Dissertações em Ecologia Aquática e Pesca (Mestrado) - PPGEAP/NEAP
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3479
O Mestrado Acadêmico iniciou em 2007 e pertence ao Programa de Pós-Graduação em Ecologia Aquática e Pesca (PPGEAP) do Núcleo de Ecologia Aquática e Pesca da Amazônia (NEAP) da Universidade Federal do Pará (UFPA).
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Navegando Dissertações em Ecologia Aquática e Pesca (Mestrado) - PPGEAP/NEAP por Autor "FERREIRA, Maria Auxiliadora Pantoja"
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Item 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/4371300451793081The 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.Item Acesso aberto (Open Access) Utilização de peixes nativos da Amazônia como biomarcadores na avaliação da qualidade da água de uma área industrial no rio Pará - PA - Brasil(Universidade Federal do Pará, 2011) MONTES, Caroline da Silva; FERREIRA, Maria Auxiliadora Pantoja; http://lattes.cnpq.br/1832728101486131; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081Indiscriminate dumping of toxic substances impairs and deteriorates the water quality. Fish gills have a large surface area; they remain in close contact with the external environment and are particularly sensitive to changes in water quality, for this reason they are quite relevant for environmental monitoring. This study analyzes the gill structure of the fish species Plagioscion squamossissimus and Lithodoras dorsalis from two different sites located an Amazon estuary. A total of 324 specimens were used, this total 176 were P. squamossissimus and 148 L. dorsalis, removing the second gill arch for histological, ultrastructural and immunohistochemical analyses. The histological changes were analysed semiquantitatively according to the histopathological evaluation. The sampled sites differ regarding the rate of occurrence of altered animals, only site A showed healthy animals, 84% of L. dorsalis and 77% of P. squamossissimus had normal gill structure, with the lamellae lined by simple squamous epithelial, composed of pillar, mucous and chloride cells. However, all the specimens collected in sites B revealed tissue changes in the gill lamellae such as: aneurysm; epithelial lifting; cell proliferation; lamellar fusion and cell hypertrophy, this result was also confirmed by scanning electron microscopy. TUNEL analysis indicated that only animals captured on site B showed apoptotic cells. The presence of injury in gill tissues in the animals captured on site B emphasizes the need for more effective pollution control measures with regards to discarding pollutant loads as well as the need for urban planning in this region.