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The ontogeny of the digestive capacities in fish is species-specific and its knowledge is essential for understanding the nutritional requirements of fish larvae. While the Amazon basin contains the world's highest fish biodiversity, the molecular basis of the early digestive physiology has not yet been reported in any Amazonian fish species. In order to increase basic knowledge on the molecular ontogeny of the digestive system of a commercially important Amazonian fish species, six digestive enzyme genes (α-amylase, phospholipase A2, lipoprotein lipase, trypsin, chymotrypsin, and pepsin) were isolated and identified, and their expression analyzed from 3 to 24 days post fertilization (dpf) in Pseudoplatystoma punctifer, a catfish species with high potential for aquaculture diversification. The present results, together with those previously obtained on the development of the digestive enzyme activity, showed that gene expression and enzymatic activities are synchronized and that the enzymatic machinery of P. punctifer was completely prepared for the onset of exogenous feeding (4 dpf, 6 mm total length, TL) and had reached its maturity between 10 and 13 dpf (11–14 mm TL). This indicated that the transition from the larval to the juvenile mode of digestion had been completed and they were suitable for weaning under culture conditions. Furthermore, the gene expression analyses suggest that this species displays an omnivorous behavior with a preference towards carnivory during early development. The present study provides the first comprehensive ontogenetic analysis of the digestive function from a molecular point of view of a species of the genus Pseudoplatystoma, and contributes to the development of feeding strategies in the context of South American aquaculture diversification. info:eu-repo/semantics/acceptedVersion

The Neotropical catfish genus Pseudoplatystoma comprises eight species of large size, widely distributed in South American basins. The endangered species P. magdaleniatum is endemic to Magdalena basin (Colombia), experiences high fishing pressure and its population genetics is relatively unknown. To study the genetic status and structure of P. magdaleniatum, 25 species-specific polymorphic microsatellite loci were developed using next-generation sequencing and then tested in samples collected in the Magdalena-Cauca basin. Based on 15 of these loci, P. magdaleniatum showed a high number of alleles per locus (9-10), high values of observed (0.762-0.798) and expected (0.770-0.791) heterozygosities, recent reduction of population size and gene flow. These findings constitute a baseline to measure potential changes in genetic diversity and structure of this commercially important species in a basin undergoing high anthropogenic activities. RESUMEN El género de bagres neotropicales Pseudoplatystoma comprende ocho especies de gran tamaño, ampliamente distribuidas en las cuencas de Suramérica. La especie en peligro de extinción P. magdaleniatum es endémica de la Cuenca del Magdalena (Colombia), experimenta una alta presión pesquera y su genética poblacional es relativamente desconocida. Para estudiar el estado y estructura genética de P. magdaleniatum, se desarrollaron 25 loci microsatélites polimórficos especie específicos utilizando secuenciación de próxima generación y se evaluaron en muestras recolectadas en la Cuenca del Magdalena-Cauca. Con base en 15 loci, P. magdaleniatum mostró un alto número de alelos por locus (9-10), valores altos de heterocigosidad observada (0.762-0.798) y esperada (0.770-0.791), reducción reciente del tamaño poblacional y flujo génico. Estos hallazgos constituyen una línea de base para medir cambios potenciales en la diversidad y estructura genética de esta especie comercialmente importante en una cuenca sometida a altas actividades antropogénicas.

Fish skin colouration has been widely studied because it involves a variety of processes that are important to the broad field of the developmental biology. Mathematical modelling of fish skin patterning first predicted the existence of morphogens and helped to elucidate the mechanisms of pattern formation. The catfishes of the genus Pseudoplatystoma offer a good biological study model, since its species exhibit the most spectacular and amazing variations of colour patterns on the skin. They present labyrinths, closed loops (or cells), alternate spots and stripes, only spots and combinations of these. We have extended a well known mathematical model to study the skin of Pseudoplatystoma. The basic model is a two component, non-linear reaction diffusion system that presents a richness of bifurcations. The extended model assumes that there are two interacting cell/tissue layers in which morphogens diffuse and interact giving rise to the skin colouration pattern. We have found that by varying only two parameters we are able to accurately reproduce the distinct patterns found in all species of Pseudoplatystoma. The histological analysis of skin samples of two species of this genus, with different patterns, revealed differences on the disposition of the colouration cells that are consistent with our theoretical predictions. Fil: Scarabotti, Pablo Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentina Fil: Govezensky, Tzipe. Universidad Nacional Autónoma de México; México Fil: Bolcatto, Pablo Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; Argentina Fil: Barrio, Rafael Ángel. Universidad Nacional Autónoma de México; México

The present study proposes to characterize the parasites isolated during the initial phase of production in fish farms located in Mato Grosso do Sul in the central-western region of Brazil, using histopathology analysis and molecular techniques. A total of 340 hybrid surubim fish (Pseudoplatystoma reticulatum × P. corruscans) from four farms were examined during the co-feeding phase. Histopathology analysis showed that 10.9% (n = 37) of the fish were infected with parasites. Branchitis, lifting epithelium, hypertrophy of epithelial cells, lamellar fusion, aneurisms and infection in the bone tissue of the gill filament was observed. The parasite species was determined by amplification of the 18S rRNA gene followed by sequencing. The phylogenetic analysis of nucleotide sequences indicates a close relationship (99.6%) with Henneguya pseudoplatystoma reported to be infecting the hybrid Pseudoplatystoma. This study demonstrates the occurrence of H. pseudoplatystoma in hybrid surubim (P. reticulatum × P. corruscans) during the co-feeding phase in fish farms in Mato Grosso do Sul. Also, molecular techniques provide a faster and sensitive method to identify fish parasites, and may assist in the development of new management techniques aimed at improving the sanitary conditions contributing to the reduction of mortality rates in these animals.

