Maria Macedo Viegas / Banca: Wagner Cotroni Valenti / Banca: Rose Meire Vidotti / Resumo: Este trabalho teve como objetivo avaliar a vida útil do camarão de água doce Macrobrachium rosenbergii armazenado descabeçado em gelo durante 14 dias, comparando duas condições de armazenamento: CCG - camarões armazenados em contato direto com o gelo e SCG - sem contato com gelo (camarões em sacos plásticos mantidos em gelo). A vida útil foi monitorada por meio de análises químicas como nitrogênio não protéico (NNP), bases nitrogenadas voláteis (BNV), TBA, determinação do pH, e também por análises microbiológicas e sensoriais. Foram realizadas amostragens em intervalos de tempo aos 0, 2, 4, 7, 10 e 14 dias de estocagem. Os teores iniciais de BNV de 18,75 mg de N/100g de amostra atingiram 21,73 mg N/100g no tratamento SCG e 5,47 mg de N/100g no tratamento CCG após 14 dias de estocagem. Os teores de NNP para o tratamento SCG aumentaram de 436,99 mg de N/100g no dia zero para 542,30 mg de N/100g no final do armazenamento. No tratamento CCG, os teores de NNP diminuíram até o final do experimento (436,99 a 158,24 mg de N/100g). Os valores de TBA aumentaram no tratamento SCG ao longo da estocagem (0,08 a 1,83 mg de malonaldeído/kg) e mantiveram-se constantes no tratamento CCG (0,08 mg de malonaldeído/kg para 0,18 mg de malonaldeído/kg). Os dois tratamentos tiveram o mesmo comportamento quanto ao pH, mantendo-se constantes durante toda a estocagem. As contagens de coliformes fecais e totais mantiveram-se dentro dos níveis de aceitação em ambos os tratamentos. A contagem inicial de psicrotróficos foi de log 2,32 UFC/g para os dois experimentos, verificando-se, posteriormente um aumento de cerca de duas casas logarítmicas para o tratamento SCG e três unidades logarítmicas por grama de tecido para o tratamento CCG. Na análise sensorial os provadores não constataram alterações de sabor até o 10o dia de estocagem, nos camarões do tratamento SCG, detectando porém queda... / Abstract: The objective of the present work was to evaluate the shelf-life of the freshwater prawn Macrobrachium rosenbergii deheaded, shelled and stored in ice during 14 days. Two storage conditions were compared: DIC - prawn storage with direct ice contact and WIC - prawns without ice contact (specimens packed in polyethylene bags). The shelflife was evaluated by chemical analysis, namely: non-protein nitrogen (NPN), total volatile base nitrogen (TVB-N), rancidity (TBA), pH; and also by microbiological and sensorial analysis. Samples were collected at 0, 2, 4, 7, 10, and 14 days of storage. TVB-N initial contents (18.75 mg N/100g sample) reached 21.73 mg N/100g in WIC treatment and 5.47 mg N/100g in DIC treatment after 14 days of storage. NNP contents in WIC treatment increased from 436.99 mg N/100g at day zero to 542.30 mg N/100g in the end of storage. In DIC treatment, NNP contents decreased until the last day of this study (from 436.99 to 158.24 mg N/100g). TBA values increased in WIC treatment along of storage (from 0.08 to 1.83 mg of malonaldehyde/kg) and remained approximately constant in DIC treatment (from 0.08 mg to 0.18 of malonaldehyde/kg). Also for both treatments the pH was observed to remain constant during the whole storage time. Total and faecal coliforms countings were within the acceptable levels in both treatments. The initial psychrotrophic counting scored log 2.32 CFU/g for both experiments; at the end of the storage we observed an increase of about two logarithmic units/g for WIC treatment and of three logarithmic units/g for DIC treatment. Regarding the sensorial analysis, the assessors observed no changes in flavour until the 10th storage day for prawns in WIC treatment. At the 14th day, a decrease in quality (P < 0.05) was detected. In DIC treatment, however, flavour scores continuously decreased (P < 0.05) during the storage, reaching an average value of 4 in a scale from ... / Mestre
19

Análise da produtividade e viabilidade econômica de quatro sistemas de berçários do camarão-da-Amazônia, Macrobrachium amazonicum /

