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Sample records for pirapitinga piaractus brachypomus

  1. Straminipilous organisms growing on herbivorous pirapitinga (Piaractus brachypomus and carnivorous piranha (Pygocentrus nattereri from Poland Organismos stramenophila em crescimento na herbívora pirapitinga (Piaractus brachypomus e na carnívora piranha (Pygocentrus nattereri da Polônia

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    B. Czeczuga

    2010-05-01

    Full Text Available We investigated the growth of straminipilous organisms on the skin, muscles and liver of herbivorous pirapitinga (Piaractus brachypomus and carnivorous piranha (Pygocentrus nattereri in water of three different eutrophication levels. Sixteen straminipilous organism species were found growing on the investigated body parts of both species of fish used as baits. The higher number of species was found on the baits of carnivorous species (15 when compared with the ones from the herbivorous pirapitinga (10 species. The highest number of straminipilous organisms species developed on the skin of both species of fish. The highest number of species of straminipilous organisms was observed growing in the water of the BiaBa river (middle eutrophication, while the lowest number occurred in the baits of vessels with water from the Dojlidy pond (low eutrophication.Investigamos o crescimento de organismos stramenophila sobre a pele, músculos e fígado da herbívora pirapitinga (Piaractus brachypomus e da carnívora piranha (Pygocentrus nattereri em águas de três diferentes níveis de eutrofização. Dezesseis espécies de organismos stramenophila foram encontradas crescendo sobre as partes do corpo investigadas de ambas as espécies de peixes utilizadas como cobaias. O maior número de espécies foi encontrado em cobaias de espécies carnívoras (15, quando comparado com o da herbívora pirapitinga (10 espécies. A maioria das espécies de organismos stramenophila desenvolveu-se sobre a pele de ambas as espécies de peixes. O maior número de espécies de organismos stramenophila foi observado em crescimento nas águas do rio BiaBa (eutrofização do meio, enquanto o número mais baixo ocorreu em cobaias de vasos com água do lago de Dojlidy (eutrofização baixa.

  2. Out-of-season sperm cryopreserved in different media of the Amazonian freshwater fish pirapitinga (Piaractus brachypomus).

    Science.gov (United States)

    Nascimento, A F; Maria, A N; Pessoa, N O; Carvalho, M A M; Viveiros, A T M

    2010-04-01

    The pirapitinga (Piaractus brachypomus) is a freshwater fish that inhabits the Amazon and Orinoco River basins. The use of cryopreserved sperm has been considered to facilitate procedures during the artificial reproduction. The aim of the present study was to develop a freezing protocol for pirapitinga sperm collected outside the spawning season. Sperm samples were diluted in four freezing media prepared by a combination of two extenders (glucose and BTS-Beltsville Thawing Solution) and two cryoprotectant agents (DMSO and methylglycol) loaded into 0.5-mL straws, frozen in a nitrogen-vapor shipping dewar (dry-shipper) and stored in liquid nitrogen at -196 degrees C. Post-thaw sperm motility was evaluated both subjectively using a light microscope and by a computer-assisted sperm analyzer (CASA). Curvilinear, average path and straight-line velocities were also determined. There were no differences (P>0.05) in post-thaw sperm motility between evaluations performed subjectively and using the CASA. Sperm samples cryopreserved in glucose-methylglycol yielded the greatest post-thaw sperm motility (81%) and fastest sperm velocities when compared to the samples frozen in the other three media (Partificial reproduction procedures, as only females will need handling for hormonal induction and gamete collection during the spawning season. Although the CASA system provides precise data on sperm motility, the subjective evaluation is practical and can be conducted by well-trained personnel at commercial fish farms as an acceptable evaluation of sperm quality. Copyright 2009 Elsevier B.V. All rights reserved.

  3. Índices de rendimiento corporal en morocoto Piaractus brachypomus cultivado en sistemas Biofloc

    OpenAIRE

    Abad, Darwin; Rincón, David; Poleo, Germán

    2014-01-01

    El objetivo principal de esta investigación fue determinar los índices de rendimiento corporal(canal, viscerosomático, hepatosomático y escamas) del morocoto Piaractus brachypomus cultivado en sistemas Biofloc. Mil trescientos juveniles de morocoto con talla promedio de 10±0,2 cm y 15±3,1 g de peso, fueron sembrados en cinco tanques circulares de 15m³ a una densidad de 17,3 organismos/m³. Los peces fueron alimentados a saciedad aparente con alimento comercial (28% PC) durante un periodo de 21...

  4. Estudos para Composição de uma Dieta Referência Semipurificada para Avaliação de Exigências Nutricionais em Juvenis de Pirapitinga, Piaractus brachypomus (Cuvier, 1818

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    Vásquez-Torres Wálter

    2002-01-01

    Full Text Available Foram realizados dois experimentos com o objetivo de definir uma dieta referência para estudos de exigências nutricionais em Piaractus brachypomus. No primeiro experimento, foram testadas quatro dietas com ingredientes semipurificados (H-440 com 47% PB, C-102 com 41% PB, NRC com 37% PB e IALL-1 com 32% de PB e uma dieta controle (32% de PB com ingredientes comuns. No segundo experimento, foi usada a dieta IALL-1, como base para a formulação de três dietas experimentais. A dieta 2 foi suplementada com vitamina C e uma pré-mistura de macrominerais, enquanto na dieta 3 o óleo vegetal foi substituído por óleo de peixe. O ganho de peso foi usado como critério básico para medir os efeitos das dietas, sendo também considerados consumo de alimento, taxa específica de crescimento (SGR, conversão alimentar aparente (FCR, eficiência de utilização da proteína (PER e retenção de proteína (%PPV e de energia (%RE. Entre as dietas semipurificadas, o melhor desempenho de crescimento e de utilização dos nutrientes foi observado para as dietas NRC e IALL-1, que não diferiram entre si. No segundo experimento, o grupo de peixes alimentados com a dieta 2 apresentou crescimento 42% maior que o observado com as dietas sem suplementação. As outras variáveis analisadas, FCR, SGR, PER e %PPV, também foram significativamente melhoradas. Os resultados em conjunto indicam que a dieta IALL-1 suplementada com macrominerais e vitamina C pode ser considerada adequada como dieta referência semipurificada para estudos de nutrição de Piaractus brachypomus.

  5. Estudio histológico del sistema digestivo en diferentes estadios de desarrollo de la cachama blanca (Piaractus brachypomus

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    Miguel Ángel Mendoza R.

    2013-06-01

    Full Text Available La cachama blanca (Piaractus brachypomus es la segunda fuente de producción piscícola en Colombia, después de la tilapia roja (Oreochomi ssp. y antes de la trucha arcoíris (Oncorhynchus mykiss. Se destaca, además, como una de las especies con mayor potencial productivo en el país. Se realizó el estudio histológico del sistema digestivo de la Piaractus brachypomus a fin determinar la morfología normal en diferentes estadios de desarrollo. Para ello se clasificaron los animales según la edad, el tamaño y el peso en ovas embrionadas, larvas con saco vitelino, alevinos después de reabsorción de saco vitelino, juveniles (3-5 cm, 5-7 cm, 10 cm, 15 cm y adultos (300 g. La fijación de los tejidos se realizó en formaldehído al 3,7 % y se describió microscópicamente cavidad bucal, faringe, esófago, estómago, ciegos pilóricos, intestinos y las glándulas anexas, hígado y páncreas. Por último, se describió macroscópicamente la organización anatómica de este sistema.

  6. Influência da primeira alimentação na larvicultura e alevinagem do yamú Brycon siebenthalae (Characidae - DOI: 10.4025/actascianimsci.v25i1.2092 First feeding influence on yamú, Brycon siebenthalae (Characidae larval rearing - DOI: 10.4025/actascianimsci.v25i1.2092

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    Sandra Pardo-Carrasco

    2003-04-01

    Full Text Available Para avaliar a influência da primeira alimentação na alevinagem do yamú, Brycon siebenthalae, no Instituto de Acuicultura/Universidad de Los Llanos (Villavicencio, Colômbia, foram desenvolvidos dois experimentos. No experimento 1, testaram-se, durante vinte e quatro horas, diferentes tipos de alimento vivo como primeira alimentação das pós-larvas (PL de yamú: náuplios de Artemia sp. (NA, zooplâncton silvestre (ZS e larvas de pirapitinga (LP (Piaractus brachypomus. No tratamento controle as pós-larvas foram mantidas em jejum. O alimento que proporcionou melhores resultados em ganho de peso e comprimento total foi larvas de pirapitinga (p Two experiments were carried out at Instituto de Acuicultura de Los Llanos/Universidad de Los Llanos (Villavicencio, Colômbia to evaluate first feeding influence on yamú larval rearing. In the first experiment, the following prey types were tested to first feeding for yamú larvae during 24 hours: Artemia sp. nauplii, wild zooplankton and pirapitinga (Piaractus brachypomus larvae. In the control yamú larvae were subjected to starvation. Pirapitinga larva was the prey item that offered the best results for weight and total length gain (p < 0.05. In the second experiment, yamú larvae performance was compared when stocked into fertilized ponds during 15 days either at the onset feeding or after first feeding with pirapitinga larvae prey item. Survival rate was lower in the larvae that were stocked into rearing ponds at the onset of feeding (13.4% when compared to survival of yamú larvae that were stocked after receiving pirapitinga larvae (74.1%. These results indicate that the use of pirapitinga larvae at first feeding increases performance of yamú larval rearing.

  7. Estandarización de un proceso de extracción de colágeno a partir de los residuos de fileteo de tilapia (Oreochromis sp) y cachama (Piaractus brachypomus) / Standardization of a process for extracting collagen from filleting waste from tilapia (Oreochromis sp) and cachama (Piaractus brachypomus)

    OpenAIRE

    Serrano Gaona, Jenifer Carolina

    2011-01-01

    Se estandarizó un proceso de extracción y purificación de colágeno ácido soluble a partir de pieles de tilapia (Oreochromis sp) y de cachama (Piaractus brachypomus) utilizando análisis estadísticos. Los resultados indicaron que el rendimiento de colágeno ácido soluble fue de 33,3% en base seca. El patrón de alto peso molecular utilizado para SDS – PAGE reveló que el colágeno obtenido de pieles de tilapia o de pieles de cachama es colágeno tipo I. La temperatura de desnaturalización (Td) del c...

  8. Análisis proximal, evaluación microbiológica y sensorial de carnes para hamburguesas elaboradas con cachama blanca (Piaractus brachypomus) y soya (Glycine max) texturizada

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    Oscar García; Iria Acevedo; Jorge Ruiz Ramírez

    2013-01-01

    La cachama blanca (Piaractus brachypomus) es una especie económicamente importante en la acuicultura continental de América Latina y una alternativa nacional de producción de pescado para la piscicultura, la industria y el consumo. El objetivo del presente trabajo de investigación fue caracterizar mediante análisis proximal, evaluación microbiológica y sensorial, carnes para hamburguesas elaboradas con pulpa de cachama y diferentes inclusiones porcentuales de harina de soya texturizada (HST) ...

