Navegando por Assunto "Peixe de água doce"

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Acesso aberto (Open Access)
Description of a new species of Ituglanis (Siluriformes: Trichomycteridae) from Serra dos Carajás, rio Tocantins basin
(2012-09) WOSIACKI, Wolmar Benjamin; DUTRA, Guilherme Moreira; MENDONÇA, Marina Barreira
A new species of Ituglanis is described from the rio Tocantins basin, State of Pará, Brazil. Ituglanis ina, new species, is distinguished from its congeners by the presence of a dark vertical bar over the base of the caudal-fin rays (vs. no bars over caudal-fin base); and by the presence of a middle trunk line of tiny neuromasts extending along the flank until the vertical through the dorsal fin, or near the caudal-fin base (vs. no middle trunk line of tiny neuromasts). Ituglanis ina can be further distinguished by a combination of characters related to color pattern and morphology. Comments on the relationship between Ituglanis species are presented.
Acesso aberto (Open Access)
Ecomorfologia trófica de Acarichthys heckelii (Müller & Troschel, 1849), Heros efasciatus Heckel, 1840 e Mesonauta insignis (Heckel, 1840) (Perciformes:Cichlidae) nas reservas de desenvolvimento sustentável de Amanã e Mamirauá, Amazônia
(Universidade Federal do Pará, 2011-08-18) LINS, Paulo Marcelo de Oliveira; CAMARGO-ZORRO, Mauricio; http://lattes.cnpq.br/5423657235023988
The cichlids are one of the most diverse families of living freshwater fishes, about 1.900 species. A. heckelii, H. efasciatus and M. insignis are exploited at the Sustainable Development Reserves of Amanã and Mamirauá according to sustainable management plan. A free-size canonical variable analysis was made to investigate the ecomorphological patterns of variation among the three species from Amanã and Mamirauá Reserves. The three species formed different groups like species, ontogeny phase and habitat. Those groups were divided as result of characters like mouth width and head length. Differences among juveniles and adults were significant in relative area of eye and aspect-ratio of caudal fin. The diet composition indicated that three studied species have a converged feeding habit on insects in both black and white waters habitats.
Acesso aberto (Open Access)
Efeito da exploração madeireira na estrutura ecomorfológica das assembleias de peixes em riachos de terra firme na Amazônia Oriental
(Universidade Federal do Pará, 2018-04) JACOB, Laís Lobato; PRUDENTE, Bruno da Silveira; http://lattes.cnpq.br/0790796091423878; https://orcid.org/0000-0003-4226-2431; SILVA, Rogério Rosa da; http://lattes.cnpq.br/5989181105383977
Changes resulting from logging modify the physical structure of stream habitats indirectly, and consequently the ecomorphological structure of fish assemblages. The present study aimed to evaluate the effect of changes in the physical structure of the habitat resulting from conventional logging (CL) and reduced-impact logging (RIL), in the ecomorphological structure of the fish assemblages of streams of the Eastern Amazon, verifying (1) which variables of the physical structure of the habitat are associated to the different methods of exploration; (2) if there is a difference in the ecomorphological structure of the fish assemblages of the different treatments, and (3) which ecomorphological characters are associated with physical variables of the habitat. In each stream 14 physical variables of the habitat were measured, as well as fish samples collected using hand nets. The collected specimens were affected in Eugenol, fixed in 10% formalin and after 48h transferred to 70% alcohol. Possible differences in habitat structure and ecomorphological structure of fish assemblages between treatments were evaluated by Multiple Linear Discriminant Analysis (MLDA). The relationships between the habitat variables and the ecomorphological characters were evaluated through Redundancy Analysis (RDA). The structure of the streams habitat differed among all treatments, with control areas showing higher vegetation cover and higher average substrate size. As for ecomorphology, we also found that there was a difference in ecomorphological structure among all treatments. In EC environments, species with greater relative head length, with the wider pectoral fin and with more compressed caudal peduncle were predominant in these environments; in control areas, species with wider mouth were favored; and in RIL areas, more flattened species were predominant. Logging affects the habitat structure of the streams, resulting in loss of plant cover and average substrate size. There was a reduction of plant cover and average substrate size in areas of EC and RIL areas. In this sense, it is believed that both the EC and the RIL have the potential to alter the ecomorphological structure, and consequently the ecosystem services provided by the assemblages of fish from streams in the Amazon. So even if EIR reduces damage to forests, it is failing to protect the ecosystems of streams, since changes have been observed in these environments when compared to control areas. However greater efforts should be employed to fully understand such a relationship and proportions that the damage can cause to the ecosystem.
