Navegando por CNPq "CNPQ::CIENCIAS AGRARIAS::RECURSOS PESQUEIROS E ENGENHARIA DE PESCA::AQUICULTURA"

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Acesso aberto (Open Access)
Biodiversidade e variação espaço-temporal da abundância das populações de camarões e estrutura populacional de Farfantepenaeus subtilis (Pérez-Farfante, 1967) (Penaeidae) em um estuário do litoral amazônico brasileiro
(Universidade Federal do Pará, 2013-04-22) FERREIRA, Valdimere; MARTINELLI-LEMOS, Jussara Moretto; http://lattes.cnpq.br/5264841936875017
This study investigated the biodiversity and spatial-temporal distribution of abundance of populations of shrimp and described the population structure of the Farfantepenaeus subtilis in an Amazonian Estuary. The shrimps were collected monthly from August 2006 to July 2007 in the rainy (January to June) and dry (July to December) season with bottom trawling and beach seine in the Middle-Upper (MU), Medium (M) and Low (L) sectors. In each sector two sites were sampled, of which two bottom trawling five minutes each and three beach seine of 150 m2 each were performed. The variables: temperature, pH and salinity of water and grain size and organic matter of the sediment were analyzed. For each shrimp were recorded the length Total - CT and cephalothorax - CC, total weight, sex and stage of gonadal maturation. The salinity differ between sectors I and MS (p <0.05) and M showed low organic matter content. The salinity differ significantly among sectors I and MS (p <0.05) and M showed low organic matter content. In all sectors the sand grains were prevalent on substrate, especially the fine sand in sector M. A total of 11,939 shrimps were collected, divided into twelve species and six families. Palaemonidae and Penaeidae had higher richness with five and three species, respectively. Penaeidae, Sergestidae and Palaemonidae had higher abundance, with Xiphopenaeus kroyeri, F. subtilis, Acetes marinus and Nematopalaemon schmitti, contributing 43, 31, 21 and 1.3% of the total catch, respectively. The species F. subtilis, X. kroyeri and Litopenaeus schmitti contributed 97% of the total biomass. The density and biomass from F. subtilis differ between the rainy and dry seasons (p <0.05) being higher in rainy season. In the rainy season, the density of X. kroyeri was higher in sectors M and I and dry season in sectors MS and M with higher biomass in sector I in both seasons. The density and biomass A. marinus was high in sector I (p <0.05). The salinity, sand, silt and clay significantly influenced the spatial and temporal distribution of abundance of shrimps (p <0.05). The CC of female F. subtilis was higher than males with 13.7 mm and 12.8 mm, respectively and differed in March (p <0.05). Females were more abundant and sex ratio was 0.8:1 especially in January, February, May and the total analysis (p <0.05). Developed shrimps occurred in rainy and abundance of juveniles was higher from January to June when it occurs the most intense peak spawning in the open sea.
Acesso aberto (Open Access)
Caracterização do sistema produtivo da aquicultura da microrregião de Cametá – Pará
(Universidade Federal do Pará, 2013) FERREIRA, Palmira Francisca Gonçalves; FUJIMOTO, Rodrigo Yudi; http://lattes.cnpq.br/9538142371454660
This research is aimed to present a diagnosis of aquaculture activity in the micro region of Cametá - Pará, emphasizing the factors that influence the development of activity and the level of competitiveness through the Competitive Performance Index (CPI) in order to provide indicators that can facilitate decision making in the areas of promoting aquaculture establishment as an economic activity. Data collection was performed by using questionnaires that sought to investigate the aspects relevant to productive activity. The data was processed and analyzed using the statistical SPSS software, version 13. This software made it possible to obtain a reduced linear structure of the original data set, through the summarization of the information contained in the variables creating smaller variable sets lalled factors, to identify the Competitive Performance Index (CPI) with respect to the variables studied. The results showed that 70.50% of the region's farmers have a primary education and only 1.44% attended or initiated higher education. 91,37% of the employees are members of the farm owners family. The average area intended for cultivation was 500 m2. The largest was found in Oeiras do Pará, which is also the largest municipality in area. The means of production include the creation of ponds in lowland areas (78.05%), in net-cage 13,3% and conventional production system with 8,65%. The prevalent mode of cultivation is the monoculture, especially the round fish tambaqui and tambacu (54%). Factor analysis extracted four factors representative of the development in the region: the productive system dimension, which explained about 27% of the total variance; commercial dimension, accounting for 15.15%; efficiencydimension explained 13.3% of the total and work dimension that explained 12.5% of the total variance. These factors influence the development of activity and should direct the actions of rural entrepreneurs and policy with the aim of improving fish farms so that they can boost production and meet growing demands for food quality.