  9. Physicochemical Evaluation of Cachama Fillets (Piaractus brachypomus Preserved with Propolis during Storage / Evaluación Fisicoquímica de Filetes de Cachama (Piaractus brachypomus Preservados con Propóleos durante el Almacenamiento

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    Héctor Suárez Mahecha

    2014-03-01

    Full Text Available The bioactive compounds that propolis containspresent diverse components that can diminish the deterioration of compounds such as fat and certain microorganisms that can affect fish fillets during refrigerated storage. The aim of this study was to evaluate the preserving capacity of ethanol extracts of propolis (EEP in cachama fish fillets (Piaractus brachypomus. The treatments carried out were: (1 ethyl alcohol (96% as the control; (2 0.8% EEP; (3 1.2% EEP; and (4 liquid smoke. Analyses were carried out for total volatile base nitrogen (TVBN, thiobarbituric acid reactive species-TBARS, pH and water loss for 0, 8, 16 and 24 days of storage at 4 ºC with vacuum packaging. The results presented the highest values of the TBARS and TVBNanalyses for the liquid smoke treatment and the lowest values for the EEP treatments, demonstrating a significant difference between the treatments (P<0.05; however, the best water retention capacity was seen in the fillets treated with liquid smoke. The results for pH did not present significant differences between the treatments (P>0.05 during the storage period. The results suggest that EEP can preserve physicochemical characteristics during the shelf life of refrigerated, vacuum packed cachama fillets. / Los compuestos bioactivos contenidos en propóleos presentan diversos componentes, que pueden disminuir el deterioro de compuestos como la grasa, y la cantidad de ciertos microorganismos, que pueden afectar filetes de pescado durante el almacenamiento bajo refrigeración. El objetivo de este trabajo fue evaluar la capacidad conservante de extractos etanólicos de propóleos (EEP sobre filetes del pescado cachama (Piaractus brachypomus. Los tratamientos realizados fueron: (1 alcohol etílico (96% como control; (2 EEP 0,8%; (3 EEP 1,2% y (4 humo líquido. Fueron realizados análisis para bases volátiles totales (BVTN, especies reactivas al ácido tiobarbitúrico-TBARS, pH y pérdida de agua

  10. Validación del Protocolo de Reproducción de Colossoma macropomum, Piaractus brachypomus y Prochilodus nigricans en Condiciones Controladas

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    Lorgio Verdi Olivares

    2014-06-01

    Full Text Available Protocolos aplicados a las diferentes etapas de la reproducción  inducida: tratamiento hormonal, incubación, manejo de larvas, y manejo de alevines en los peces de consumo humano Colossoma macropomum (gamitana, Piaractus brachypomus (paco y Prochilodus nigricans (boquichico fueron evaluados en el marco del proyecto UNAP “Cátedra CONCYTEC en Acuicultura Tropical” con el propósito de establecer los adecuados procedimientos en la búsqueda de una óptima productividad acuícola y una mejor rentabilidad económica en Loreto. Con este objetivo se utilizaron como inductores: para gamitana, Pituitaria de Carpa con dosis total de 6,0 mg/kg en hembras y 2,0 mg/kg en machos; Para machos y hembras de paco, Conceptal en dosis total de 2,6 ml/kg en hembras y 1,0 ml/kg en machos; y para boquichico, Pituitaria de Carpa con dosis total de 4,0 mg/kg en hembras y 2,0 mg/kg en machos. El desove se produjo en 11±2 horas; la eclosión ocurre después de 22 horas a partir de la fecundación, con tasas promedios superiores al 70% y tasas de sobrevivencia, aún cundo por debajo del 50%, garantiza una alta producción de alevines.

  11. Validación del Protocolo de Reproducción de Colossoma macropomum, Piaractus brachypomus y Prochilodus nigricans en Condiciones Controladas

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    Lorgio Verdi-Olivares

    2014-07-01

    Full Text Available Protocolos aplicados a las diferentes etapas de la reproducción  inducida: tratamiento hormonal, incubación, manejo de larvas, y manejo de alevines en los peces de consumo humano Colossoma macropomum (gamitana, Piaractus brachypomus (paco y Prochilodus nigricans (boquichico fueron evaluados en el marco del proyecto UNAP “Cátedra CONCYTEC en Acuicultura Tropical” con el propósito de establecer los adecuados procedimientos en la búsqueda de una óptima productividad acuícola y una mejor rentabilidad económica en Loreto. Con este objetivo se utilizaron como inductores: para gamitana, Pituitaria de Carpa con dosis total de 6,0 mg/kg en hembras y 2,0 mg/kg en machos; Para machos y hembras de paco, Conceptal en dosis total de 2,6 ml/kg en hembras y 1,0 ml/kg en machos; y para boquichico, Pituitaria de Carpa con dosis total de 4,0 mg/kg en hembras y 2,0 mg/kg en machos. El desove se produjo en 11±2 horas; la eclosión ocurre después de 22 horas a partir de la fecundación, con  tasas promedios superiores al 70% y tasas de sobrevivencia, aún cundo por debajo del 50%, garantiza una alta producción de alevines.

  12. Parásitos de alevinos de gamitana (Colossoma macropomum y paco (Piaractus brachypomus cultivados en el C.I. Quistococha, Loreto, Perú

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    Fernando Alcántara Bocanegra

    2015-06-01

    Full Text Available En acuicultura, los peces son susceptibles al ataque de virus, bacterias, hongos y ectoparásitos. Estos organismos se tornan en un serio problema cuando los peces se encuentran con bajas defensas naturales, se crían en altas densidades y/o se altera drásticamente la calidad de agua. El objetivo del presente estudio fue identificar la fauna de parásitos presentes en alevinos de paco (Piaractus brachypomus y gamitana (Colossoma macropomum provenientes de estanques del Centro de Investigación Quistococha del IIAP. Un total de 30 ejemplares de cada especie fueron examinados a través de la preparación de frotis fresco de branquias, piel, aletas y tubo digestivo. Entre las dos especies estudiadas, gamitana demostró una mayor prevalencia de infestación, mayor intensidad de parásitos y mayor índice de infestación parasitaria. Los alevinos de paco mostraron una mayor resistencia a la propagación y al ataque de parásitos. Se identificaron monogeneos de las familias Dactylogyridae y Gyrodactylidae, solo en gamitana, mientras que el protozoo ciliado Trichodina se halló exclusivamente en paco. Los parásitos identificados no causaron ninguna mortalidad en los peces.

  13. EVALUACIÓN DE NUEVA TECNOLOGÍA PARA MITIGAR LAS ESPINAS INTRAMUSCULARES EN FILETES DE CACHAMA Piaractus brachypomus (Pisces: Characidae EVALUATION OF NEW TECHNOLOGY TO MITIGATE INTRAMUSCULAR THORNS IN CACHAMA FILLETS

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    Héctor Suárez Mahecha

    2009-06-01

    Full Text Available La presencia de espinas intramusculares en filetes de cachama dificulta la comercializacion y demanda por parte de los consumidores. Hasta el momento no existen tecnologías que permitan ofrecer filetes de cachama que garanticen condiciones de seguridad frente a las espinas. El objetivo del presente trabajo fue evaluar una nueva tecnología para mitigar la presencia de espinas en filetes de cachama Piaractus brachypomus empacados al vacío y almacenados durante 30 días a 3±0,5 °C. A filetes en presentación lateral interna fueron realizados cortes profundos, paralelos y perpendiculares al eje longitudinal, a una distancia de 3 mm entre cada corte, en sentido dorso-ventral. Fueron realizados análisis microbiológico, fisicoquímico y sensorial. El análisis microbiológico muestra condiciones aceptables para el final del periodo de almacenamiento. Los valores obtenidos para este periodo, fueron de log UFC/g 7,07; 4,7 y 1100 NMP, 18 NMP para organismos psicrotrofilos, mesófilos, coliformes totales y coliformes fecales, respectivamente. No fue determinada presencia de Salmonella ni de organismos sulfito reductores. El análisis fisicoquímico mostró valores de 39,36 para BVT-N; 6,22 pH; 3,3% de pérdida de humedad 1,52; ácido tiobarbitúrico mg MA/kg. El efecto del sajado no incrementó los valores de oxidación de ácidos grasos, ni aumentó las BVT que pudiesen indicar degradación de la proteína. En el análisis sensorial los filetes sometidos a cocción fueron rechazados solamente a partir del día 25 del periodo de almacenamiento, para los atributos aroma y sabor. Durante la evaluación los panelistas no encontraron presencia de espinas, mostrando que la temperatura de cocción utilizada y los cortes en las espinas, permiten degradar la espina intramuscular evitando que sea detectada.The presence of pin bones in cachama fillets makes marketing and demand difficult by the consumers. So far, there are no technologies to provide cachama

  14. Análisis proximal, evaluación microbiológica y sensorial de carnes para hamburguesas elaboradas con cachama blanca (Piaractus brachypomus y soya (Glycine max texturizada

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    Oscar García

    2013-12-01

    Full Text Available La cachama blanca (Piaractus brachypomus es una especie económicamente importante en la acuicultura continental de América Latina y una alternativa nacional de producción de pescado para la piscicultura, la industria y el consumo. El objetivo del presente trabajo de investigación fue caracterizar mediante análisis proximal, evaluación microbiológica y sensorial, carnes para hamburguesas elaboradas con pulpa de cachama y diferentes inclusiones porcentuales de harina de soya texturizada (HST (0, 3, 6 y 9 %. Se realizó análisis proximal a las carnes crudas y cocidas, se evaluó microbiológicamente a las crudas y sensorialmente las cocidas con 100 consumidores. En las carnes para hamburguesas a mayor adición de HST favoreció la retención de agua durante la cocción y se elevó el contenido de proteína, grasa y cenizas en las carnes crudas y cocidas (p < 0,05. El análisis microbiológico reveló inocuidad alimentaria en las carnes para hamburguesas crudas, encontrándose todos los valores por debajo de lo establecido en la norma venezolana COVENIN 2127-1998 para hamburguesa y otras normas de referencia. La blandura aumentó de manera proporcional al incremento porcentual en la inclusión de HST y las formulaciones con 0, 3 y 6 % de HST se diferenciaron significativamente (p < 0,05 de la formulación con 9 %. La apariencia de las carnes de hamburguesa agradó más en las formulaciones 6 y 9 %, la blandura en 9 %, y el sabor en el control (0 %, seguido de 3 %. Algunos consumidores hicieron asociaciones de sabor a carne de pollo, mariscos y hervidos de pollo.

  15. Evaluación del tiempo de evacuación gástrica de la cachama blanca Piaractus brachypomus (Cuvier, 1818, utilizando diferentes frecuencias de alimentación y ayuno

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    José Ader Gómez-Peñaranda

    2013-12-01

    Full Text Available Este estudio estima el tiempo de vaciado del estómago de la cachama blanca (Piaractus brachypomus en el día de comienzo regular de alimentación posterior a un periodo de ayuno. Para el efecto, se recolectaron muestras de contenido estomacal en periodos de dos horas después del suministro de alimento (9:30 y 15:30 h hasta el primer indicio de vaciado. Se utilizaron cachamas con un peso de 360 ± 12 g dispuestas en cuatro tratamientos: (1 T1 = alimentación a saciedad durante 5 días y ayuno de 2 días, (2 T2 = alimentación a saciedad durante 6 días y ayuno de 1 día, (3 T3 = alimentación a saciedad durante 7 días, y (4 TC = alimentación siguiendo las tablas recomendadas por el fabricante del alimento. El análisis de datos se realizó mediante ANOVA de medidas repetidas, empleando como factores el tratamiento y el tiempo de vaciado, siendo cada repetición la unidad experimental. Las cachamas del tratamiento T1 presentaron mayor cantidad de alimento en el estómago en los muestreos posteriores al suministro de la primera y segunda ración. A diferencia del tratamiento T1, en los demás las cachamas vaciaron su contenido en el estómago en el periodo comprendido entre la primera y la segunda ración de alimentación y en el periodo posterior a la segunda ración. Por tanto, cuando el contenido estomacal fue mayor, debido a un mayor consumo de alimento en la ración, como en el caso del tratamiento (T1, el tiempo necesario para vaciar el estómago de las cachamas se incrementó.

  16. Amélioration de la gouvernance du secteur piscicole dans le bassin ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    depuis l'introduction du paiche (Arapaima gigas). La deuxième se trouvait dans le sud-est du bassin, où l'on fait l'élevage d'espèces indigènes comme le tambaqui. (Piaractus brachypomus). Premières incidences. Émergence de leaders locaux par recherche-action. L'un des principaux résultats fut de réunir les pêcheurs.