Made available in DSpace on 2020-12-12T02:04:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 This study evaluated the supplementation of vitamin C in diets for Pseudoplatystoma coruscans (surubim) juveniles. The effects of high concentrations of vitamin C were evaluated through the histological skin alterations regarding the structure of epidermis and collagen deposition. Ascorbic polyphosphate (AP) was used as a source of vitamin C in the diet of the surubim juveniles at concentrations of 500, 1000, 1500, 2000 and 2500 mg of AP/kg diet added to a basic diet (control; 0 mg AP/kg diet). After 90 days, six animals per treatment were euthanized and fragments of skin were sampled. The histological cuts were stained with hematoxilin - eosin (HE), Masson tricromic (TM), and Periodic acid Schiff (PAS). The epidermis showed disarrangement of the club cells in fish from control group and in fish fed with the 2000 and 2500 mg of AP/kg of diet. The treatment with 2500 mg of AP/kg of diet also caused the lowest epidermis height. However, no morphological skin alterations were observed on treatments 500, 1000, and 1500 mg of AP/kg of diet. Thus, decreases in epidermis height and changes in club cells arrangement can be recognized as new clinical signs of hypervitaminosis C in that fish, hindering skin development. EMBRAPA-Tabuleiros Costeiros Laboratório de Enzimologia Departamento de Bioquímica Universidade Federal de Pernambuco Faculdade de Ciências Agrarias Universidade Federal da Grande Dourados (UFGD) Curso de Agronomia Centro Universitário da Fundação Educacional de Barretos Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Campus de Jaboticabal Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Campus de Jaboticabal

The aim of this study was to evaluate the quality attributes and properties of fillets from surubins (Pseudoplatystoma spp.) reared in cages and fishponds. The design of the study was completely randomized, with two treatments (cage and fishpond) and 16 replicates each. The fillets from fishes reared in cage and fishpond had a mean total weight of 134.71 ± 33.11 g and 151.56 ± 18.56 g, respectively. The following parameters were analyzed: pH, water retention capacity (WRC), color (L* brightness), (a* red), (b* yellow), and shear force (SF). The data were subjected to analysis of variance and the means were compared by Tukey’s and Mann-Whitney (nonparametric) tests. Statistically significant differences (p0.05) was detected between the treatments. A lower pH (6.17 ± 0.23) was observed in fillets from surubins reared in cage. As this is close to the isoelectric point of myofibrillar proteins, it reduces their net charge and, consequently, their capacity to retain water. Lower WRC of fillets obtained from fishes reared in cage (61.46 ± 1.62%) implies loss of nutritional value through the exudate released which results in drier fillets and compromised tenderness. In fillets from cage production, SF (1.06 ± 0.22 kgf) was higher than those from fishpond, i.e., the higher the shear force, the lower the tenderness of the fillet. On the basis of the observation that fillets from fishes reared in fishponds were more tender, this study confirmed that the quality of surubin fillets is influenced by the production system.

Every morphological, behavioral, or even developmental character expression of living beings is coded in its genotype and is expressed in its phenotype. Nevertheless, the interplay between phenotypic and ontogenetic plasticities, that is, the capability to manifest trait variations, is a current field of research that needs morphometric, numerical, or even mathematical modeling investigations. In the present work, we are searching for a phenotypic index able to identify the underlying correlation among phenotypic, ontogenetic, and geographic distribution of the evolutionary development of species of the same genus. By studying the case of Pseudoplatystoma fishes, we use their skin patterns as an auxiliary trait that can be reproduced by means of a reaction diffusion (RD) model. From this model, we infer the phenotypic index in terms of one of the parameters appearing in the mathematical equations. To achieve this objective, we perform extensive numerical simulations and analysis of the model equations and link the parameter variations with different environmental and physicochemical conditions in which the individuals develop, and which may be regulated by the ontogenetic plasticity of the species. Our numerical study indicates that the patterns predicted by a set of reaction diffusion equations are not uniquely determined by the value of the parameters of the equation, but also depend on how the process is initiated and on the spatial distribution of values of these parameters. These factors are therefore significant, since they show that an individual's growth dynamics and apparent secondary transport processes, like advection, can be determinant for the alignment of motifs in a skin pattern. Our results allow us to discern the correlation between phenotypic, ontogenetic, and geographic distribution of the different species of Pseudoplatystoma fishes, thus indicating that RD models represent a useful taxonomic tool able to quantify evolutionary indexes.