Penteado, José Mario de Aquino. January 2012 (has links)
Orientador: Wagner Cotroni Valenti / Banca: Helenice Pereira de Barros / Banca: Sergio Ricardo Batlouni / Resumo: O objetivo desse trabalho foi avaliar quatro sistemas de berçários, em termos técnicos e econômicos, para a produção de juvenis de Macrobrachium amazonicum, e discutir suas possíveis vantagens, limitações e aplicações para a realização de monocultivos e sistemas integrados de produção do camarão-da-amazônia, que objetivam vender sua produção para consumo ou como iscas e para lojas de animais ornamentais. Os sistemas avaliados foram: tanques internos com recirculação de água (BTI), tanques cobertos com estufa plástica - "greenhouse" (BTCP), viveiros de Fundo Natural (BVFN) e tanques-rede (BTR). Os tratamentos BVFN e BTCP condicionaram os maiores valores de massa úmida final (0.80 ± 0.13 e 0.67 ± 0.15 g, respectivamente), massa seca final (0.25 ± 0.05 e 0.21 ± 0.06 g) e ganho de massa individual dos camarões (0.79 ± 0.13 e 0.66 ± 0.15 g). Sobrevivência e produtividade não diferiram estatisticamente entre os tratamentos. Para a análise econômica de cada sistema, foi realizada uma simulação, considerando-se fazendas comerciais produzindo juvenis de M. amazonicum de acordo com as condições e sobrevivências obtidas experimentalmente em cada sistema. Foram realizadas análises de custo-retorno, fluxo de caixa e determinação de indicadores de rentabilidade calculados na forma tradicional, ou seja: Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Período de Retorno de Capital (PRC) e Relação Benefício Custo (RBC). Variações de cenários econômicos (preço de venda, custo de ração e sobrevivência) em cada berçário, também foram estudadas. Apenas as fazendas em sistema BVFN e BTR apresentaram viabilidade econômica, após essas análises. Os quatro sistemas de berçário apresentaram bons resultados zootécnicos, no entanto todos eles encarecem muito a produção de animais para a fase... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate four nursery systems, in technical and economical aspects, for the production of juveniles of Macrobrachium amazonicum in four nursery systems, and discuss their possible advantages, limitations and possible applications for monoculture and integrated systems for production of Amazon river prawn, who aim to sell their production for food or as live bait and ornamental animals. The systems are: indoor tanks with water recirculation (BTI), greenhouse system (BTCP), earthen ponds (BVFN) and net cages (BTR), during the warm season in places with subtropical climate. BTCP and BVFN had the highest final wet mass (0.80 ± 0.13 e 0.67 ± 0.15 g, respectively), final dry mass (0.25 ± 0.05 e 0.21 ± 0.06 g) and individual mass gain (0.79 ± 0.13 e 0.66 ± 0.15 g). Survival and productivity didn't differ amongst treatments. For economical analysis of each system, we made a simulation considering commercial farms producing M. amazonicum juveniles according to conditions and productivity experimentally obtained in each system. It was performed analysis of cost-return, cashflow and the determination of indicators of rentability calculated in traditional way, such as: net present value (VPL), internal return rate (TIR), payback period (PB) and benefit cost ratio (RBC). Variations of economic scenarios (selling price, food cost and survival) in each nursery also were studied. Only BVFN and BTR farms reached economical viability after these analisys. The four systems showed good results related to production. However, all of them made the final grow-out phase expensive. The use of these nurseries is only justified in case of maintaining the post-larvae in the winter in those systems... (Complete abstract click electronic access below) / Mestre
20

The Proteomic Response of the Carcinus maenas Y-organ Over the Course of the Molt Cycle

Hamer, Mark S 01 February 2015 (has links) (PDF)
Molting in arthropods is a complex process governed by regulatory mechanisms that have evolved and adapted over millennia to allow these animals to grow, despite being confined by a hardened exoskeleton. We isolated the molt-regulating Y-organs (YO) from the common shore crab Carcinus maenas at molt stages B, C1-3, C4, and D0 to assess how changes in protein abundances might underline the unique physiology of each of these stages. We found that changes in protein abundance were most notable in the postmolt stages (B and C1-3), where an increase in energy metabolism and the reactive oxygen species stress (ROS) response proteins was observed. An increase in triosephosphate isomerase and transketolase suggest that the postmolt YO is participating in triglycerides storage and is also actively recycling excess ribose sugars manufactured during the YO’s previously activated state. We also propose as mechanism through which ROS-induced release of cyclophilin A may contribute to YO atrophy during postmolt through the remodeling of structural proteins such as collagen. We support the standing observation of YO atrophy during postmolt by drawing attention to hemolymph protein abundances, especially those of cryptocyanin isoforms, which dropped precipitously in intermolt (C4) and remained at low abundances into early premolt (D0). Finally, though our evidence is preliminary, we propose that future investigations into the YO proteome address the significance of the protein glutamate dehydrogenase. Glutamate dehydrogenase, a key enzyme involved in the formation of glutamate, represents a potential nutrient-sensing checkpoint that might be involved in YO activation. Historically, most attention has gone to the acute molt stages, where signaling mechanisms involved in the activation of the YO have been the focus. Here, we present data suggesting that other regulatory mechanism may be governing the atrophy the postmolt YO. A better understanding of crustacean physiology has the potential to benefit ecosystems and economies worldwide.

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