  17. Genetic identification of F1 and post-F1 serrasalmid juvenile hybrids in Brazilian aquaculture.

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    Diogo Teruo Hashimoto

    Full Text Available Juvenile fish trade monitoring is an important task on Brazilian fish farms. However, the identification of juvenile fish through morphological analysis is not feasible, particularly between interspecific hybrids and pure species individuals, making the monitoring of these individuals difficult. Hybrids can be erroneously identified as pure species in breeding facilities, which might reduce production on farms and negatively affect native populations due to escapes or stocking practices. In the present study, we used a multi-approach analysis (molecular and cytogenetic markers to identify juveniles of three serrasalmid species (Colossoma macropomum, Piaractus mesopotamicus and Piaractus brachypomus and their hybrids in different stocks purchased from three seed producers in Brazil. The main findings of this study were the detection of intergenus backcrossing between the hybrid ♀ patinga (P. mesopotamicus×P. brachypomus×♂ C. macropomum and the occurrence of one hybrid triploid individual. This atypical specimen might result from automixis, a mechanism that produces unreduced gametes in some organisms. Moreover, molecular identification indicated that hybrid individuals are traded as pure species or other types of interspecific hybrids, particularly post-F1 individuals. These results show that serrasalmid fish genomes exhibit high genetic heterogeneity, and multi-approach methods and regulators could improve the surveillance of the production and trade of fish species and their hybrids, thereby facilitating the sustainable development of fish farming.

  18. Bioacumulacion y biomagnificacion de mercurio en diferentes poblaciones de peces de la Amazonía boliviana

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    Lopez Siangas, E.I.

    2005-01-01

    La bioacumulación de mercurio respecto al tamaño, peso y edad, así como la influencia de aspectos biológicos como la alimentación, el crecimiento, la madurez sexual y el sexo, fueron determinadas en seis especies de peces piscívoros y no piscívoros de importancia regional: #Cichla monoculus# (Tucunaré), #Pygocentrus nattereri# (Piraña), #Psedoplatystoma fasciatum# (Surubí), #Plagioscion squamossisimus# (Corvina), #Colosoma macropomum# (Pacú) y #Piaractus brachypomus# (Tambaquí), en las cuenca...

  19. Optimización de un método analítico para la determinación de mercurio en muestras ambientales por espectrometría UV-Visible

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    Xiomara Piña

    2012-12-01

    Full Text Available Dithizone´s colorimetric method was modified and quasi miniaturized for mercury determination in water and Lemna minor and Piaractus brachypomus tissue. Detection limit (4-22µg.L-1 was adequate for environmental studies. Evaluation of the accuracy in water was achieved by analyzing SPEX CERTIPREP standard samples with no significant differences. 85-120% recovery percentages for digested biota were obtained. The precision was less than 10% of relative standard deviation in all the cases. The method is reliable for mercury determination in water, red-bellied and Lemna minor tissue.

  20. Optimización de un método analítico para la determinación de mercurio en muestras ambientales por espectrometría UV-Visible

    OpenAIRE

    Piña, Xiomara; Marcó Parra, Lue Merú; Poleo, Germán; Rojas, Jesús; Torres, Gosmyr

    2013-01-01

    El método colorimétrico de la ditizona fue modificado y cuasi miniaturizado para la determinación de mercurio en agua y en tejido de Lemna minor y Piaractus brachypomus. El límite de detección (4-22μg.L-1) fue satisfactorio para estudios ambientales. Para la evaluación de la exactitud en agua se analizaron patrones SPEX CERTIPREP sin diferencias significativas y para la biota digerida se obtuvieron porcentajes de recuperación en el rango de 85-120%. La precisión fue menor al 10% de desviación...

  1. ESTABILIDADE QUÍMICA E MICROBIOLÓGICA DE "MINCED FISH" DE PEIXES AMAZÔNICOS DURANTE O CONGELAMENTO

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    JESUS Rogério Souza de

    2001-01-01

    Full Text Available Foi estudada a estabilidade química e microbiológica de "minced fish" produzidos, em condições industriais, com espécies de peixes da Amazônia: aracú-comum (Schizodon fasciatus, branquinha-comum (Potamorhina latior, branquinha-de-cabeça-lisa (P. altamazonica, curimatã (Prochilodus nigricans, jaraqui-de-escama-fina (Semaprochilodus taeniurus, jaraqui-de-escama-grossa (S. insignis, mapará (Hypophthalmus edentatus, pacú-comum (Metynnis hypsauchen, pacú-manteiga (Mylossoma duriventre e pirapitinga (Piaractus brachypomum, durante 150 dias sob congelamento a -18±1°C e -36±1°C. Com base no pH, nitrogênio das bases voláteis totais (N-BVT, substâncias reagentes ao ácido tiobarbitúrico (TBARS e contagens de aeróbios mesófilos a 35°C e psicrotróficos a 7°C, e de coliformes totais e fecais (NMP, os "minced fish" obtidos a partir das espécies de peixes estudadas e de misturas de espécies (aracú+curimatã+pirapitinga; jaraqui+branquinha mantiveram-se em condições de consumo, durante o período experimental. Os resultados obtidos são altamente promissores sob o ponto de vista tecnológico.

  2. Microscopia eletrônica de varredura de parasitos branquiais de Piaractus mesopotamicus Holmberg, 1887 cultivados no Estado de São Paulo, Brasil Scanning electron microscopy of the gill parasites of cultivated Piaractus mesopotamicus Holmberg, 1887 in the State of São Paulo, Brazil

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    Maurício Laterça Martins

    2000-05-01

    Full Text Available Foram coletados 15 exemplares de Piaractus mesopotamicus (pacu, medindo em torno de 15 cm de comprimento padrão, de tanques do Centro de Aqüicultura da Unesp, Jaboticabal, SP, Brasil. Os peixes foram mantidos em aquários de 350 litros para posterior sacrifício com MS-222. Os filamentos brânquiais foram fixados em glutaraldeído a 3% para a microscopia eletrônica de varredura. Foram observados espécimes de Trichodina sp (Ciliophora, Henneguya piaractus (Myxozoa, e Anacanthorus penilabiatus (Monogenea, atacando o epitélio branquial. Neste trabalho, foram reportados a morfologia externa dos parasitos e as alterações no epitélio branquial dos peixes parasitadosFifteen specimens of Piaractus mesopotamicus (pacu, measuring 15 cm standard length, were collected from a fishpond at Aquaculture Center of Unesp, Jaboticabal, SP, Brazil. Fishes were maintained in 350 L aquariums for a further sacrifice with MS-222. For the Scanning Electron Microscopy, gill filaments were fixed in 3% glutaraldehyde. Specimens of Trichodina sp (Ciliophora, Henneguya piaractus (Myxozoa and Anacanthorus penilabiatus (Monogenea attacking on the gill epithelium were observed. In the present paper, the external morphology of parasites and the alterations in the gill epithelium of parasitized fishes were reported

  3. Trichodina colisae (Ciliophora: Trichodinidae: new parasite records for two freshwater fish species farmed in Brazil Trichodina colisae (Ciliophora: Trichodinidae: novo registro de parasito para duas espécies de peixes de água doce cultivadas no Brasil

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    Gabriela Tomas Jerônimo

    2012-12-01

    Full Text Available Family Trichodinidae comprises ciliate protozoa distributed worldwide; they are considered some of the main parasitological agents infecting cultivated fish. However, the trichodinidae parasitizing important fish species cultured in Brazil are unknown, and more taxonomic studies on this group of parasites are required. This research morphologically characterizes Trichodina colisae Asmat & Sultana, (2005 of pacu (Piaractus mesopotamicus and patinga hybrid (P. mesopotamicus × P. brachypomus cultivated in the central and southeast regions of the country. Fresh assemblies were made from mucus scraped from the skin, fins and gills, fixed with methanol and, subsequently, impregnated with silver nitrate and stained with Giemsa for assessment under light microscopy. This research reports not only the second occurrence of T. colisae in the world, but also its first occurrence in South America.Tricodinídeos são protozoários ciliados móveis com ampla distribuição mundial; são considerados um dos agentes parasitários que mais acometem peixes cultivados. No Brasil, a maioria dos tricodinídeos que parasitam importantes espécies de peixes cultivados são desconhecidos, o que requer mais estudos taxonômicos com esse grupo de parasitos. Este estudo caracteriza morfologicamente Trichodina colisae Asmat & Sultana, 2005 de pacu (Piaractus mesopotamicus e do híbrido patinga (P. mesopotamicus × P. brachypomus cultivados, respectivamente, no Centro-Oeste e Sudeste do Brasil. Foram feitas montagens a fresco do raspado de muco da pele, nadadeiras e brânquias, fixados com metanol e, posteriormente, impregnados com nitrato de prata e coradas com Giemsa para avaliação em microscopia óptica. O presente estudo relata não só a segunda ocorrência de T. colisae no mundo, mas também a primeira ocorrência na América do Sul.

  4. Fish farming of native species in Colombia: current situation and perspectives

    DEFF Research Database (Denmark)

    Cruz-Casallas, P. E.; Medina-Robles, V. M.; Velasco-Santamaria, Y. M.

    2011-01-01

    . The Colombian pisciculture is based on red Tilapia Oreochromis sp. (Linnaeus), Rainbow trout Oncorhynchus mykiss (Walbaum) and cachama blanca Piaractus brachypomus (Cuvier), which currently represent around 96% of the total national production. The remaining 4% comes from other farmed species such as bocachico......In Colombia and the rest of the world, the decrease in capture fisheries production has turned the aquaculture into an alternative source of protein for the populations food security as well as an important productive activity, generating employment and income for the rural communities...... Prochilodus magdalenae (Steindachner), carp Cyprinus carpio (Linnaeus) and yamu Brycon amazonicus (Spix & Agassiz). From the three main fish species, cachama blanca is the only native species, which has shown excellent performance in pond farming due to its rusticity, omnivorous habits, docility, meat quality...

  5. Physiological responses of fish, Piaractus mesopotamicus, to infection with the freshwater fish louse, Dolops carvalhoi. Abstract

    NARCIS (Netherlands)

    Castro, F.J.; Wendelaar Bonga, S.E.; Fernandes, N.N.

    2007-01-01

    The freshwater fish louse Dolops carvalhoi, is an ectoparasite of pacu, Piaractus mesopotamicus, that causes severe damage to its hosts. The aim of this study was to investigate the physiological responses of pacu to the stress of D. carvalhoi infection. After acclimation at the laboratory

  6. LITTER DEVOLUTION AND DECOMPOSITION IN CERRADÃO AND MATA MESOFÍTICA AREAS IN ECOLOGICAL STATION OF PIRAPITINGA – MG

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    Rômulo Guimarães Giácomo

    2012-12-01

    Full Text Available http://dx.doi.org/10.5902/198050987549This study aimed to quantify the litter and nutrients amount and to estimate the decomposition rate in areas of mesophytic forest and ‘Cerradão’ in the Ecological Station of Pirapitinga. To evaluate litter and nutrients devolution 10 conic litter traps were randomly distributed in an area 0.1 ha in each area of study, with monthly evaluations. The litter decomposition in the areas of study was evaluated by using litter bags. The total production of litter was 2.50 and 2.92 Mg ha-1 yr-1 for mesophytic forest and ‘Cerradão’ areas, respectively. The nutrients devolution importance order was nitrogen> potassium> phosphorus. The mesophytic forest showed more homogeneous distribution of litter fall over the year and higher values of total annual litter and nutrients, the highest values were observed at the dry season. The half-life decomposition of leaf litter was equivalent between areas, about 161 days in the mesophytic forest area and 173 in ‘Cerradão’ area.