Made available in DSpace on 2018-12-11T17:06:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The presence of introgressive hybridization in the wild, especially that resulting from human interference, can have negative impacts on biodiversity. Genetic tools provide essential information for species and hybrid identification, facilitating the conservation of natural resources. Here, we tested a set of markers to precisely elucidate introgressive hybridization between Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum, two South American catfishes. New microsatellites showed high interspecific genetic divergence, and simulated data demonstrated the high power of STRUCTURE and NEWHYBRIDS for hybrid identification and classification, especially when all 11 nuclear markers were used. The investigation of real populations suggested that natural hybridization is rare. Otherwise, different hybridization scenarios were observed in two wild populations: one involving advanced backcrosses and the other involving high admixture. Our data represent the first detailed evaluation of genetic introgression between these species in Parana and Paraguay Basins and suggest that genetic contamination is occurring through F1 hybrids from aquaculture facilities. The results also provide a useful set of markers for monitoring escapees to aid in the conservation of the wild population and sustainable aquaculture. Additionally, species genotypic data are freely available to be used in the future as “parental species reference” in Bayesian methods assignments. Universidade Estadual Paulista (UNESP) Geneaqua Centro de Aquicultura da Unesp (CAUNESP) Centro Nacional de Pesquisa e Conserva��o de Peixes Continentais Instituto Chico Mendes de Conserva��o (CEPTA/ICMBio) Universidade de Santiago de Compostela (USC) Departamento de Biologia Universidade Estadual Paulista (UNESP), Av. Eng. Luiz Edmundo Carrijo Coube 14-01, Vargem Limpa Universidade Estadual Paulista (UNESP) Centro de Aquicultura da Unesp (CAUNESP) Departamento de Biologia Universidade Estadual Paulista (UNESP), Av. Eng. Luiz Edmundo Carrijo Coube 14-01, Vargem Limpa CNPq: 477703/2011-9 FAPESP: 477703/2011-9

This study developed a technique for the preparation of pâte from cachapinta (Pseudoplatystoma sp) waste. For this, frozen minced cachapinta fish was crushed in a mini cutter and homogenized with all other ingredients. The prepared pâte was stored in seamed and thermally treated cans (volume 170 g). Weight proportions of mean moisture, ash, protein, and lipid contents of the minced fish were 75.49, 1.00, 15.00, and 7.92 (g/100 g), respectively. The formulation of the developed pâte is in accordance with legislation for fish products. Cachapinta pâte is a product with high content of polyunsaturated fatty acids, low level of trans fat, and good indices of nutritional quality. Tests of sensory acceptance, purchase intent, and sensory attributes (except spreadability) averaged a score above 6.0, indicating acceptability of the product. Our study suggests that the potential of minced cachapinta for pâte production is high, and that it can contribute a value-added product to seafood consumption.

