Ciclo de vida e estrutura de uma assembléia de peixes teleósteos em um manguezal da Raposa, Maranhão, Brasil

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Characterization of the commercial fish production landed at Manaus, Amazonas State, Brazil

The present work aims to update a series of information about the regional fishing production, by presenting and characterizing the contribution of the different sub-systems of the Amazon basin to the catch landed at the main fishing market of Manaus, Brazil, from 1994 to 1996. Collectors specifically hired for this function registered key information on the fisheries. Thirty nine types or groups of fish were found in the fishing production landed. Jaraqui (Semaprochilodus spp.), curimatã (Prochilodus nigricans), pacu (Myleinae), matrinchã (Brycon cephalus), sardine (Triportheus spp.), aracu (Anostomidae) and tambaqui (Colossoma macropomum) were the most important items during three consecutive years. In 1994 these items summed up 91.6% of the total production; in 1995 and 1996 these values were, respectively, 85.3% and 86.4% of the total production. Tambaqui landed decreased remarkably during the period 1976-1996. There was a strong seasonal component in the production of the main species; jaraqui and matrinchã were mostly landed between April and June, while curimatã, pacu, and sardine were mostly landed during the dry season. Other important items showed a strong inter-annual variation in their production. The fishing production landed came mostly from the sub-system of the Purus River (around 30% of the total production). The subsystem of the Medium-Solimões contributed with an average of 15% and the sub-systems of the Madeira, Lower-Solimões, Upper-Amazon and Juruá, together contributed with 11.5% of the total production landed. Finally, the remaining sub-systems contributed with only 7.6% of the production.

Mutagenicity of Blue Rayon Extracts of Fish Bile as a Biomarker in a Field Study

Blue rayon (BR) in combination with the Salmonella/microsome assay was used to evaluate the mutagenicity of fish bile samples. Specimens of Mugil curema from two sites were collected over a 1-year period. Piacaguera channel contains high concentrations of total polycyclic aromatic hydrocarbons (PAHs) and other contaminants, while Bertioga channel was considered the reference sites in this study. Bile was extracted with BR and tested with TA98, TA100, and YG1041 strains with and without S9 in dose response experiments. PAH metabolite equivalents were analyzed using reverse-phase high performance liquid chromatography /fluorescence. Higher mutagenic responses were observed for the contaminated site; YG1041 with S9 was the most sensitive strain/condition. Mutagenicity ranged from 3,900 to 14,000 rev./mg at the contaminated site and from 1,200 to 2,500 rev./mg of BR at the reference site. The responses of YG1041 were much higher in comparison with the TA98 indicating the presence of polycyclic compounds from the aromatic amine class that cause frameshift mutation. TA100 showed a positive mutagenic response that was enhanced following S9 treatment at both sites suggesting the presence of polycyclic compounds that require metabolic activation. benzo(a)pyrene, naphthalene, and phenanthrene metabolite equivalents were also higher in the bile of fish collected at the contaminated site. It was not possible to correlate the PAH metabolite quantities with the mutagenic potency. Thus, a combination of the Salmonella/microsome assay with YG1041 with S9 from BR bile extract seems to be an acceptable biomarker for monitoring the exposure of fish to mutagenic polycyclic compounds. Environ. Mal. Mutagen. 51:173-179, 2010. (C) 2009 Wiley-Liss, Inc.

Monitoring pollution in river Mure , Romania, Part III: biochemical effect markers in fish and integrative reflection

Along a downstream stretch of River Mure , Romania, adult males of two feral fish species, European chub (Leuciscus cephalus) and sneep (Chondrostoma nasus) were sampled at four sites with different levels of contamination. Fish were analysed for the biochemical markers hsp70 (in liver and gills) and hepatic EROD activity, as well as several biometrical parameters (age, length, wet weight, condition factor). None of the biochemical markers correlated with any biometrical parameter, thus biomarker reactions were related to site-specific criteria. While the hepatic hsp70 level did not differ among the sites, significant elevation of the hsp70 level in the gills revealed proteotoxic damage in chub at the most upstream site, where we recorded the highest heavy metal contamination of the investigated stretch, and in both chub and sneep at the site right downstream of the city of Arad. In both species, significantly elevated hepatic EROD activity downstream of Arad indicated that fish from these sites are also exposed to organic chemicals. The results were indicative of impaired fish health at least at three of the four investigated sites. The approach to relate biomarker responses to analytical data on pollution was shown to fit well the recent EU demands on further enhanced efforts in the monitoring of Romanian water quality.

Abundance and biomass of near-surface ichthioplankton in the Western Pacific

During Cruise 50 of R/V Vityaz ichthyoplankton in surface waters was collected by a neuston otter trawl for many days in four study areas of the Western Tropical Pacific. Obtained results describe quantitative distribution of ichthyoplankton and small fishes in surface waters. The near-surface layer of the ocean (about 30-40 cm thick) can be considered as a special biotope, its population forms an independent biocoenosis - hyponeuston. Species composition of this community (particularly, composition of fish components) in the tropical zone has been studied to some degree, but structure of the biocoenosis as well as biomass and quantitative relationships of species have not been investigated at all. In this paper the authors discuss the method of collecting surface samples that is quite suitable for quantitative calculations and also present the first results obtained using this method, which described quantitative distribution of ichthyoplankton and small fishes in surface waters.