  7. Antibiotic resistence of Aeromonas hydrophila isolated from Piaractus mesopotamicus (Holmberg, 1887) and Oreochromis niloticus (Linnaeus, 1758)

    OpenAIRE

    Belém-Costa,Andréa; Cyrino,José Eurico Possebon

    2006-01-01

    One of the most important problems involving treatments with antibiotics against Aeromonas hydrophila isolated from fishes is that antibiotic resistance develops readily. The antimicrobial activity of chemotherapeutants in isolates from pacu Piaractus mesopotamicus (Holmberg, 1887) and tilapia Oreochromis niloticus (Linnaeus, 1758) was tested by the Kirby-Bauer disk method, over Mueller-Hinton surface agar previously inoculated with 100 µL of bacterial suspensions. After regular incubation, i...

  8. Plasma testosterone and 11-ketotestosterone levels of male pacu Piaractus mesopotamicus (Cypriniformes, Characidae

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    R. Gazola

    1997-12-01

    Full Text Available The levels of testosterone (T and 11-ketotestosterone (11-KT of the South American pacu Piaractus mesopotamicus were determined by radioimmunoassay during two stages of the reproductive cycle, i.e., resting and maturation, and the gonadosomatic index (GSI was calculated. The highest levels of T and 11-KT were reached during the maturation stage (T = 2400 ± 56 pg/ml; 11-KT = 2300 ± 60 pg/ml and lower levels were maintained during the resting period. The rise in androgen levels occurred with the appearance of spermatozoa in the maturation stage, when GSI was highest

  9. Hematologia e sinais clínicos de Piaractus mesopotamicus infectados experimentalmente com Aeromonas hydrophila = Hematology and clinical signs of Piaractus mesopotamicus experimentally infected with Aeromonas hydrophila

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    Flávio Ruas Moraes

    2009-01-01

    Full Text Available Este ensaio teve como objetivo avaliar as respostas hematológicas e a ocorrência de sinais clínico-patológicos de Piaractus mesopotamicus infectados experimentalmente por Aeromonas hydrophila. Foram utilizados 324 pacus, P. mesopotamicus, com peso de 102,84 ±27,1 g, distribuídos em 27 caixas de 300 L de capacidade, sendo 14 peixes por caixa. Os peixes foram mantidos nas caixas durante um mês, recebendo dieta balanceada, período em que se evitou qualquer tipo de manejo estressante. Passado esse período, foram infectadoscom 6 x 106 UFC de A. hydrophila, injetada via intraperitoneal. As coletas e análises de sangue foram realizadas 24h antes da infecção experimental e 24h após a infecção. Os resultados permitem concluir que a infecção por A. hydrophila em P. mesopotamicus écaracterizada por escurecimento da derme e sinais clínicos-patológicos relacionados à hemorragia, anemia normocítica-hipocrômica, redução nos níveis de proteínas, globulinasplasmáticas e eosinófilos, leucopenia, linfopenia, trombocitopenia, neutrofilia e monocitose. The purpose of this study was to evaluate the hematological response and clinical sign of Piaractus mesopotamicus infected byAeromonas hydrophila. Were used 324 pacus, P. mesopotamicus weighing 102.84 ± 27.1 g distributed in 27 water tanks with 300 L of capacity, 14 fish per tank. The fish were kept in the water tanks during one month, receiving appropriate diet. In this period was avoidedstressing management. After this period, the fish were infected with 6 × 108 cfu of A. hydrophila fish-1, injected intraperitoneally. The blood collection was carried 24h before experimental infection and 24h after its. The A. hydrophila infection in P. mesopotamicus ischaracterized by dark skin and clinical signs related to hemorrhage, hypochromic normocytic anemia, decrease on plasmatic proteins and globulins levels, leucopenia, lymphopenia, thrombocytopenia, eosinophilia, neutrophilia and monocytosis.

  10. Processed soybean in diets for pacu (Piaractus mesopotamicus

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    Marcia Regina Stech

    2015-02-01

    Full Text Available Changes in development and in physiological parameters of fingerlings of the pacu (Piaractus mesopotamicus fed on diets with high levels of integral crude, extruded, toasted soybean and soybean meal were assessed. The products were evaluated in practical diets for pacu, initially weighing 70 ± 2.19 g, during 82 days. Nine treatments were studied in a 2 × 4 + 1 factorial scheme which corresponded to two fish meal protein replacement levels (50 and 100% and four soybean products, plus control (100% of fish meal - FM. Development, organosomatic indexes and physiological parameters were evaluated. No differences were reported with regard to weight gain, food intake, food conversion, protein efficiency ratio and specific growth rate. A significant interaction was registered for plasma protein between the evaluated ingredients and replacement percentage of fish meal protein. Results showed that the ingredients assessed did not affect the development of the pacu when compared to fish fed on control diet. Protein retention was favored when toasted soybean and when 50% of the diet’s protein fraction from fish meal were employed.

  11. APORTE E DECOMPOSIÇÃO DE SERAPILHEIRA EM ÁREAS DE CERRADÃO E MATA MESOFÍTICA NA ESTAÇÃO ECOLÓGICA DE PIRAPITINGA - MG

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    Rômulo Guimarães Giácomo

    2012-01-01

    Full Text Available This study aimed to quantify the litter and nutrients amount and to estimate the decomposition rate in areas of mesophytic forest and 'Cerradão' in the Ecological Station of Pirapitinga. To evaluate litter and nutrients devolution 10 conic litter traps were randomly distributed in an area 0.1 ha in each area of study, with monthly evaluations. The litter decomposition in the areas of study was evaluated by using litter bags. The total production of litter was 2.50 and 2.92 Mg ha-1 yr-1 for mesophytic forest and 'Cerradão' areas, respectively. The nutrients devolution importance order was nitrogen> potassium> phosphorus. The mesophytic forest showed more homogeneous distribution of litter fall over the year and higher values of total annual litter and nutrients, the highest values were observed at the dry season. The half-life decomposition of leaf litter was equivalent between areas, about 161 days in the mesophytic forest area and 173 in 'Cerradão' area.

  12. Parasitism by Monogenoidea in Piaractus mesopotamicus (Characiformes, Characidae cultivated in Paraná River (Brazil

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    M. S. L. Leão

    2017-05-01

    Full Text Available Abstract This study investigated the occurrence, prevalence, mean abundance and mean intensity of monogenoidean parasites in Piaractus mesopotamicus farmed in cages in the reservoir of the Itaipu Hydroelectric Power Station, Paraná River, Brazil. The parasite distribution pattern and the correlation of prevalence and abundance with the total length of hosts were also investigated. Four monogenoidean species were collected: Anacanthorus penilabiatus, A. toledoensis, Mymarothecium ianwhitingtoni and M. viatorum. All the parasites collected in P. mesopotamicus showed the typical aggregated distribution pattern, and the abundance and the prevalence did not shown any correlation with the total length of hosts.

  13. Desenvolvimento e diferenciação dos ovócitos de pacu, Piaractus mesopotamicus (Holmberg, 1887 (Osteichthyes, Characidae Oocyte development and differentiation in pacu, Piaractus mesopotamicus (Holmberg, 1887 (Osteichthyes, Characidae

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    Massuka Yamane Narahara

    2002-05-01

    Full Text Available O objetivo deste trabalho foi o de esclarecer dúvidas referentes ao desenvolvimento e à diferenciação dos ovócitos de Piaractus mesopotamicus (Osteichthyes, Characidae, ultra-estruturalmente, acompanhando as transformações que ocorreram durante o processo de ovogênese tais como: formação e acúmulo de várias organelas, inclusões nucleares e/ou citoplasmáticas e a camada ou envelope folicular. Na fase de crescimento primário são evidentes os corpúsculos de Balbiani, mas não são claros seus papéis. Estão presentes, também, as peculiares estruturas lamelares. A segunda fase, a de crescimento secundário, caracteriza-se, inicialmente, pela formação de alvéolos corticais. A seguir, os grânulos de vitelo protéico formam-se na região periférica com abundância de mitocôndrias e ribossomos. Mudanças no epitélio folicular (granulosa são descritas concomitantemente com a formação da zona radiata, que constitui o envoltório folicular (envelope.This work aim is to clarify doubts about the Piaractus mesopotamicus (Osteichthyes, Characidae oocyte ultrastructural development and differentiation, following the transformations during the ovogenic processes, such as formation and accumulation of various organelles, nucleolar and/or citoplasmic inclusions, and follicular wall (envelope. During the primary growth phase, Balbiani corpuscles are evident, but their role is not clear. The peculiar lamellae structures are also present. The second phase (secondary growth is initially characterized by cortical alveolus formation. After that, protein yolk granules appear in the peripherical regions, where mitochondria and ribosomes are abundant. Changes in the follicle epitelium (granulosa are described together with the radiate zone formation, which constitutes the follicular envelope.

  14. Occurrence and ultrastructural characterization of "nuage" during oogenesis and early spermatogenesis of Piaractus mesopotamicus Holmberg, 1887 (Teleostei

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    F. C. Abdalla

    Full Text Available We investigated the occurrence and ultrastructurally characterized electrondense nuclear material (nuage released from the nucleus during oogenesis and early spermatogenesis of Piaractus mesopotamicus, a fish from Pantanal Matogrossense (Brazil having a seasonal reproductive cycle. The female germ cells presented two instances of nuclear material extrusion: in the oogonia and in the oocyte in the perinucleolar phase. In males, material with similar morphology and behavior occurred in the spematogonia. In all cases, this material was associated to mitochondria. The possible function of this material is discussed.

  15. Paraoxonase activity in liver of Pacu, Piaractus mesopotamicus Holmberg (Characidae

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    Vera Lucia F. Cunha Bastos

    1998-01-01

    Full Text Available Enzymatic production of p-nitrophenol in liver of Piaractus mesopotamicus Holmberg, 1887 was consistently assayed at pH 8.5 using 7.5 mM paraoxon as substrate. This pacu liver paraoxonase activity was activated by NaCl. Apparent values of K M were 2.42 x 10-3 M in the presence of 0.5 M NaCl and 8.99 x 10-3 M without NaCl. Apparent maximum velocity values calculated in the absence and presence of 0.5 M NaCl were 1.09 x 10-3 µmoles/min/mg of proteins and 1.29 x 100-3 µmoles/min/mg of proteins, respectively. These Vmax values are fifty-fold the value described for trout (Salmo trutta Linnaeus, 1758 liver paraoxonase. Paraoxonase activity of pacu liver homogenates was recovered as much in cytosolic as in particulate cellular subtractions, but the particulate subtractions showed higher specific activities. The data presented here indicate that hepatic hydrolysis of organophosphorous pesticides may not be an important detoxification process in pacu.

  16. Tecnologia do pescado de água doce: aproveitamento do pacu (Piaractus mesopotamicus Freshwater fish technology: utilization of "pacu"(Piaractus mesopotamicus

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    E.R. Szenttamásy

    1993-09-01

    Full Text Available Para o estudo da viabilidade do Pacu (Piaractus mesopotamicus para processamento tecnológico, foram testados os processos de defumação, salga e secagem e enlatamento. Analisou-se também a farinha dos resíduos. Utilizou-se peixes provenientes de tanques de piscicultura do município de Piracicaba-SP e o produto final foi avaliado para o consumo na merenda escolar municipal. Foram feitas análises quanto aos teores de lipídeos, umidade, proteína e cinza. Os produtos processados por salga, defumação e enlatamento foram analisados também quanto ao teor de sal (NaCl; os defumados e enlatados foram submetidos a análise sensorial com avaliação de aparência, cor, aroma, sabor e textura. O pacu "in natura", defumado, salgado seco e enlatado apresentou, em porcentagem, respectivamente, 18,99; 23,80; 52,53; 18,59 de proteína, 3,79; 2,69; 18,31; 14,34 de lipídeos e 1,82; 3,13; 17,76; 2,79 de cinza. Para o pacu enlatado 56% e 33% dos degustadores o classificaram como um produto de excelente e bom sabor. O pacu defumado foi classificado como de excelente sabor por 25% dos provadores e de bom sabor por 55%.