Most studies in nutrition for the South American catfish (surubim) were limited to the initial phase of development. However, it is clear that performance and nutrient utilization can change during the life stages of a fish. Therefore, this study aimed to evaluate the performance and nutrient utilization in juveniles of surubim fed diets varying in protein and energy levels. Two experiments were performed to test different levels of energy and protein in formulated diets. In the first experiment, surubim juveniles (89.2±4.8g) were fed five diets containing different levels of energy (18.0, 18.8, 19.6, 20.5, 21.3 MJ/kg). In the second experiment, juveniles (170.03±3.35g) were fed five diets containing different levels of protein (360, 400, 440, 480 and 520g/kg). The most favorable energy level for weight gain was 20.3 MJ/kg. The increasing energy levels provided a rise in fat and decrease in protein whole-body composition. The protein amount was between 360 to 400g/kg (383g/kg), which was adequate for performance and nutrient assimilation in surubim juveniles. A maior parte dos estudos a respeito dos aspectos nutricionais do surubim está limitada às primeiras fases de desenvolvimento. Entretanto, é claro que o desempenho e a utilização dos nutrientes podem mudar durante os diferentes estágios de desenvolvimento destes animais. Assim sendo, este estudo teve como objetivo avaliar o desempenho e a utilização de nutrientes em juvenis de surubim alimentados com dietas contendo níveis variáveis de energia e proteína. Dois experimentos foram realizados para testar os diferentes níveis de proteína e energia. No primeiro experimento, juvenis de surubim (89,2±4,8g) foram alimentados com cinco dietas contendo níveis diferentes de energia (18.0, 18.8, 19.6, 20.5, 21.3MJ/kg). No segundo experimento, os juvenis (170,03±3,35g) foram alimentados com dietas contendo cinco níveis de proteína (360, 400, 440, 480 e 520g/kg). O melhor nível de energia para ganho de peso foi 20,3 MJ/kg. O aumento dos níveis de energia levou a um incremento nos níveis de lipídeo e diminuição da proteína corporal. Níveis de proteína entre 360 a 400g/kg foram os mais adequados para o desempenho e utilização dos nutrientes em juvenis grandes de surubim.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:55:01Z No. of bitstreams: 1 S0001-37652013000100379.pdf: 433053 bytes, checksum: 2882f51e12f3310d6ee06a2d62361b51 (MD5) Made available in DSpace on 2013-08-22T18:55:01Z (GMT). No. of bitstreams: 1 S0001-37652013000100379.pdf: 433053 bytes, checksum: 2882f51e12f3310d6ee06a2d62361b51 (MD5) Previous issue date: 2013-03-05 Made available in DSpace on 2013-09-30T19:47:25Z (GMT). No. of bitstreams: 2 S0001-37652013000100379.pdf: 433053 bytes, checksum: 2882f51e12f3310d6ee06a2d62361b51 (MD5) S0001-37652013000100379.pdf.txt: 19414 bytes, checksum: 704131d28067aa620120a231010cf636 (MD5) Previous issue date: 2013-03-05 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:12:37Z No. of bitstreams: 2 S0001-37652013000100379.pdf: 433053 bytes, checksum: 2882f51e12f3310d6ee06a2d62361b51 (MD5) S0001-37652013000100379.pdf.txt: 19414 bytes, checksum: 704131d28067aa620120a231010cf636 (MD5) Made available in DSpace on 2014-05-20T15:12:37Z (GMT). No. of bitstreams: 2 S0001-37652013000100379.pdf: 433053 bytes, checksum: 2882f51e12f3310d6ee06a2d62361b51 (MD5) S0001-37652013000100379.pdf.txt: 19414 bytes, checksum: 704131d28067aa620120a231010cf636 (MD5) Previous issue date: 2013-03-05 A vitamina C é essencial para dietas de peixe porque muitas espécies não conseguem sintetizá-la. Esta vitamina é necessária par a formação de cartilagem e matriz óssea. Além disso, age como antioxidante e melhora as resposta do sistema imunológico. O presente trabalho investigou os efeitos da suplementação de vitamina C em dietas para alevinos de pintado (Pseudoplatystoma corruscans) pela incidência de deformidades na estrutura óssea e cartilaginosa. O ascorbil polifosfato (AP) foi utilizado como fonte de vitamina C em dietas para alevinos de pintado durante o período de três meses. Seis dietas foram formuladas: uma dieta controle (0 mg de vitamina C / kg) e cinco dietas 500, 1.000, 1.500, 2.000 e 2.500 mg de AP / kg. Os peixes alimentados sem suplementação de vitamina C apresentaram deformidades óssea na cabeça e mandíbula e fragilidade de nadadeiras. Assim, a dieta de 500 mg de AP/kg foi suficiente para prevenir a ocorrência de deformidades, e a ausência desta vitamina prejudica o desenvolvimento ósseo de juvenis de pintados. Vitamin C is essential for fish diets because many species cannot syntethize it. This vitamin is needed for bone and cartilage formation. Moreover, it acts as antioxidant and improve the immunological system. The present work investigated the effects of vitamin C diet supplementation to spotted sorubim (Pseudoplatystoma coruscans) fingerlings by frequency of bone and cartilage deformation. Ascorbyl poliphosphate (AP) was used as source of vitamin C in the diets for spotted sorubim fingerlings during three months. Six diets were formulated: one diet control (0 mg/kg of vitamin C) and 500, 1,000, 1,500, 2,000 and 2,500 mg AP/kg diets. Fishes fed without vitamin C supplementation presented bone deformation in head and jaws, and fin fragilities. Thus, 500 mg AP/kg diet was enough to prevent deformation and the lack of vitamin C supplementation worsening the development of fingerlings. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Tabuleiros Costeiros Universidade Federal do Pará (UFPA) Laboratório de Ictioparasitologia e Piscicultura UNESP Departamento de Zootecnia da Faculdade de Ciências Agrárias e Veterinárias UNESP Departamento de Zootecnia da Faculdade de Ciências Agrárias e Veterinárias

The aim of this study was to evaluate the immune response of hybrid surubim vaccinated by intraperitoneal injection and by immersion against Aeromonas hydrophila. Vaccine was prepared with formalin-inactivated A. hydrophila. Forty eight fishes (47±9g) were distributed in 12 tanks (4 fish / tank) in the following treatments (4 tanks / treatment): unvaccinated fish, vaccinated intraperitoneally and vaccinated by immersion. After 21 days, intraperitoneally vaccinated fishes showed the highest values of total protein and immunoglobulins, agglutination titer and serum antimicrobial activity. Lysozyme concentration in the serum was higher in the fishes vaccinated by immersion than unvaccinated fishes. Intraperitoneal vaccination induced the highest immune response and could be used to improve the fish resistance against motile Aeromonas.