Acesso aberto (Open Access)
Estudo sobre o crescimento do tambaqui (Colossoma macropomom) submetido à dieta suplementada com camu camu (Myrciaria dubia) em água corrente e aquecida
(Universidade Federal do Pará, 2018-09) CANTO, Miguel Angelo de Oliveira; SALGADO, Claudio Guedes; http://lattes.cnpq.br/9601463988942971; DINIZ, Domingos Luiz Wanderley Picanço; http://lattes.cnpq.br/9601463988942971
This study investigated the growth of the tambaqui (Colossoma macropomum) (Cm), an caracid teleost in the Amazon region, in the laboratory. Juvenile fish were submitted to the simulation of the natural conditions of feeding, climate and running water, corresponding to the flood and dry periods of the Amazonian hydrological cycle. In the flood, its diet is predominant of fruits and seeds, the environment is mild (28 ± 2°C) and the current is higher (0.2 to 0.3 m/s). In drought, the feed is based on animal protein, there is no current and the average temperature rises (34 ± 2°C). Therefore, the aim of this study was to investigate the effects of Myrciaria dubia (Md) on the growth of Cm in the drought or flood simulations with respect to the mild (28 ° C) or heated (34 ° C), standing or running water (0,2 or 0.3m/s), and diet with higher (45%) or lower (32%) crude protein (CP) content. For this, juveniles of Cm were acclimatized (70 or 126 days) in tanks of (310 or 500 liters) according to the experimental protocol. Protocol I: diet with fractioned daily supply (3x/day) and supplemented with Md; crude protein (45 or 32%); running water (0.2 m/s) or stopped at 28 or 34°C; analysis of muscle contents of IGF1 and total lipids. protocol II: single or fractioned offer (3x / day); standing or running water (0.3 m/s), intercalated, (12 hours) or continuous; quantification of the cavity fat mass. The results are presented on average plus or minus the standard error of the mean and compared by ANOVA plus Bonferrone post-test. Correlation test for weight, length or cavity fat versus running water; in the conditions of single or fractional supply was performed to verify interrelations between the phenomena studied. A potentiation of body mass expansion rather than length occurred by the diet supplemented with Md in standing and heated water. In contrast similar potentiation occurred for running and heated water in the 45% CP diet. In turn, lower growth performance (weight and length) was observed in the group submitted to a 32% CP diet. The running water also potentiated the accumulation of cavitary and muscular fat of total lipids, suggesting that the swimming effort demands accumulation of potential energy possibly related to the preservation of protein anabolism, since the protein content in the muscle tissue was not altered. On the other hand, the single daily supply of food was not enough to maintain the resulting growth performance to sustained swimming (running water). In the fractioned supply, the group submitted to continuous running water showed the best performance, suggesting that sustained swimming in running water may be a determinant factor for the growth of Cm if it is offered a diet with high protein content, considering the warm environment as the most favorable. Finally, the increased IGF-1 content in the muscle confirms the participation of this growth factor as the final pathway of humoral regulation of muscle hypertrophy. Hypertrophy results in increased swimming effort, and, surprisingly, in response to diet supplemented by Md.