  17. Leukocytes respiratory burst and lysozyme level in pacu (Piaractus mesopotamicus Holmberg, 1887

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    JS. Abreu

    Full Text Available Innate immune responses are useful to determine the health status of fish and to evaluate the effect of immunomodulatory substances in fish farming. Leukocytes respiratory burst was measured in pacu (Piaractus mesopotamicus using chemiluminescence assay and nitroblue tetrazolium (NBT reduction assay. The nitroblue tetrazolium reduction seemed more adequate than chemiluminescence assay for leukocytes oxidative burst determination, since it was difficult to isolate the blood leucocytes for chemiluminescence assay. Plasma and serum lysozyme were measured using a turbidimetric assay. The heating of serum and plasma samples (56 ºC for 30 minutes for complement system inactivation darkened the plasma samples and interfered in the results. The lysozyme activity in serum was higher than in plasma, suggesting that serum samples are more appropriate for the analysis. This study established protocols that can be useful tools in the study of immune mechanisms of the tropical fish pacu.

  18. Evaluation of the haematological parameters in Piaractus mesopotamicus Holmberg (Osteichthyes, Characidae with Argulus sp. (Crustacea, Branchiura infestation and treatment with organophosphate

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    Marcos Tavares-Dias

    1999-06-01

    Full Text Available Haematological parameters as erythrocytes, leukocytes and plasma glucose in Piaractus mesopotamicus Holmberg, 1887 were analyzed. Fish were parasitized with Argulus sp. (Crustacea, Branchiura and treated with 0.4 mg of thriclorphon 500/L water. The effects of parasitism and the action of the treatment were evaluated. Parasitized fish showed greater number of monocytes (P>0.05 and special granulocitic cells (P0.05. Organophosphate treatment presented significantly reduction (P>0.05 in red blood cells (RBC and hemoglobin.

  19. Serum bactericidal activity as indicator of innate immunity in pacu Piaractus mesopotamicus (Holmberg, 1887

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    J.D. Biller-Takahashi

    2013-12-01

    Full Text Available The immune system of teleost fish has mechanisms responsible for the defense against bacteria through protective proteins in several tissues. The protein action can be evaluated by serum bactericidal activity and this is an important tool to analyze the immune system. Pacu, Piaractus mesopotamicus, is one of the most important fish in national aquaculture. However there is a lack of studies on its immune responses. In order to standardize and assess the accuracy of the serum bactericidal activity assay, fish were briefly challenged with Aeromonas hydrophila and sampled one week after the challenge. The bacterial infection increased the concentration of protective proteins, resulting in a decrease of colony-forming unit values expressed as well as an enhanced serum bactericidal activity. The protocol showed a reliable assay, appropriate to determine the serum bactericidal activity of pacu in the present experimental conditions.

  20. Haematological characteristics of Brazilian Teleosts: III. Parameters of the hybrid tambacu (Piaractus mesopotamicus Holmberg x Colossoma macropomum Cuvier (Osteichthyes, Characidae

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    Marcos Tavares-Dias

    2000-12-01

    Full Text Available Fifty six specimens of the hybrid "tambacu" (Piaractus mesopotamicus Holmberg, 1887 male x Colossoma macropomum Cuvier, 1818 female were collected from fishfarm of Guariba, São Paulo, to evaluate their haematology. Fishes presented 400.0 to 3,100.0 g total weight and 20.0 to 52.0 cm total length. Haemoglobin, haematocrit, mean corpuscular haemoglobin content (MCHC and percentage of defense blood cells including leucocytes and thrombocytes, were studied. Statistical analysis showed positive correlation (P<0.01 between haematocrit, MCHC and haemoglobin rate. Nevertheless, thrombocytes and lymphocytes showed negative correlation (P<0.01.

  1. Inflamación crónica granulomatosa en el pez teleósteo Piaractus mesopotamicus: modelo de estudio histopatológico

    OpenAIRE

    G Manrique, Wilson; AP Figueiredo, Mayra; Belo, Marco AA; Martins, Maurício L; Moraes, Flávio R

    2017-01-01

    Objetivo. Este estudio evaluó la cinética celular y la formación de granuloma durante la inflamación crónica inducida por el Bacilo Calmette-Guérin (BCG) en el músculo esquelético de Piaractus mesopotamicus, como modelo histopatológico para estudiar la inmunidad innata. Materiales y métodos. Sesenta peces fueron divididos en dos grupos: peces inoculados con BCG y no inoculados y la respuesta inflamatoria analizada en 3, 7, 14, 21 y 33 días post-inóculo (DPI) por medio del análisis histopatoló...

  2. Biological indicators of stress in pacu (Piaractus mesopotamicus after capture

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    JS. Abreu

    Full Text Available The effects of capture (chasing, netting and air exposure on cortisol, glucose, chloride, sodium, potassium and calcium concentrations, osmolality, hematocrit, hemoglobin concentration, red blood cells count (RBC and mean corpuscular volume (MCV were investigated in pacu (Piaractus mesopotamicus. A total of 132 fish (49.7 ± 11.7 g were subjected to capture and 3 minutes air exposure and capture and 5 minutes air exposure. Nine fish at each treatment were sampled at 5, 15, 30, 60 minutes and 24 hours after the procedure. Nine undisturbed fish were sacrificed before the handling and used as controls. Capture resulted in a rise in blood cortisol and glucose 30 and 5 minutes, respectively, after both air exposures. Both indicators returned to resting levels 24 hours after capture. In both fish groups, plasma chloride decreased 60 minutes after capture, not recovering the resting levels within 24 hours after, and serum sodium rose at 15 and 30 minutes and recovered the resting levels 24 hours later. There were no significant changes neither in potassium, calcium and osmolality nor in hematocrit, hemoglobin, RBC and MCV as a consequence of capture. The sequential stressors imposed to pacu during capture activated the brain-pituitary-interrenal axis (cortisol and glucose responses but the activation of the brain-sympathetic-chromaffin cell axis was apparently moderate (ionic and hematological responses.

  3. Efeito de três diferentes fontes de extrato de pituitárias na indução gonadal em machos e fêmeas de pacu (Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v27i4.1146 Effects of three different sources of pituitary extract on gonadal inducer in male and female pacu (Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v27i4.1146

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    Jayme Aparecido Povh

    2005-03-01

    Full Text Available Machos e fêmeas de (Piaractus mesopotamicus foram induzidas com extrato de hipófise de frango de corte (BCPE, coelho (RPE e de carpa (CPE. Os parâmetros vigor espermático, motilidade progressiva, taxa de fertilização e eclosão de acordo com a origem do sêmen, não apresentou diferença (p > 0,05 entre os tratamentos. O tratamento com BCPE produziu o menor volume de sêmen (p 0,05 para o taxa de espermatozóides com anormalidades nos tratamentos, mas as patologias secundárias foram elevadas (p P. mesopotamicusMale and female pacus (Piaractus mesopotamicus were induced with broiler chicken (BCPE, rabbit (RPE, and carp (CPE pituitary extracts. The parameters for spermatic vigor, progressive motility, fertilization and hatching rate, according to semen origin, did not show any differences among the treatments (p > 0.05. RPE produced the lowest (p 0.05 in the total rate of abnormal spermatozoa among the treatments, but the secondary pathologies were higher (p 0.05 between BCPE and CPE were found for accumulated thermal unit, number of oocytes/spawning grams, fertilization and hatchery rates according to treatment origin. The result indicates that BCPE use is recommended for gonadal induction of P. mesopotamicus

  4. Alimentação e comportamento de larvas de pacu, Piaractus mesopotamicus (Holmberg, 1887 Feeding and behavior of pacu, Piaractus mesopotamicus (Holmberg, 1887 larvae

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    Eduardo Lopes Beerli

    2004-02-01

    Full Text Available Conduziu-se este trabalho com o objetivo de avaliar o efeito da utilização de dietas naturais e artificiais sobre o desempenho e comportamento de larvas de pacu (Piaractus mesopotamicus, entre o 2º e o 10º dia de vida. Foram utilizadas 30 caixas plásticas, cada uma com 30 litros de água e renovação contínua, onde as larvas foram mantidas durante o período experimental. Cada caixa recebeu 10 larvas por litro, totalizando 300 larvas/caixa. Foram testados 6 tratamentos, cada qual com 5 repetições. Os tratamentos foram: T1-ração, T2-plâncton, T3-artêmia, T4-plâncton + ração, T5-artêmia + ração e T6-artêmia + plâncton. As larvas foram alimentadas 6 vezes ao dia, nos horários de 4, 8, 12, 16, 20 e 24 horas. A temperatura da água foi mantida constante a 27ºC, o oxigênio dissolvido permaneceu na faixa de 6,16 ± 0,34 e o pH, entre 7,16 ± 0,22. Aos 2, 4, 6, 8 e 10 dias de vida, foram coletadas amostras de 30 larvas para determinação do comprimento total e peso. No final do experimento (10º dia, as larvas que receberam artêmia + plâncton (T6 alcançaram os maiores valores de comprimento total (8,35 mm e peso corporal (3518 µg, em relação a todas as outras dietas testadas. As larvas devem permanecer em laboratório por um período de 6 dias após a eclosão, recebendo alimento do terceiro ao sexto dia. A partir do sexto dia, as larvas estão com a vesícula gasosa completamente inflada e apresentam nado contínuo.The objective of this research was to evaluate the effect of natural and artificial diets on the development and behavior of pacu (Piaractus mesopotamicus larvae, between the 2nd and 10th day post hatch. The larvaes were kept in 30L - plastic boxes (n = 30 boxes, in constant flow-through. The larvae density was 10 post-larvae/L (300 larvae/box. Six diets with 4 sampling days (4, 6, 8 and 10 days post-hatch, n = 30 larvae using 5 repetitions were tested. The diets were: T1- commercial feed, T2- plancton, T3

  5. Molecular cloning and sequence analysis of growth hormone cDNA of Neotropical freshwater fish Pacu (Piaractus mesopotamicus

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    Janeth Silva Pinheiro

    2008-01-01

    Full Text Available RT-PCR was used for amplifying Piaractus mesopotamicus growth hormone (GH cDNA obtained from mRNA extracted from pituitary cells. The amplified fragment was cloned and the complete cDNA sequence was determined. The cloned cDNA encompassed a sequence of 543 nucleotides that encoded a polypeptide of 178 amino acids corresponding to mature P. mesopotamicus GH. Comparison with other GH sequences showed a gap of 10 amino acids localized in the N terminus of the putative polypeptide of P. mesopotamicus. This same gap was also observed in other members of the family. Neighbor-joining tree analysis with GH sequences from fishes belonging to different taxonomic groups placed the P. mesopotamicus GH within the Otophysi group. To our knowledge, this is the first GH sequence of a Neotropical characiform fish deposited in GenBank.

  6. Paraoxonase activity in sera from Piaractus mesopotamicus Holmberg (Characidae and Hypostomus punctatus Valenciennes (Siluridae

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    Vera Lucia F. Cunha Bastos

    1998-01-01

    Full Text Available A paraoxonase activity present in serum of two Brazilian fish species was consistently assayed at pH 8.5 using 7.5 mM paraoxon final concentration. The paraoxonase activity was more activated by 0.5 M NaCl in serum of Piaractus mesopotanricus Holmberg, 1887 (pacu than in serum of Hypostomus punctatus Valenciennes, 1840 (cascudo. Apparent values of K M were 3.3 x 10-3 M for cascudo and pacu paraoxonase activity in the presence of 0.5 M NaCl. Apparent maximum velocity values calculated in the presence of 0.5 M NaCl were 6.1 and 6.5 nmole/min/mL of serum for cascudo and pacu, respectively. Vmax/K M ratio values of determinations in the presence and absence of 0.5 M NaCl showed that NaCl had a more evident effect on increasing the affinity of serum paraoxonase for paraoxon in pacu serum. Young specimens of pacu showed a marked decreased paraoxonase serum activity when kept in tanks treated with 0.25 ppm methyl-parathion.