Made available in DSpace on 2018-12-11T16:42:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-07-01 The presence of interspecific hybrid surubim (Pseudoplatystoma corruscans × Pseudoplatystoma reticulatum) in natural environments can put at risk the existence of the pure parental lineages. The aim of this study was to characterize the genetic variability of pure Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum individuals from rivers in the Paraná and Paraguay basins in Brazil. Seventy-six pure individuals of P. corruscans and 16 of P. reticulatum were evaluated with six microsatellite loci for both species, along with one species-specific locus each for P. corruscans and P. reticulatum. Loss of heterozygosity was confirmed, and preservation measures for P. corruscans and P. reticulatum are needed in order not to lose further genetic variation. In addition, we confirmed that these markers are useful for the management of pure stocks in natural environments, for fish breeding, and in genetic conservation and improvement programs for these species. Faculty of Exact Sciences and Technology Universidade Federal da Grande Dourados (UFGD) Faculty of Agricultural and Veterinary Science Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Faculty of Veterinary Medicine and Zootechnics Universidade Federal do Mato Grosso do Sul (UFMS) Faculty of Biological and Environmental Science Universidade Federal da Grande Dourados (UFGD) Faculty of Agricultural and Veterinary Science Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP)

The blood profile of hybrid fish was studied. Pseudoplatystoma (P. coruscans X P. reticulatum) were submitted to different stocking densities in recirculating water system in two distinct phases of production. Hemoglobin concentration (Hg), packed cell volume (PCV) and mean corpuscular hemoglobin concentration (MCHC) were evaluated. There was no difference between the studied densities. Hemoglobin concentration, PCV and MCHC remained within the normal range for teleost fish.

INTRODUCTION: the fishing activity throughout the Upper Paraguay River Basin has huge financial and biological importance. This retrospective study investigated the occurrence of injuries caused by fish of the Pseudoplatystoma genus (spotted catfish or pintado and striped catfish or cachara) in professional fishermen of the Pantanal of Mato Grosso do Sul State. METHODS: we collected information through a questionnaire, showing that fishing is carried out by workers with low level of education, mainly adults or seniors with low financial gains. RESULTS: in Miranda town, 126 of 315 fishermen were interviewed and 38 individuals reported injuries (30.16%). In Corumbá town, 355 of 627 fishermen were interviewed, and 111 (56,61%) reported injuries. The lacerated lesions were the most common, associate with edema, erythema, radiating pain to the root of the limb, paresthesias and local necrosis. More rarely, they reported the occurrence of fever, cardiac arrhythmias and cold sweating. These manifestations may be associated with late secondary infections or envenomations caused by the toxins in the stingers of the fish. Many questionable and inappropriate treatments are used, sometimes aggravating the injuries. CONCLUSIONS: the freshwater professional fishermen need guidance on first aid measures and prevention of accidents caused by these venomous fish. RESUMO INTRODUÇÃO: a atividade pesqueira no alto Rio Paraguai tem grande impacto financeiro e biológico. Este estudo retrospectivo investigou a ocorrência de acidentes causados por peixes do gênero Pseudoplatystoma (pintados e cacharas) em pescadores do Pantanal do Mato Grosso do Sul. MÉTODOS: obtivemos as informações através de um questionário, que mostrou que a pesca é feita por trabalhadores com baixo nível de educação, principalmente adultos ou idosos com baixos ganhos financeiros. RESULTADOS: no município de Miranda, 126 dos 315 pescadores foram entrevistados, com 38 relatando acidentes (30.16%). Em Corumbá, 355 de 627 pescadores foram entrevistados, com 111 acidentados. As lesões laceradas foram mais comuns, associadas com edema, eritema, dor irradiada para a raiz do membro, parestesias e necrose local. Mais raramente, reportaram a ocorrência de fenômenos sistêmicos, como febre, arritmias e sudorese fria. Estas manifestações podem estar relacionadas com infecções secundárias. Muitos tratamentos questionáveis e inapropriados são usados, por vezes agravando o quadro. CONCLUSÕES: os pescadores profissionais de água doce necessitam de orientação sobre primeiros socorros e medidas de prevenção de acidentes causados por estes peixes.

Made available in DSpace on 2016-07-07T12:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2014. Added 1 bitstream(s) on 2016-07-07T12:43:07Z : No. of bitstreams: 1 ISSN2317-269X-2014-02-03-64-70.pdf: 548641 bytes, checksum: 2215a840fade163221753a07d96021e4 (MD5) Marcadores moleculares (PCR-Multiplex de genes nucleares e mitocondriais) foram uti- lizados para verificar a identidade molecular de filés de peixe comercializados como pintado (Pseudoplatystoma corruscans) com base em polimorfismos de regiões do DNA nuclear (genes RAG2, globina e EF1) e mitocondriais (16S) para verificar se os filés per- tenciam a espécie pura de pintado ou se eram híbridos derivados do cruzamento entre cachara (Pseudoplatystoma reticulatum) e pintado (Pseudoplatystoma corruscans). Os filés analisados (n = 29) apresentaram genes nucleares de ambas espécies P. corruscans e P. reticulatum, e desta forma, foram identificados como híbridos interespecíficos ou F1 (primeira geração filial) do tipo “cachapinta” resultante do cruzamento entre uma fêmea de cachara e um macho de pintado. Estes resultados mostram que o monitora- mento da comercialização de filés de peixe é fundamental para identificar situações onde existem diferenças entre as espécies comercializadas e as informações declaradas no rótulo. Espécies em que a hibridação tem sido frequentemente realizada como é o caso do pintado e da cachara, merecem atenção especial. Nuclear and mitochondrial genes were used as molecular markers for verifying the iden- tity of fish fillets marketed as pintado (Pseudoplatystoma corruscans). Based on THE polymorphisms of nuclear DNA (RAG2, globin, and EF1 genes) and mitochondrial regions (16S), we examined whether the fillets originated from inbred species of pintado or from hybrids derived from crosses between cachara (P. reticulatum) and pintado. Nuclear genes from both species were detected in the analyzed fillets (n = 29). This clearly iden- tified these fish as interspecific hybrids (or F1/first filial generation) of the type “cacha- pinta,” resulting from a cross between female cachara and male pintado. These results demonstrate that monitoring fish fillet trading is crucial for detecting discrepancies between the marketed species and related information declared on the label. Species that are frequently hybridized, such as pintado and cachara, require special attention. Universidade Federal Fluminense (UFF), Niterói, RJ, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Faculdade de Ciências (FC), Departamento de Ciências Biológicas, Bauru, SP, Brasil Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Rio de Janeiro, RJ, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Faculdade de Ciências (FC), Departamento de Ciências Biológicas, Bauru, SP, Brasil