Acesso aberto (Open Access)
Expressão gênica durante o desenvolvimento ocular e regulação de assimetria de opsinas na espécie Anableps anableps, peixe de quatro olhos
(Universidade Federal do Pará, 2022-11) SOUSA, Daniele Salgado de; SCHNEIDER, Patrícia Neiva Coelho; http://lattes.cnpq.br/9584217233879031
The ocular development is a complex process orchestrated by several events that include: cell specification, morphogenesis and differentiation. All these developmental and functional processes are extremely conserved among living vertebrate species, however, unique adaptations are sometimes observed, such as in fish of the genus Anableps. Unlike most fishes, which use their eyes to explore a submerged world, in Anableps anableps (Anablepidae: Cyprinodontiformes), the eye is adapted for the simultaneous perception of a world above and below the water line. These exceptional adaptations include: duplicated corneas and pupils, as well as a specialized retina region associated with simultaneous aerial and aquatic vision, and which have asymmetrical gene expression. Recently, by transcriptomic analysis of the developing eyes of A. anableps, 20 non-visual opsin genes were identified to be asymmetrically expressed between pre- and post-duplication stages of corneas and pupils. Thus, here, we analyzed by in situ hybridization the gene expression of a bistable opsin (parapinopsin) and a neuropsin (Opn5) in A. anableps larvae. Our data showed that the pattern of gene expression of these opsins is symmetrical between the dorsal and ventral retina, respectively, with expression in the ONL, INL and GCL layers. We also investigated the expression of three non-visual melanopsin genes (opn4x1, opn4x2, opn4m3), one eleost multiple tissue opsin (tmt1b), and two visual opsins (lws and rh2-1) in the dorsal and ventral retinas of juvenile A. anableps, after changing the photic conditions in which the juvenile fish were. Then, we showed that in the transition from an environment of high turbidity to one of clear water, opsins have their expression patterns changed. Additionally, by immunofluorescence, we revealed the expression of Lamin A/C, proteins expressed as part of eye development in A. anableps as well as in other developing organisms, as well as in adult individuals. Therefore, we believe that the information described here elucidates many aspects of the molecular mechanisms behind the development and adaptive plasticity of A. anableps’ eyes.
Acesso aberto (Open Access)
Morphological and hematological studies of Trypanosoma spp. infecting ornamental armored catfish from Guamá River-PA, Brazil
(2013-09) FUJIMOTO, Rodrigo Yudi; NEVES, Mikaelle de Souza; SANTOS, Rudã Fernandes Brandão; SOUSA, Natalino da Costa; COUTO, Márcia Valéria Silva do; LOPES, Josiane N. S.; EIRAS, Jorge Costa
A total of 281 specimens of freshwater armored ornamental fish species (Leporacanthicus galaxias, Lasiancistrus saetiger, Cochliodon sp., Hypostomus sp., Pseudacanthicus spinosus, Ancistrus sp. and Rineloricaria cf. lanceolata) were captured at the hydrological basin of Guamá River, Pará, Brazil. The infection by Trypanosoma spp. was inspected. The morphological and morphometric characterization of the parasites and the hematological parameters were determined. Leporacanthicus galaxias and Pseudacanthicus spinosus presented 100% infection prevalence, and the other species showed a variable prevalence of infection. The parasites showed clearly different morphotypes and dimensions, and probably belong to different species. The hematological response to the infection varied with the host. Cochliodon sp. showed no differences between infected and not infected fish. In other species several modifications on some hematological parameters were found, but apparently without causing disease. It is emphasized the possibility of introduction of the parasites in new environments due to the artificial movements of these ornamental fish.
Acesso aberto (Open Access)
Revisão taxonômica de Electrophorus Gill, 1864 (Gymnotiformes, Gymnotidae) com descrição de quatro espécies novas
(Universidade Federal do Pará, 2010) CASTRO, Natália de Castro e; WOSIACKI, Wolmar Benjamin; http://lattes.cnpq.br/0040413891328104
Acesso aberto (Open Access)
Revisão taxonômica do gênero Microcharacidium Buckup, 1993 (Ostariophysi: Characiformes: Crenuchidae)
(Universidade Federal do Pará, 2019-02) VIEIRA, Lorena Sanches; FERREIRA, André Luiz Netto; http://lattes.cnpq.br/1272360228203358; https://orcid.org/0000-0002-3096-0411