Biodiversidade e abundância da ictiofauna associada ao cultivo orgânico de Litopenaeus vannamei (Boone, 1931)

The expansion of shrimp farming has caused a series of environmental impacts, often as a result of lack of planning and adequate management. Organic aquaculture has emerged as an alternative to conventional shrimp farming, and differently, aims at the economical, ecological and farming potential of other organisms, such as fishes, oysters and seaweeds. The present study aimed at evaluating the biological diversity and abundance of the ichthyofauna associated to Litopenaeus vannamei organic culture at PRIMAR farm (Rio Grande do Norte, Brazil). The sampling period consisted of four culture cycles (1, 2, 3, and 4) accomplished in four grow-out ponds (V1, V7, V2, and V4) in 2005. The first two culture cycles were carried out during the rainy season, and the last two cycles, during the dry season. Environmental (temperature, salinity, transparency, and rainfall), biodiversity (diversity and uniformity and abundance indexes) of the ichthyofauna, and shrimp productivity data were collected throughout these four culture cycles. The results obtained for the environmental variables showed that both salinity and transparency oscillated in a significant way (p < 0.001) between culture cycles. In relation to the abundance of the ichthyofauna, fifty four species associated to the organic culture of Litopenaeus vannamei were collected and identified at PRIMAR. For the biodiversity criterion, larger species richness (S = 46) and uniformity (E = 0.59 ± 0.16) were observed during cycles 3 and 4 than in cycles 1 and 2 (S = 41 and E = 0.15 ± 0.12). A positive and significant correlation was obtained for the transparency with diversity and uniformity of fish species between cycles 1 and 2 (wet season) and cycles 3 and 4 (dry season) (p < 0.017 - Shannon Index; p < 0.008 - Pielou Index, respectively). A correlation could not be established between shrimp productivity and fish biomass. However, fish biomass decreased from cycles 1 and 2 to cycles 3 and 4, concomitant with an increase in shrimp productivity, most probably due to a higher (from 58.0% to 71.0%) shrimp survival. Regarding the culture potential of the ichthyofauna, three species (Mugil curema, Mugil liza and Chaetodipterus faber) were identified as potential farming alternatives, either singly or in consortium with Litopenaeus vannamei. A fourth species (Centropomus undecimalis) was indicated as an alternative for single culture or in consortium with other fish species. In conclusion, the large diversity of estuarine fishes associated to Litopenaeus vannamei farming observed at PRIMAR clearly indicated the ecological feasibility for organic aquaculture in northeastern Brazil

Effects of hot and cold smoking processes on organoleptic properties, yield and composition of matrinxa fillet

Foi avaliado o efeito do processo de defumação a quente (45-90ºC/5 horas) e a frio (27-45ºC/10 horas) nas propriedades organolépticas, no rendimento e na composição dos filés de matrinxã (Brycon cephalus). Não houve diferença significativa no rendimento de filés defumados e não-defumados. As perdas no processo de defumação foram significativamente maiores para defumação a quente (19,37%) em comparação à defumação a frio (17,08%). O processo de defumação reduziu a umidade (in natura = 72,91%; defumado a quente = 58,51%; e defumado a frio = 59,68%) e aumentou os teores de proteína bruta, lipídios e cinzas. Houve diferença significativa somente nos teores de proteína no defumado a quente (28,07%) e defumado a frio (27,14%). O processo a frio resultou em melhor aparência e cor de filé, enquanto o processo a quente melhorou o sabor, o teor de sal e a aparência geral. O aroma e a textura não diferiram significativamente entre os processos. O processo de defumação a quente melhora as propriedades organolépticas e os níveis de proteína do filé de matrinxã.

Biodiversidade e abundância da ictiofauna associada ao cultivo orgânico de Litopenaeus vannamei (Boone, 1931)

The expansion of shrimp farming has caused a series of environmental impacts, often as a result of lack of planning and adequate management. Organic aquaculture has emerged as an alternative to conventional shrimp farming, and differently, aims at the economical, ecological and farming potential of other organisms, such as fishes, oysters and seaweeds. The present study aimed at evaluating the biological diversity and abundance of the ichthyofauna associated to Litopenaeus vannamei organic culture at PRIMAR farm (Rio Grande do Norte, Brazil). The sampling period consisted of four culture cycles (1, 2, 3, and 4) accomplished in four grow-out ponds (V1, V7, V2, and V4) in 2005. The first two culture cycles were carried out during the rainy season, and the last two cycles, during the dry season. Environmental (temperature, salinity, transparency, and rainfall), biodiversity (diversity and uniformity and abundance indexes) of the ichthyofauna, and shrimp productivity data were collected throughout these four culture cycles. The results obtained for the environmental variables showed that both salinity and transparency oscillated in a significant way (p < 0.001) between culture cycles. In relation to the abundance of the ichthyofauna, fifty four species associated to the organic culture of Litopenaeus vannamei were collected and identified at PRIMAR. For the biodiversity criterion, larger species richness (S = 46) and uniformity (E = 0.59 ± 0.16) were observed during cycles 3 and 4 than in cycles 1 and 2 (S = 41 and E = 0.15 ± 0.12). A positive and significant correlation was obtained for the transparency with diversity and uniformity of fish species between cycles 1 and 2 (wet season) and cycles 3 and 4 (dry season) (p < 0.017 - Shannon Index; p < 0.008 - Pielou Index, respectively). A correlation could not be established between shrimp productivity and fish biomass. However, fish biomass decreased from cycles 1 and 2 to cycles 3 and 4, concomitant with an increase in shrimp productivity, most probably due to a higher (from 58.0% to 71.0%) shrimp survival. Regarding the culture potential of the ichthyofauna, three species (Mugil curema, Mugil liza and Chaetodipterus faber) were identified as potential farming alternatives, either singly or in consortium with Litopenaeus vannamei. A fourth species (Centropomus undecimalis) was indicated as an alternative for single culture or in consortium with other fish species. In conclusion, the large diversity of estuarine fishes associated to Litopenaeus vannamei farming observed at PRIMAR clearly indicated the ecological feasibility for organic aquaculture in northeastern Brazil