  7. Na2EDTA anticoagulant impaired blood samples from the teleost Piaractus mesopotamicus

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    Thaís Heloisa Vaz Farias

    2016-05-01

    Full Text Available Abstract: The present study aimed to evaluate the effects of Na heparin and Na2EDTA on blood of Piaractus mesopotamicus (360.7±42.4g, 26.4±1.0cm. Twenty fishes were sampled in two experiment trials, ten for erythrocyte fragility analysis and ten for hematologic and plasma biochemical study. The blood collected by venous-caudal puncture was fractioned and stored in anticoagulants solution: Na2EDTA 10%, Na2EDTA 3%, Na heparin 5000 IU and Na heparin 100 IU. Plasmatic levels of calcium presented in the Na2EDTA stored samples were about 80% lower than both heparin groups. Blood samples of P. mesopotamicus stored with Na2EDTA demonstrated increase in the hematocrit and MCV, and decrease in MCHC. The dose-response effect was observed in this study. The results are reinforced by the higher levels of plasmatic protein and hemolysis presented in the Na2EDTA 10% stored blood, confirming the deleterious effect of this anticoagulant treatment on the quality of blood samples. Na2EDTA is not indicated to store P. mesopotamicus blood samples, but sodium heparin at 100 IU is the most recommended anticoagulant, since this treatment presented the lower rate of alterations in the stored blood.

  8. Water temperature, body mass and fasting heat production of pacu (Piaractus mesopotamicus).

    Science.gov (United States)

    Aguilar, Fredy A A; Cruz, Thaline M P DA; Mourão, Gerson B; Cyrino, José Eurico P

    2017-01-01

    Knowledge on fasting heat production (HEf) of fish is key to develop bioenergetics models thus improving feeding management of farmed species. The core of knowledge on HEf of farmed, neotropical fish is scarce. This study assessed the effect of body mass and water temperature on standard metabolism and fasting heat production of pacu, Piaractus mesopotamicus, an omnivore, Neotropical fresh water characin important for farming and fisheries industries all through South American continent. An automated, intermittent flow respirometry system was used to measure standard metabolic rate (SMR) of pacu (17 - 1,050 g) at five water temperatures: 19, 23, 26, 29 and 33 °C. Mass specific SMR increased with increasing water temperature but decreased as function of body mass. The allometric exponent for scaling HEf was 0.788, and lied in the range recorded for all studied warm-water fish. The recorded van't Hoff factor (Q10) for pacu (2.06) shows the species low response to temperature increases. The model HEf = 0.04643×W0.7882×T1.837 allows to predict HEf (kJ d-1) from body mass (W, kg) and water temperature (T, °C), and can be used in bioenergetical models for the species.

  9. Water temperature, body mass and fasting heat production of pacu (Piaractus mesopotamicus

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    FREDY A.A. AGUILAR

    Full Text Available ABSTRACT Knowledge on fasting heat production (HEf of fish is key to develop bioenergetics models thus improving feeding management of farmed species. The core of knowledge on HEf of farmed, neotropical fish is scarce. This study assessed the effect of body mass and water temperature on standard metabolism and fasting heat production of pacu, Piaractus mesopotamicus, an omnivore, Neotropical fresh water characin important for farming and fisheries industries all through South American continent. An automated, intermittent flow respirometry system was used to measure standard metabolic rate (SMR of pacu (17 - 1,050 g at five water temperatures: 19, 23, 26, 29 and 33 °C. Mass specific SMR increased with increasing water temperature but decreased as function of body mass. The allometric exponent for scaling HEf was 0.788, and lied in the range recorded for all studied warm-water fish. The recorded van't Hoff factor (Q10 for pacu (2.06 shows the species low response to temperature increases. The model HEf = 0.04643×W0.7882×T1.837 allows to predict HEf (kJ d-1 from body mass (W, kg and water temperature (T, °C, and can be used in bioenergetical models for the species.

  10. Microsatellite analysis of the parental contribution of Piaractus mesopotamicus to the production of offspring in the semi-natural system of reproduction

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    Jayme Aparecido Povh

    2010-04-01

    Full Text Available The objective of this study was to evaluate the genetic diversity and the parental contribution of Piaractus mesopotamicus in the production of offspring in the semi-natural system of reproduction. Twenty parental fishes (eleven males and nine females and the total of 100 larvae were evaluated by microsatellite marker. The parents and offspring had thirty-one alleles and heterozygosity of 0.550 and 0.563, respectively. The females were fertilised by two up to six males while the males fertilised three up to five females. The contribution of the females and males to the offspring were 66.6 and 58%, respectively. Such results indicated no loss in the genetic variability in the offspring, and the parents had multiple paternity and reasonable contribution to the offspring production.O objetivo deste trabalho foi avaliar a diversidade genética e a contribuição parental de Piaractus mesopotamicus na produção de descendência no sistema seminatural de reprodução. Vinte peixes parentais (onze machos e nove fêmeas e o total de 100 larvas foram avaliados por meio do marcador microssátelite. Os parentais e a progênie tiveram trinta e um alelos e heterozigosidade de 0,550 e 0,563, respectivamente. As fêmeas foram fertilizadas por dois até seis machos enquanto machos fertilizaram três até cinco fêmeas. A contribuição de fêmeas e machos para a descendência seja 66,6 e 58,0%, respectivamente. Tais resultados não indicam diminuição da variabilidade genética na progênie e os parentais apresentaram paternidade múltipla e razoável contribuição à produção de descendência.

  11. BIOCHEMICAL PARAMETERS FOR Piaractus mesopotamicus, Colossoma macropomum (Characidae AND HYBRID TAMBACU (P. mesopotamicus X C. macropomum

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    Marcos Tavares-Dias

    2010-06-01

    Full Text Available A study for investigating the values of plasma glucose,serum total protein and serum ions (calcium, potassium, magnesium,sodium and chloride was carried out in young Colossomomamacropomum Cuvier, 1818, Piaractus mesopotamicus Holmberg,1887 and the hybrid tambacu (P. mesopotamicus x C. macropomum,kept in intensive system. Glucose concentrations were higher intambacu than in P. mesopotamicus and C. macropomum. Totalprotein levels were higher in P. mesopotamicus than both C.macropomum and tambacu. C. macropomum presented higherconcentrations of sodium and chloride, while P. mesopotamicushad higher concentrations of potassium and magnesium.However, levels of calcium were similar for the species studied.The hybrid tambacu showed the smallest levels of total protein,and intermediate levels of sodium, potassium, magnesium andchloride, compared to both P. mesopotamicus and C. macropomum.Baseline values for healthy fish in aquaculture were established,and they may be used for further comparisons in studies with wildpopulations of P. mesopotamicus and C. macropomum.

  12. Estudo do potencial do pacu (Piaractus mesopotamicus como agente de controle biológico de Egeria densa, E. najas e Ceratophyllum demersum Evaluation of the biocontrol potential of pacu (Piaractus mesopotamicus for Egeria densa, E. najas and Ceratophyllum demersum

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    D.M.Y. Miyazaki

    2003-01-01

    Full Text Available Visando fornecer subsídios para elaboração de sistema de manejo integrado das grandes massas de plantas daninhas aquáticas submersas em lagos e represas, o presente trabalho teve como objetivo verificar a eficiência do pacu (Piaractus mesopotamicus como agente de controle biológico de Egeria densa, E. najas e Ceratophyllum demersum. As espécies de plantas daninhas foram oferecidas individualmente, duas a duas e as três espécies juntas. Verificou-se que este peixe tem uma eficiência média de controle dessas plantas daninhas variando entre 28 e 100%, podendo eliminar uma massa verde dessas plantas, com a mesma quantidade de seu peso, em sete dias. A eficiência de controle diária aumentou com o tempo de predação. O pacu é mais seletivo para E. densa ou E. najas quando na presença de C. demersum. Não ocorreu alteração na eficiência de controle do pacu sobre E. densa ou E. najas em todos os tratamentos e nos três períodos estudados (três, cinco e sete dias.In order to provide basic information for the establishment of integrated management systems for submersed aquatic weeds in lakes and reservoirs, this research evaluated the efficiency of pacu (Piaractus mesopotamicus as a biocontrol agent of Egeria densa, E. najas and Ceratophyllum demersum. One, two and the three plant species together were offered to the fish. The average efficacy of this fish to control these plants ranged between 28 and 100%. The fish could eliminate a fresh mass of these plants, equivalent to its body weight, in seven days of predation period. Control efficiency increased with increasing duration of the trials. Pacu is more selective in controlling E. densa or E. najas when in the presence of C. demersum. No decreased efficacy was observed in the control of E. densa or E. najas in any of the treatments nor in any of three time periods studied (3, 5, and 7 days.

  13. Antibiotic resistence of Aeromonas hydrophila isolated from Piaractus mesopotamicus (Holmberg, 1887 and Oreochromis niloticus (Linnaeus, 1758 Resistência de Aeromonas hydrophila isolada de Piaractus mesopotamicus (Holmberg, 1887 e Oreochromis niloticus (Linnaeus, 1758 a antibióticos

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    Andréa Belém-Costa

    2006-06-01

    Full Text Available One of the most important problems involving treatments with antibiotics against Aeromonas hydrophila isolated from fishes is that antibiotic resistance develops readily. The antimicrobial activity of chemotherapeutants in isolates from pacu Piaractus mesopotamicus (Holmberg, 1887 and tilapia Oreochromis niloticus (Linnaeus, 1758 was tested by the Kirby-Bauer disk method, over Mueller-Hinton surface agar previously inoculated with 100 µL of bacterial suspensions. After regular incubation, isolates from tilapia and pacu were uniformly resistant to amoxicillin, ampicillin, lincomycin, novobiocin, oxacillin, penicillin, and trimetoprim+sulfametoxazole. The A. hydrophila type strain presented resistance to the same antimicrobial substances and also against rifampicin; the bacterial isolate from pacu were the only strain resistant to tetracyclin. Isolates from both pacu and tilapia had intermediate reaction with erytromycin. The use of drugs in commercial fish farms in Brazil can favor the development of resistant bacterial strains in native fish species as already observed for exotic species, commercially produced for longer time.Um dos maiores problemas envolvendo o tratamento com antibióticos contra Aeromonas hydrophila isolada de peixes confinados é a rápida resistência ao antibiótico desenvolvida pela bactéria. A atividade antimicrobiana de quimioterapêuticos em isolados a partir de pacu Piaractus mesopotamicus (Holmberg, 1887 e tilápia Oreochromis niloticus (Linnaeus, 1758 foi verificada pelo método de difusão de antibiótico em discos de Kirby-Bauer, sobre uma superfície de Agar Mueller-Hinton previamente inoculada com 100 µL de suspensão bacteriana. Após o período de incubação, os isolados de tilápia e pacu foram uniformemente resistentes a amoxicilina, ampicilina, lincomicina, novobiocina, oxacilina, penicilina e trimetoprim+sulfametoxazol. A cepa tipo para A. hydrophila apresentou resistência às mesmas subst

  14. Efeito da granulometria do milho no desempenho de juvenis de pacu, Piaractus mesopotamicus (Holmberg, 1887

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    M.F Polese

    2010-12-01

    Full Text Available Avaliou-se o efeito de diferentes granulometrias do milho da ração no desempenho de juvenis de pacu, Piaractus mesopotamicus. Foram utilizados 120 juvenis com peso inicial de 8,42±0,89, comprimento total de 7,03±0,20cm, comprimento padrão de 6,32±0,13cm e altura de 3,21±0,11cm, distribuídos em 20 aquários (300L, na densidade de seis peixes por unidade experimental (aquário, em delineamento inteiramente ao acaso, com cinco tratamentos constituídos por diferentes granulometrias - 850, 710, 500, 300, 150µm - do milho na composição da ração. Cada tratamento tinha quatro repetições. O tratamento que proporcionou melhor desempenho dos animais foi o com granulometria do milho de 150µm, destacando-se a conversão alimentar de 1,38, enquanto no tratamento com maior granulometria a conversão alimentar foi de 1,61. Assim, recomenda-se usar a granulometria de 150µm.

