Navegando por Assunto "Ostra"

Agora exibindo 1 - 5 de 5

Acesso aberto (Open Access)
Avaliação e comparação de projetos comunitários de ostreicultura localizados no nordeste paraense
(Universidade Federal do Pará, 2009) HOSHINO, Priscila; MCGRATH, David Gibbs; http://lattes.cnpq.br/4373475491613670
The aquaculture is being characterized as strategy to minimize the reduction of the fish. At Pará, the oyster farming was implanted in 2003 as an opportunity regarding to occupation and profits generation at Northeastern of this state. In 2005 this initiative was expanded to other communities with different levels of familiarity with the mollusk, regarding to the support either on the researches in this sector or on the extractive activity. This research evaluated the communitarian oyster farming performance in the state of Pará. It was studied three projects with at least two years of implementation and with either different levels of preservation and oyster harvest activity. The implementation of the firsts cultivations occurred simultaneously and in a similar way regarding to institutional support, however with different performances. The main producer issues are to obtain the license to develop this activity and also the necessity to take care about the tide. It is necessary to provide more detailed feasibility studies, with more commitment from the side of the interested institutions in order to perform the actions they are supposed to work out, providing events where it will be possible to spread the information and discuss the aquaculture bottlenecks at the state of Pará, as well to provide a consolidated partners network to prepare the groups regarding to organization, activity management and helping in the market access. The most part of the oyster famers are small producers, artisanal fishermen that found a way to manage their families via oyster farming. However, the oyster farming is a secondary activity to them, once it is still not enough to support their necessities. Nevertheless, several farmers already declared once they manage how to increase the oyster production they will be exclusively dedicated to this activity.
Acesso aberto (Open Access)
Avaliação sanitária de água de cultivo e de ostras da zona do salgado, nordeste do Estado do Pará - Brasil
(Universidade Federal do Pará, 2011-04-19) KIYATAKE, Daniela Mayumi; RIBEIRO, Karla Tereza Silva; http://lattes.cnpq.br/2654817572738748; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669
The cultivation of oyster species of the genus Crassostrea is expanding in the northeast of the Brazilian state of Pará. This study analyzes the sanitary quality of the oysters and the water in which they are cultivated in the local municipality of São Caetano de Odivelas and Curuçá. Samples were collected monthly between June, 2009, and May, 2010. Water samples were collected from the flood and the ebb tides, and approximately 15 oysters were obtained each month. Coliform concentrations were determined using the multiple-tube fermentation technique, followed by the biochemical identification of the bacteria and determination the susceptibility profile of Escherichia coli isolated from oysters and water samples. The geometric mean concentration of thermotolerant coliforms in the water was 119 MPN/100 mL in São Caetano de Odivelas and 163,21 MPN/100 mL in Curuçá, well above the limit of 43 MPN/100 mL established by the Brazilian National Environment Council (CONAMA). As Brazilian legislation on the sanitary quality of bivalve mollusks covers only the processed product, the European Union legislation, which assigns oysters for raw consumption to three sanitary classes, was adopted for the evaluation of the results of the present study. In São Caetano de Odivelas only two of the samples collected during this study were assigned to class A, seven samples to class B and three samples to class C. While in Curuçá three samples were assigned to class A, seven samples to class C and two samples to class C. The results suggest the need for mitigation measures to ensure the health quality of the oysters, such as the application of methods of depuration.
Acesso aberto (Open Access)
Estudo da biologia reprodutiva de Crassostrea gasar (Adanson, 1757) no nordeste paraense
(Universidade Federal do Pará, 2012-04-30) PAIXÃO, Leonardo Fernandes da; FERREIRA, Maria Auxiliadora Pantoja; http://lattes.cnpq.br/1832728101486131; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081
The present study analyzed gonadal development in Crassostrea gasar from an Amazonian estuary and characterized the relationship between the reproductive cycle and the variation in abiotic factors. Samples of approximately 20 oysters were collected each month between August, 2009, and December, 2010. The study period was divided into four seasonal periods (dry, dry-rainy transition, rainy, and rainy-dry transition). The salinity, pH, temperature, and dissolved oxygen concentration of the water were measured in situ during the collection of specimens. The gonads were dissected and analyzed histologically. A total of 353 specimens were collected, of which 190 were female, 161 were male, and two were hermaphrodite. Histologically, the specimens were classified in four gonadal stages: I – immature; II – maturing; III – mature, and IV – spawned (females) and spermiated (males). Of the abiotic factors analyzed, only salinity and rainfall varied significantly over the study period, with correlations being found between these factors and gonadal maturation, suggesting that they influence the reproductive cycle of the species. A predominance of mature (stage III) and maturing individuals were recorded during the rainy and rainy-dry periods (low salinity and high rainfall), whereas immature (I) and spawned/spermiated (IV) specimens were more common during the dry and dry-rainy periods (high salinity and low rainfall). Given this, the collection of seeds for farming would be recommended during the latter period, when spawned/spermiated oysters were more common.
Acesso aberto (Open Access)
Molecular identification, phylogeny and geographic distribution of Brazilian mangrove oysters (Crassostrea)
(2010) MELO, Aline Grasielle Costa de; VARELA, Eduardo Sousa; BEASLEY, Colin Robert; SCHNEIDER, Horacio; SAMPAIO, Maria Iracilda da Cunha; GAFFNEY, Patrick Michael; REECE, Kimberly S.; TAGLIARO, Claudia Helena
Oysters (Ostreidae) manifest a high degree of phenotypic plasticity, whereby morphology is of limited value for species identification and taxonomy. By using molecular data, the aim was to genetically characterize the species of Crassostrea occurring along the Brazilian coast, and phylogenetically relate these to other Crassostrea from different parts of the world. Sequencing of the partial cytochrome oxidase c subunit I gene (COI), revealed a total of three species of Crassostrea at 16 locations along the Brazilian coast. C. gasar was found from Curuçá (Pará state) to Santos (São Paulo state), and C. rhizophorae from Fortim (Ceará state) to Florianópolis (Santa Catarina state), although small individuals of the latter species were also found at Ajuruteua beach (municipality of Bragança, Pará state). An unidentified Crassostrea species was found only on Canela Island, Bragança. Crassostrea gasar and C. rhizophorae grouped with C. virginica, thereby forming a monophyletic Atlantic group, whereas Crassostrea sp. from Canela Island was shown to be more similar to Indo-Pacific oysters, and either arrived in the Atlantic Ocean before the convergence of the Isthmus of Panama or was accidentally brought to Brazil by ship.
Acesso aberto (Open Access)
Ocorrência de ostras perlíferas no Marajó, rio Pará
(2002-03) HOHN, Helmut; COSTA, Marcondes Lima da
The occurrence of perliferous freshwater oysters in the southern region of Marajó Island, at the mouth of Amazon River, is reported. The oyster's shell presents a thick layer of conchioline. A set of 12 freshwater pearls present white to dark gray colors with nacarous luster, some with golden metallic hue; sizes from 3 to 11 mm and spheric to cylindrical (with belts) to barroc forms. At long wave UV light, two samples present strong and one presents medium blue color. Paler blue colors are shown at short wave UV light. The inner side of the shell presents pale blue colors at both, long and short wave UV light. This occurrence represents, probably, the first important region in Brazil with natural pearls, opening a perspective for freshwater pearl cultivation.