The genus Pseudoplatystoma includes catfish species distributed throughout the fresh waters of South America. These species are important fisheries resources and play a significant ecological role due to their piscivorous and migratory habits. The taxonomy of this genus is still debated: traditionally, only three species have been recognised, but recently, this number was raised to eight. The validity of these eight morphospecies, however, was not confirmed by two subsequent molecular phylogenetic studies, which identified either five or four main clades. In this study, we focused on the two morphospecies restricted to the Orinoco basin, P. metaense and P. orinocoense, which have been assigned to either the same or different clades in previous studies. We carried out cytogenetic analyses to describe their unknown karyotypes and to look for cytotaxonomic markers. We also analysed their mitochondrial sequences in order to assign the sampled specimens to the previously identified molecular clades. Th...

Karyotypic data are presented for four species of fish belonging to the Pimelodidae family. These species show a conserved diploid number, 2n = 56 chromosomes, with different karyotypic formulae. The analyzed species showed little amount of heterochromatin located preferentially in the centromeric and telomeric regions of some chromosomes. The nucleolus organizer regions activity (Ag-NORs) and the chromosomal location of ribosomal genes by fluorescent in situ hybridization (FISH), with 18S and 5S probes, showing only one chromosome pair marked bearer of ribosomal genes, the only exception was Pimelodus britskii that presented multiple NORs and syntenic location of the 18S and 5S probes. Non-Robertsonian events, as pericentric inversion and NORs duplication are requested to explain the karyotype diversification in Pseudoplatystoma from the rio Paraguay (MS), Pimelodus from the rio Iguaçu (PR), Sorubim from the rio Paraguay (MS) and Steindachneridion from the rio Paraíba do Sul (SP). The obtained data for the karyotype macrostructure of these species corroborates a conserved pattern observed in Pimelodidae. On the other hand, interspecific variations detected by molecular cytogenetics markers made possible cytotaxonomic inferences and differentiation of the species here analyzed.Dados cariotípicos são apresentados para quatro espécies da família Pimelodidae. Todas apresentaram o mesmo número diploide, 2n = 56 cromossomos, com diferenças nas fórmulas cariotípicas. As espécies aqui analisadas mostraram pouca quantidade de heterocromatina localizada preferencialmente na região centromérica e telomérica de alguns cromossosmos do complemento cariotípico. As regiões organizadoras de nucléolo (Ag-RONs) e a localização dos genes ribossomais pela hibridização in situ fluorescente (FISH), com sondas 18S e 5S, evidenciaram somente um par cromossômico marcado portador de genes ribossomais, à exceção de Pimelodus britskii que apresentou NORs múltiplas e localização sintênica das sondas 18S e 5S. Eventos não-Robertsonianos, como inversão pericêntrica e duplicação das NORs são requeridos para explicar a diversificação cariotípica em Pseudoplatystoma do rio Paraguai (MS), Pimelodus do rio Iguaçu (PR), Sorubim do rio Paraguai (MS) e Steindachneridion do rio Paraíba do Sul (SP). Os dados obtidos para a macroestrutura cariotípica destas espécies corrobora um padrão conservado observado na família Pimelodidae. Por outro lado, evidências de variações interespecíficas pelos marcadores de citogenética molecular empregados possibilitam inferências citotaxonômicas e diferenciação das espécies aqui analisadas.