  15. Parâmetros sangüíneos de pacu Piaractus mesopotamicus (Holmberg, 1887 alimentados com dietas suplementadas com cromo trivalente em duas densidades de estocagem = Hematological parameters of pacu Piaractus mesopotamicus (Holmberg, 1887 fed diets supplemented with trivalent chromium in two stocking densities

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    Rodrigo Yudi Fujimoto

    2007-10-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da suplementação com cromo trivalente (0, 6, 12 e 18 mg kg-1 de ração sobre as variáveis hematológicas de Piaractus mesopotamicus, mantidos em duas densidades de estocagem (4 e 20 kg m-3. Os mantidos na maior densidade e alimentados com dietas suplementadas com 0 e 6 mg de cromo kg-1apresentaram redução do número de linfócitos circulantes, sugerindo má adaptação a essa condição de alta densidade. Nas dietas suplementadas com 12 e 18 mg kg-1, tal efeito não foi observado, porém verificou-se aumento do número de trombócitos no tratamento com 12 mg de cromo kg-1. A inexistência de diferença significativa entre os tratamentos, aos 30 dias, sugere a adaptação dos peixes ao tipo de alimento e à situação de alta densidade. Portanto, nas condições deste ensaio, a suplementação com 12 e 18 mg de cromo kg-1 é interessante como estratégia alimentar durante 15 dias.This work evaluated the effects of chromium supplementation on thehematological parameters of Piaractus mesopotamicus Holmberg, 1887 maintained in two stocking densities. Fish were fed diets supplemented with 0, 6, 12 and 18 mg trivalent chromium kg-1 dry ration and maintained at 4 and 20 kg m-3. The fish under high stockingdensity and fed diets supplemented with 0 and 6 mg kg-1 showed reduction in the number lymphocytes, which suggests non-adaptation to this condition of high density. This was not observed in fish fed diets supplemented with 12 and 18 mg chromium kg-1, but an increasein the number of thrombocytes was evident. The lack of difference between treatments after 30 days may suggest a possible adaptation of fish to the situation. It can be added that supplementation with 12 and 18 mg chromium kg-1 is an interesting feeding strategy for aperiod of 15 days.

  16. Histologia da pele do pacu (Piaractus mesopotamicus e testes de resistência do couro - DOI: 10.4025/actascianimsci.v25i1.2071 Histology of skin of Piaractus mesopotamicus and leather resistance tests - DOI: 10.4025/actascianimsci.v25i1.2071

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    Petra Maria Wagner

    2003-04-01

    Full Text Available Este trabalho analisou a morfologia da pele do pacu, Piaractus mesopotamicus (Holmberg, 1887, e, após curtimento, a resistência do couro. Observou-se que a derme apresenta uma camada superficial com fibras finas, juntas e entrelaçadas, sem diferenciação quanto à disposição das mesmas e uma camada profunda, com fibras mais finas e espaçadas; e à medida que se distanciam da epiderme, os feixes de fibras tornam-se mais espessos, juntos e entrelaçados. A resistência à tração foi significativamente menor no sentido longitudinal (5,93 N/mm2 comparada ao transversal (13,81 N/mm2 em relação ao comprimento do corpo. O valor de alongamento até a ruptura foi superior (p0,05 para rasgamento progressivo. A resistência do couro à tração e alongamento foi superior no sentido transversal ao comprimento do corpo do peixe e não houve diferença para o rasgamento progressivo entre os cortes analisados (transversal e longitudinal. Sendo assim, a média da tração foi 9,87 N/mm2 e 64,59% de elongação, estando dentro dos padrões exigidos para ser utilizado na confecção de vestuário.This work study the histology of skin of Piaractus mesopotamicus (Holmberg, 1887, and after tanning, the leather resistance. Dermis showed a superficial layer with thin, united and interlaced fibers and a inner layer with thinner and spacer fibers. When this layer keeped away from epidermis, the sheaf fibers became thicker, uniter and interlacer. The resistance to tension of body length was significatively inferior in longitudinal sense (5.93 N/mm when compared with transversal sense (13.81 N/mm. The extension value until the rupture was superior (P0.05 to progressive tearing. The leather resistance to tension and extension was higher in transversal sense to body lenght of fish and there wasn’t difference to progressive tearing between the section analysed. Thus, the tension was 9.87 N/mm and 64.59% of elongation that are inside the standard require to

  17. Aeromonas hydrophila Extracelullar Products Extraction and its Effects on Tilapia Roja (Oreochromis spp. and Cachama Blanca (Piaractus brachypomus

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    M. Rodríguez

    2005-07-01

    of 128 UH/μL and a proteolitic activity of 38.4 UP/μL and produced high fish mortality and severe multiorganic lesions. Electrophoresis revealed bands from 50 to 52 kDa y 63 to 68 kDa, that could correspond to the b hemolisina or a hemolisina y other from 30 to 36 kDa that could correspond to the thermostable metalloprotease.

  18. Chronic granulomatous inflammation in teleost fish Piaractus mesopotamicus: histopathology model study

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    Wilson G Manrique

    2017-01-01

    Full Text Available Objective. This study evaluated the cell kinetic and formation of granuloma during chronic inflammation induced by Bacillus Calmette-Guérin (BCG in the skeletal muscle of Piaractus mesopotamicus, as a histopathology model to study innate immunity. Materials and methods. Sixty fish were divided in two groups: BCG-inoculated and non-inoculated fish and the inflammatory response analyzed 3, 7, 14, 21 and 33 days post-inoculation (DPI by histopathology after hematoxylin-eosin and Ziehl-Neelsen staining. Results. 3 DPI of BCG showed a diffuse inflammatory reaction mostly composed by mononuclear cells. The inflammation continued diffuse 7 DPI initiating the cellular organization surrounding the inoculum and have continued at 14 DPI with discrete presence of epithelioid-like type cells with acidophilic cytoplasm and floppy chromatin. Higher cellular organization (21 DPI surrounding the granuloma with intense peripheral mononuclear inflammatory infiltrate and nevertheless, an increase in the number of fibroblasts and macrophage-like cells was observed. The inflammatory process became less diffuse 33 DPI with formation of small amount of granuloma surrounded by the same type of reaction found in bigger granuloma. Both the young and old granuloma presented typical characteristic around the inoculum composed by a layer of epithelioid-like type cells, besides macrophages, some lymphocytes and abundant fibroblasts. Conclusions. This study showed the feasibility in the use of pacus to study chronic granulomatous inflammatory response induced by BCG, characterized by changes in the kinetics of inflammatory cells in skeletal muscle classifying as immune-epithelioid type, similar to granulomatous inflammation caused by M. marinum in teleost fish.

  19. The administration of exogenous prostaglandin may improve ovulation in pacu (Piaractus mesopotamicus).

    Science.gov (United States)

    Criscuolo-Urbinati, E; Kuradomi, R Y; Urbinati, E C; Batlouni, S R

    2012-12-01

    Based on the reports of unsuccessful ovulation in pacu (Piaractus mesopotamicus) by fish farmers and researchers undertaking artificial reproduction programs, we evaluated the use of prostaglandin F (PGF) to improve pacu ovulation. This study was conducted during two spawning seasons (2009/2010 and 2010/2011) with two samplings in the first season and one sampling in the second season. A total of 45 females was sampled in this study. The control group was injected with carp pituitary extract (crude extract, 6 mg/kg), and the treatment group received PGF (2 mL per fish in the 2009/2010 season and 5 mL per fish in the 2010/2011 season) in addition to the crude extract. In both seasons, 100% (N = 4, 2009/2010 first sampling; N = 5, 2009/2010 second sampling; and N = 3, 2010/2011) of the PGF-treated fish spawned. In contrast, 53.0% (N = 9) and 83.3% (N = 10) of the control fish spawned in the first and second samplings of the 2009/2010 season, respectively, and only 25.0% (N = 1) spawned in the 2010/2011 season. Fecundity, fertility, and hatching rates did not differ (P > 0.05) between the treated and control fish. Based on oocyte volume frequency analysis, ovaries of the control fish had more (P fish. In conclusion, administration of exogenous prostaglandin may improve the outcome of hormonally induced spawning in tropical migratory fish. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Myxosporidiosis in intensively-reared Piaractus mesopotamicus: Histopathological diagnosis by means of Ziehl-Neelsen staining

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    Wilson G. Manrique

    2012-11-01

    Full Text Available Samples of different organs from intensively-reared Piaractus mesopotamicus were collected and processed using routine histological techniques in order to produce thin sections for staining with hematoxylin-eosin and with the Ziehl-Neelsen method. Through examination under an optical microscope, myxosporidians of the genera Henneguya sp. and Myxobolus sp. were identified, respectivelyin the gills and kidneys of P. mesopotamicus. Plasmodia with immature spores of Henneguya sp. were located along the secondary lamellae, with total length of 30.45±4.84µm and width of 3.52±0.33µm. Spores of Myxobolus sp. were located in the kidneys, with total length of 8.94±0.82µm and width of 5.59±0.39µm. Histopathological analysis of the gills showed plasmodia containing spores of Henneguya sp., at intralamellar and intravascular localities, at different stages of development. Spores of Myxobolus sp. were identified in the kidneys, in the peritubular region and in the interstices and glomerulus, surrounded by melanomacrophages. Focal hemorrhage was recorded in a few cases. Ziehl-Neelsen staining allowed to identify particular features of the spores and facilitated biometry and enabled classification in comparison with hematoxylin-eosin, thus demonstrating its usefulness for histopathological diagnosis of the parasitosis.

  1. Growth, survival and bone alterations in Piaractus mesopotamicus larvae under different rearing protocols

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    David Roque Hernández

    2015-09-01

    Full Text Available The pacu (Piaractus mesopotamicus is a neotropical freshwater fish. It is one of the most important species farmed in areas of the Parana and Paraguay Rivers basins. The effects of different rearing protocols on growth, survival and incidence of skeletal malformations in pacu larvae were analyzed. A total of six experimental treatments were considered, consisting of: a semi-intensive larviculture (LS in ponds; intensive larviculture (LIn in laboratory (both LS and LIn until 60 days of life; and mixed larviculture, with 20 days of semi-intensive larviculture into cages in ponds after 14 (L1, 21 (L2, 33 (L3 or 40 (L4 days of laboratory larviculture. At the end of the experimental period, LSlarvae showed higher growth rate, with average weight values (2.28g and total length (TL-48.20mm statistically higher than the rest (P1 to L4 treatments showed intermediate growth values, without differences between them (P>0.05, while LIn presented the lowest growth (PS, that presented a significantly lower value (17.5%, PIn and L1 presented the lowest incidence. In no case, visible morphological alterations were found. This study shows that prolonging pacu rearing under laboratory conditions at high densities improves temporal availability and survival of juvenile without affecting growth or subsequent osteological development of fish.