Acesso aberto (Open Access)
Caracterização estrutural e ultraestrutural das células do epitélio gonadal de Hypophthalmus Marginatus (Valenciennes 1840) durante a espermatogênese
(Universidade Federal do Pará, 2014-09-05) GONÇALVES, Liziane Amaral Barbosa; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081
Hypophthalmus marginatus is a siluriforme, belonging to the family Pimelodidae. This species is highly consumed in eastern Amazonia and has a wide socio-economic importance to the region. Studies on the histological characterization of the reproductive system are still unknown in this species. Therefore, this study serves as a tool for biotechnology techniques, necessary for the production in captivity, since this species is one of the fishing resource most intensively exploited by artisanal fisheries. The aim of this study was to characterize the structural and ultrastructural features of germinal epithelium cells of Hypophthalmus marginatus during spermatogenesis. 168 specimens were collected from December 2011 to December 2012. Macroscopically were identified 69 adult males. In field, ventral incision was held in fishes and fragments of testicles from the median region and semen were removed. Then the material was subjected to processing and analysis of light microscopy, transmission electron microscopy and scanning. The data revealed that the germ cells proliferate inside the spermatic cyst synchronously. Spermatids enter at the spermiogenesis process through three distinct stages of cell differentiation. The nucleus does not move relative to the axis flagellar and the centrioles don't migrate to the nucleus. The spermatozoids showed a spherical head with the highly condensed nucleus and no acrosome. The intermediary piece was short containing a single long flagellum. The axoneme presents the structure of microtubules within the pattern (9 + 2). The nuclear fossa housed the proximal centriole partially. The presence of spermatogenic cells in the same subphase of meiosis inside the cyst is characterized as cystic spermatogenesis, with synchronous growth of the cells. This suggests that spermiogenesis of H. marginatus is of type III and the presence of nuclear fossa is considered a distinctive feature for the species, which differs from other pimelodids.
Acesso aberto (Open Access)
Composição, abundância e pesca da ictiofauna como indicadores do estado de conservação de dois lagos de várzea no baixo Rio Amazonas (Brasil)
(Universidade Federal do Pará, 2010) ALMEIDA, Morgana Carvalho de; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
The Amazon floodplain has a rich biodiversity and its characteristics influence the economically and ecologically important natural aquatic resources for the people. On the basis of these information, the objective of this research was to characterize the composition and abundance of ichthyofauna in two floodplain lakes in the Santarem region, and to understand the use I buy fishers in the Piracãoera and Campos fishing communities, in the Urucurituba region, and Barreira and Correio communities in the Tapará region. Samples were taken in the Aramanaí and Curiquara lakes considering the four hydrological periods (rising, flood, low, dry) for the period between July of 2006 and April of 2007. For the fish sampling were used set gillnets batteries. To collect data on catches of fishermen, forms were used that contained information about the characteristics of the fisheries. We caught 10,146 fish, which were distributed in 156 species, 27 families and 8 orders. The most abundant families in number of individuals were Sciaenidae and Loricariidae. In Aramanaí Lake, the Loricaria sp, was the species with the highest CPUAn with 0.02 individuals per m². hour. In terms of CPUAp featured species Potamotrygon motoro, with 0.13 g.m ². hour and Pterygoplichthys pardalis with 0.11 g. m². hour. In Curiquara Lake, the main catch in number of individuals was represented by the Pachypops fourcroi with 0,001 individuals per m² of gillnet. Curiquara and Aramanaí lakes 9 trophic guilds were identified and for both lakes fish piscivores and detritivores showed the largest catch by weight. The average length of individuals caught in the lakes was 20.27 ± 7.53 cm. The highest mean length of individuals was in the flood and lower in the low period. When fishing is practiced by fishermen used a variety of fishing gear devices highlighting the gill netting. The use of gear depends on the environment exploited, target species, and in addition to the season, and there may be combinations of more than one gear during the catch. The average yield of the fisheries in the two regions was 10 kg.fishermen.dia-1. In Urucurituba region the CPUE average was 16kg.fishermen.dia-1, in Tapará was 4.5 kg.fishermen.dia-1. The Urucurituba’s fishermen showed the higher catch volume and fish marketing. These communities are partially fulfilling the rules of the fisheries agreements.
Acesso aberto (Open Access)
Crescimento e produção de pirarucu, Arapaima gigas, sob diferentes densidades de estocagem em associação com búfalas leiteiras
(Universidade Federal do Pará, 2001-10) IMBIRIBA, Emir Palmeira; LOURENÇO JÚNIOR, José de Brito; http://lattes.cnpq.br/2919433679918544
With the objective of evaluating four stock densities of pirarucu (Arapaima gigas) and to identify the one that provides the best productive performance, in length and weight gain to make possible its intensive culture, a research was carried out, during 360 days. using the densities of 5, 10, 15 and 20 fishes per 100 m2 of inundate area. Live tilapias (Tilapia nilotica), captured in a dam used for milk buffaloes management, equivalent to 6% of the pirarucu live weight, were used during four days per week. The design was completely randomized with four treatments and two replications. The data were analyzed on the basis of the application of the exponential model of growth. Mathematical expressions were obtained for each stockage density. Simple linear regression analysis were made. - However, until the first 120 days, no significant difference in weight could be observed among the four study densities. The values of the angular coefficient of the relation weight/length of pirarucu showed that its growth is of the allometric type. The maximum total size was 107.66 cm and the maximum weight was 13.43 kg, in the density of five fishes per 100 m2. However, the highest biomass, of 85.69 kg per 100 m2, was observed in the density of 10 fishes per 100 m2, suggesting that this density would be the most adequate for using in intensive systems. The excellent ponderal development of pirarucu, indicates the potential use of this species, in intensive systems associated with buffaloes.