Pseudoplatystoma corruscans (Spix and Agassiz, 1829) and Pseudoplatystoma reticulatum (Eingenmann and Eigenmann, 1889) are large migratory catfishes of high biological importance and great commercial value in South America. Because fertile crossbreeds can be artificially produced in hatcheries, a high genetic proximity between these two Pimelodidae species is conceivable. Possible escape of crossbred specimens from pisciculture stations is a serious environmental concern. Despite their importance, knowledge of P. corruscans and P. reticulatum biology, ecology, population diversity and genetics is limited. In the present work, the genetic divergence between P. corruscans and P. reticulatum populations from the Paraná River Basin was analyzed on the basis of polymorphisms in ISSR fragments and in the hypervariable sequence of the mitochondrial DNA (mtDNA) control region. Estimates of intraspecific haplotype (h > 0.5) and nucleotide diversities (π < 0.01) indicate that P. corruscans and P. reticulatum have survived a historical population decline, followed by a demographic expansion. The interspecific polymorphisms within the mtDNA control region and ISSR fragments were suitable as diagnostic molecular markers and could be used to discriminate the two species. A unique Pseudoplatystoma specimen, captured in the Upper Paraná River Floodplain, was identified by these DNA diagnostic markers as a hybrid P. reticulatum x P. corruscans, which possibly escaped from pisciculture. The integrity of the natural population of P. corruscans in the Upper Paraná River is at risk of genetic introgression or homogenization due to the presence of hybrids and the transposition of P. reticulatum upstream through the Canal da Piracema at Itaipu Dam. Data presented herein improve the understanding of the genetic relatedness between P. corruscans and P. reticulatum and represent potential tools for future programs of conservation and surveillance of genetic introgression events and the genetic integrity of these populations. Pseudoplatystoma corruscans Spix e Agassiz, 1829 e Pseudoplatystoma reticulatum Eigenmann e Eigenmann, 1889 são peixes migratórios de grande porte, com alta importância biológica e elevado valor comercial na América do Sul. Híbridos férteis são obtidos em cativeiro e, portanto, é esperada alta proximidade genética entre essas duas espécies de Pimelodidae. Escapes de espécimes híbridos a partir de estações de piscicultura representam um sério problema ambiental. Apesar da sua importância, conhecimentos sobre a biologia, ecologia, diversidade de populações e genética de P. corruscans e P. reticulatum são escassos. No presente trabalho, foi avaliada a divergência genética entre P. corruscans e P. reticulatum da Bacia do Rio Paraná, com base em fragmentos ISSR e na seqüência D-loop do DNA mitocondrial (mtDNA). As estimativas das diversidades intra-específicas haplotípica (h > 0,5) e nucleotídica (π < 0,01) evidenciaram que P. corruscans e P. reticulatum sobreviveram a um declínio populacional histórico, seguido de expansão demográfica. Os polimorfismos interespecíficos no mtDNA e nos fragmentos ISSR foram eficientes para diagnósticos e discriminaram as duas espécies. Um espécime de Pseudoplatystoma capturado na planície de inundação do Alto Rio Paraná foi identificado com esses marcadores moleculares como híbrido P. reticulatum x P. corruscans, que possivelmente escapou de psicicultura. A integridade da população de P. corruscans no Alto Rio Paraná está ameaçada, por introgressão ou homogeneização genética, pela presença de híbridos e pela transposição para montante de P. reticulatum através do Canal da Piracema em Itaipu. Os dados apresentados constituem um avanço na compreensão do parentesco entre P. corruscans e P. reticulatum e representam ferramentas em potencial para programas de conservação biológica, incluindo o monitoramento de introgressão e de integridade genética das populações.

CAPES/CNPq/FINEP/SUDAM. Universidade Federal do Par?. Departamento de Qu?mica. Bel?m, PA, Brazil. Universidade Federal do Par?. Departamento de Qu?mica. Bel?m, PA, Brazil. Universidade de S?o Paulo. Instituto de Pesquisas Energ?ticas e Nucleares. Grupo de Caracteriza??o Isot?pica. S?o Paulo, SP, Brazil. Universidade Federal do Par?. Departamento de Qu?mica. Bel?m, PA, Brazil. Minist?rio da Sa?de. Funda??o Nacional de Sa?de. Instituto Evandro Chagas. Laborat?rio de Ecologia Humana e Meio Ambiente. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Funda??o Nacional de Sa?de. Instituto Evandro Chagas. Laborat?rio de Ecologia Humana e Meio Ambiente. Ananindeua, PA, Brasil. Universidade Federal do Par?. Departamento de Qu?mica. Bel?m, PA, Brazil. The environmental exposure to mercury by riverine and Indian communities can occur through the ingestion of fish and products contaminated by mercury compounds. The present study aims to evaluate the total mercury concentration in the different fish species most consumed in the municipality of Itaituba, Tapaj?s river basin, where there are intense gold-mining activities. These fish samples were analyzed by atomic absorption spectrophotometry by cold vapor technique, Automatic Mercury Analyzer HG-3500. The largest mercury concentrations were found in the carnivorous species ranging from 112.4 to 2250 microg/g, while the detritivorous, herbivorous and omnivorous species presented total mercury levels ranging from 3.2 to 309.8 microg/g, which is below the limit established by the World Health Organization. This paper also reports and identifies which species are more polluted and present a statistical relationship among concentration and weight of the carnivorous species studied in detail, Brachyplatystoma flavicans (dourada) (r2 = 0.691) and Pseudoplatystoma sp. (surubim) (r2 = 0.654).

Aeromonas has been described as an emergent foodborne pathogen of increasing importance. In this study, we report that 48% of 50 Pintado fish samples collected at the retail market of São Paulo city were positive for Aeromonas sp, as detected by the direct plating method. When the presence/absence method was used, the positivity was 42%. A. caviae was the most frequent species, followed by A. hydrophila and A. sobria. Production of cytotoxic enterotoxin, observed in suckling mouse assay, was detected in 67% of A. sobria strains, in 60% of A. hydrophila strains and in 40% of A. caviae strains. In vitro tests, performed with HEp-2 cells, showed that 88% of A. hydrophila, 27% of A. sobria and 13% of A. caviae strains were positive for this toxin. The in vivo production of cytotonic enterotoxin, tested after heating the filtrates at 56ºC for 20 minutes, was detected in 17% of A. sobria, in 10% of A. caviae and in none of A. hydrophila strains in vivo. All analyzed strains did not alter HEp-2 cells. 20% and 16% of A. sobria and A. caviae isolates, respectively, presented capacity to adhere to HEp-2 cells. In counterpart, invasion of HEp-2 cells was not observed in any isolate. The Aeromonas isolates were sensitive to the majority of the antimicrobiol agents tested.Bactérias do gênero Aeromonas têm sido descritas como patógenos emergentes de importância crescente em alimentos. Neste estudo, relatamos que 48% das amostras de peixe "Pintado" coletado no comércio de São Paulo, foram positivas para Aeromonas sp quando isoladas pelo método de plaqueamento direto. Quando o método Presença/Ausência foi utilizado, a porcentagem de positividade foi de 42%. A. caviae foi a espécie mais freqüente, seguida por A. hydrophila e A. sobria. Produção de enterotoxina citotóxica, determinada em camundongos recém-nascidos, foi observada em 67% das cepas de A. sobria, em 60% das de A. hydrophila e em 40% das de A. caviae. No teste in vitro em células HEp- 88% das cepas de A. hydrophila, 27% das cepas de A. sobria e 13% das cepas de A. caviae revelaram-se positivas. Com relação a produção de enterotoxina citotônica, testada após o aquecimento do sobrenadante a 56ºC por 20 minutos, 17% das cepas de A. sobria, 10% das de A. caviae e nenhuma das de A. hydrophila foram positivas in vivo e para todas as cepas analisadas, os testes foram negativos em cultura de célula HEp-2. Quanto a capacidade de adesão, 20% das 5 cepas de A. sobria e 16% das 20 cepas de A. caviae aderiram a células HEp-2. A capacidade de invasão em células HEp-2 não foi detectada em nenhuma das cepas testadas. As cepas isoladas foram sensíveis a maior parte dos antimicrobianos testados.

In this study we verified data of water temperatures collected by CORSAN-RS from 1996 to 2004 in several cities of the state of Rio Grande do Sul, southern Brazil, and analyzed the possibility of raising the most cultivated fish species in Brazil. The water temperature from 1996 to 2004 was 16 to 28ºC in summer, 17 to 23ºC in fall, 14 to 17ºC (down to 9ºC in the coldest months) in winter and 14 to 21ºC in spring. Native species of this state, such as silver catfish (Rhamdia quelen), traíra (Hoplias malabaricus), dorado (Salminus brasiliensis), pintado (Pimelodus maculatus), as well as carps (family Cyprinidae), are resistant to the low winter temperatures. These species have a lower growth rate in coldest months (winter/spring) but a good development in warmer months (summer/fall), reaching a satisfactory performance throughout the year. In the periods of more intense cold, mortality of some introduced species, such as surubim from Amazon Basin (Pseudoplatystoma sp.), pirapitinga (Piaractus brachypomus), pirarucu (Arapaimas gigas), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and Nile tilapia (Oreochromis niloticus) may occur. In addition, as most tropical species have a thermal range for growth and reproduction between 20 to 28ºC, some species may have poor development even in fall. Therefore, water temperature in this state should be considered in the choice of fish species to be cultivated. Neste estudo verificaram-se dados de temperaturas de água coletados pela CORSAN-RS de 1996 a 2004, em várias cidades do estado do Rio Grande Sul, sul do Brasil, e analisou-se a possibilidade de criação das principais espécies de peixe cultivadas no Brasil. A temperatura da água de 1996 a 2004 foi de 16 a 28ºC no verão, de 17 a 25ºC no outono, 14 a 17ºC (chegando a 9ºC nos meses mais frios) no inverno e 14 a 21ºC na primavera. Espécies nativas deste estado, como o jundiá (Rhamdia quelen), traíra (Hoplias malabaricus), dourado (Salminus brasiliensis), pintado (Pimelodus maculatus), assim como as carpas (família Cyprinidae), são resistentes às baixas temperaturas do inverno. Estas espécies apresentam uma menor taxa de crescimento nos meses mais frios (inverno/primavera), mas um bom desenvolvimento em meses mais quentes (verão/outono), alcançando um desempenho satisfatório durante o ano. Nos períodos de frios mais intensos pode ocorrer uma intensa mortalidade de algumas espécies introduzidas, como o surubim da Bacia Amazônica (Pseudoplatystoma sp.), pirapitinga (Piaractus brachypomus), pirarucu (Arapaimas gigas), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) e tilápia nilótica (Oreochromis niloticus). Além disso, como a maioria das espécies tropicais apresenta sua faixa térmica para crescimento e reprodução entre 20 a 28ºC, algumas espécies podem ter um baixo desenvolvimento também no outono. Portanto, a temperatura da água deste estado deve ser considerada na escolha das espécies de peixes a serem cultivadas.