  2. Effects of chromium supplementation on the infrapopulations of Anacanthorus penilabiatus (Monogenoidea and Piscinoodinium pillulare (Dinoflagellida parasites of Piaractus mesopotamicus (Characidae

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    Rodrigo Yudi Fujimoto

    2010-08-01

    Full Text Available This study evaluated the parasitism by Anacanthorus penilabiatus (Monogenoidea and Piscinoodinium pillulare (Dinoflagellida in the gills of "pacu", Piaractus mesopotamicus supplemented with chromium in the diet. Randomised delineation by using factorial scheme (4x2x2 for Monogenoidea and 4x2x3 for Dinoflagellate with four levels of chromium (0, 6, 12, 18mg/kg diet, two stocking densities (4kg/m³ and 20kg/m ³, two classes of length (higher and lower than 17 cm for a period of 7, 60 and 90 days, and four replicates was used. The fishes in low density which received 12 and 18mg/kg showed decreased monogeneoidea values, seven days after the experiment begin. Six, 12 and 18 mg/kg caused reduction in the dinoflagellate number in the fishes maintained at 20kg/m³. It was possible that chromium supplementation (12 e 18mg/kg favoured the fishes health by reducing Monogenoidea and Dinoflagellida number in lower and higher densities, respectively.O objetivo do trabalho foi avaliar a intensidade de parasitismo por monogenóide Anacanthorus penilabiatus e pelo dinoflagelado Piscinoodinium pillulare em pacus Piaractus mesopotamicus, cuja dieta foi suplementada com cromo. Foram utilizados dois delineamentos em esquema fatorial, consistindo de 4 níveis de cromo (0, 6, 12, 18 mgCQC/kg, duas densidades de estocagem (4 kg/m³ e 20 kg/m³ e duas classes de tamanho para monogenóide (maiores e menores de 17cm e/ou 3 períodos de coleta (7, 60 e 90 dias, com quatro repetições. Os peixes que receberam 12 e 18mg CQC/kg apresentaram diminuição de monogenóides após 7 dias de alimentação na menor densidade. Nos peixes na maior densidade, os níveis de 6, 12 e 18 mgCQC/kg ocasionou redução de dinoflagelados. Os resultados demonstraram que a suplementação com cromo (12 e 18 mgCQC/kg promoveu uma melhora na saúde dos peixes na menor e na maior densidade, respectivamente.

  3. Alterações hematológicas e histopatológicas em pacu, Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes, Characidae, Hematological and histopathological alteration in pacu Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes, Characidae after treatment with copper sulphate (CuSO4

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    Flávio Ruas de Moraes

    2002-05-01

    Full Text Available Este trabalho avaliou os valores hematológicos e glicêmicos e histopatologia de Piaractus mesopotamicus (Osteichthyes, Characidae infectados com Monogenea Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 (Dactylogyridae após tratamento com 0,50 mg/L e 1,00 mg/L de sulfato de cobre (CuSO4. A eficiência da droga sobre as infecções com Monogenea foi observada no primeiro dia após administração mas não após 8, 15 ou 30 dias do tratamento. As análises histopatológicas mostraram hiperplasia do epitélio e alterações circulatórias nas brânquias. No primeiro dia após tratamento, foram observadas alterações significativas (P4 mostraram redução da taxa de hemoglobina e do percentual de neutrófilos. No 8o dia do tratamento a dose de 1,00 mg/L provocou aumento da glicemia mas redução no percentual de linfócitos quando comparada com 0,50 mg/L. No 15o dia após tratamento com 1,00 mg/L os valores médios do volume corpuscular médio e o percentual de células granulocíticas especiais (C.G.E. decresceram mas o número de leucócitos totais aumentaram. No 30o dia após tratamento com 0,50 mg/L de sulfato de cobre houve aumento de C.G.E. e no tratamento com 1,00 mg/L o aumento foi de linfócitos.This paper evaluated the haematological and glycaemic parameters in Piaractus mesopotamicus (Osteichthyes, Characidae infected with Monogenea Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 (Dactylogyridae after treatment with 0.50 mg/L and 1.00 mg/L of copper sulphate (CuSO4. The efficacy of the CuSO4 was observed in the first day after administration but not after eight, fifteen or thirty days. The histopathological analyses showed hyperplasia of the epithelium and circulatory changes in the gills. In the first day after treatment significant changes (Pth day. Fifteen days after 1.00 mg/L treatment, values of mean corpuscular volume (MCV and special granulocitic cells (S.G.C. percentage decreased. Nevertheless, increase of

  4. Eficácia do diflubenzuron no controle de Dolops carvalhoi (Crustacea: Branchiura em jovens pacus Piaractus mesopotamicus (Osteichthyes: Characidae naturalmente infectados - DOI: 10.4025/actascianimsci.v27i2.1235 Diflubenzuron effectiveness in Dolops carvalhoi (Crustacea: Branchiura control in juvenile pacus Piaractus mesopotamicus (Osteichthyes: Characidae naturally infected - DOI: 10.4025/actascianimsci.v27i2.1235

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    Julieta Rodini Engrácia de Moraes

    2005-03-01

    Full Text Available Neste ensaio, avaliou-se a eficácia terapêutica do diflubenzuron contra o crustáceo Dolops carvalhoi (Crustacea: Branchiura em pacus Piaractus mesopotamicus Holmberg 1887 (Osteichthyes: Characidae naturalmente infestados. A droga foi aplicada três vezes na concentração de 2,0 mg/L de água, na forma de banhos com trinta minutos de duração e intervalo de 24 horas. Um grupo controle foi submetido ao mesmo procedimento, sem a adição do fármaco à água. A avaliação parasitológica revelou que a eficácia da droga foi de 97,2%. No grupo tratado houve redução da glicemia, aumento da quantidade de eritrócitos, redução do percentual de células granulocíticas especiais e aumento da quantidade de trombócitos circulantes coincidentes com a eliminação dos parasitos, quando comparado ao grupo controle. Os resultados indicam que ocorreu melhora marcante na saúde dos peixesThis research evaluated the therapeutic efficacy of diflubenzuron against Dolops carvalhoi (Crustacean: Branchiura in Piaractus mesopotamicus (Osteichthyes: Characidae naturally infested. The drug was applied three times, at a dose of 2.0 mg/L of water, in the form of baths within thirty minutes and an interval of 24 hours. A control group was submitted to the same procedure, but without pharmaco in the water. The parasitological evaluation showed that the drug effectiveness was 97.2%. In the treated group there were glycemia reduction, increase in the erythrocyte number, decrease in the percentage of special granulocytic cells and increase in the number of circulant trombocytes similar to the parasites elimination when compared to the control group. Results showed an important improvement in fish health

  5. Predação de larvas de pacu (Piaractus mesopotamicus, Holmberg por copépodes ciclopóides (Mesocyclops longisetus, Thiébaud em diferentes densidades e ambientes e com diferentes contrastes visuais Predation of pacu (Piaractus mesopotamicus, Holmberg larvae by cyclopoid copepods (Mesocyclops longisetus, Thiébaud at different densities in environments with different visual contrast

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    Carmino Hayashi

    2001-05-01

    Full Text Available O objetivo do presente trabalho foi avaliar a influência da densidade de copépodes ciclopóides (Mesocyclops longisetus na predação de larvas de pacu (Piaractus mesopotamicus em ambientes com diferentes contrastes visuais. Foram utilizadas 360 larvas de pacu (Lt = 5,77±0,23 mm e Wt = 6,57 mg, distribuídas em 24 aquários (1-L de vidro transparente, em um delineamento em blocos casualizados com oito tratamentos e três repetições, que constaram de 0, 10, 20 e 30 copépodes/L, em aquários com paredes sem revestimento ou com paredes revestidas de plástico escuro. Realizou-se a contagem, a cada uma hora, das larvas mortas e em seguida elas eram retiradas com uma pipeta. Observou-se um aumento linear nas taxas de predação (p Influence of density of cyclopoid copepods (Mesocyclops longisetus on pacu larvae (Piaractus mesopotamicus predation in environments with different visual contrast is provided. Three hundred and sixty larvae (Lt: 5.77±0.23 mm and Wt: 6.57 mg were distributed in 24 one-liter light-color-lined aquaria, in a entirely randomized design, with eight treatments and three replications, with densities 0, 10, 20 and 30 copepods/L. Similar densities were used and distributed in aquaria with dark plastic lined interior. Dead larvae were counted hourly and removed with a pipette. After three hours from the start of experiment a linear increase in predation rate (p th to the 9th observation, with smaller survival values of pacu larvae in light-colored aquaria. It may be concluded that increase in copepod density and absence of lining on walls of aquaria favor higher predation rates of copepods on pacu larvae

  6. Suplementação de lisina e metionina em dietas com baixo nível protéico para o crescimento inicial do pacu, Piaractus mesopotamicus (Holmberg Lysine and methionine supplementation in diets with low protein level for the initial growth of pacu Piaractus mesopotamicus (Holmberg

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    Adriana Patrícia Muñoz-Ramírez

    2002-04-01

    Full Text Available O objetivo deste trabalho foi estudar os efeitos da suplementação de metionina ou lisina em dietas com baixo teor protéico para o crescimento do pacu Piaractus mesopotamicus (Holmberg (Characiformes, Characidae. Foram formuladas uma dieta basal com 22% de proteína bruta (PB, 4100kcal de energia bruta (EB/kg, 0,42% de metionina e 1,16% de lisina e outras 6 dietas, com a mesma formulação básica, suplementadas com 0,2, 0,4 ou 0,6% de metionina ou lisina. Uma 8ª dieta (controle continha 26% PB, 4100kcal EB/kg, 0,48% metionina e 1,43% de lisina. As dietas foram administradas à vontade a 144 alevinos com 14,98 ± 1,16g de peso médio inicial. As médias de ganho em peso, eficiência de retenção de energia bruta e dos consumos alimentares da dieta controle mostraram-se maiores (P The objective of this research was to study the effects of methionine or lysine supplementation in diets with low protein level for growth of pacu Piaractus mesopotamicus (Holmberg (Characiformes, Characidae. Diets were formulated as a basal diet presenting 22% crude protein (CP, 4100 kcal gross energy (GE/kg, 0.42% of methionine and 1.16% of lysine and other six diets, with the same basic formulation, supplemented with 0.2%, 0.4% or 0.6% methionine or lysine. An eighth diet (control contained 26% CP, 4100 kcal (GE/kg, 0.48% methionine and 1.43% of lysine. The diets were administered ad libitum to 144 fingerlings with initial medium weight of 14.98 ± 1.16 g. Averages weight gain, gross energy efficiency retention and feed intake for the control treatment were significantly higher (P < 0.05 than those of smaller protein level diets. Averages protein retention efficiency were only higher (P < 0.01 in the diets supplemented with lysine, showing the advantages of lysine supplementation in diets with low crude protein level. A higher growth of pacu was confirmed with diets containing 26% of CP.

  7. Praziquantel, levamisol e diflubenzuron no controle de Dolops carvalhoi (Crustacea: Branchiura e Anacanthorus penilabiatus (Monogenea: Dactylogyridae em Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae Praziquantel, levamisole and diflubenzuron in the control of Dolops carvalhoi (Crustacea: Branchiura and Anacanthorus penilabiatus (Monogenea: Dactylogyridae in Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae

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    Sergio Henrique Canello Schalch

    2009-03-01

    Full Text Available Neste trabalho, avaliou-se a eficácia antiparasitária do praziquantel, levamisol e diflubenzuron administrados via oral, adicionados à ração, para pacus (Piaractus mesopotamicus infectados por Anacanthorus penilabiatus e Dolops carvalhoi. Foram utilizadas 19 caixas d'água de 300 L de capacidade, comportando 28 peixes cada. Os tratamentos foram feitos misturando os princípios ativos nas dietas. A intensidade parasitária e eficácia foram avaliadas 1 dia antes e 3, 7 e 15 dias após o início da alimentação com ração contendo diflubenzuron, levamisol e praziquantel isolados ou associados em diferentes concentrações por 7 dias. Os resultados da eficácia terapêutica sugerem que, isoladamente ou associado com levamisol e praziquantel, o diflubenzuron é eficiente contra o crustáceo D. carvalhoi, demonstrando que a eficácia dos tratamentos nos dias 3, 7 e 15 variou de 96,2 a 100%. Contra os monogenóides, as drogas não apresentaram eficácia satisfatória. Os resultados sugerem o uso do diflubenzuron para o controle de D. cavalhoi em peixes de cativeiro e em condições de quarentenário.This assay evaluated the control efficacy of diflubenzuron, praziquantel and levamisole added to the diet of pacu (Piaractus mesoptamicus infected with Anacanthorus penilabiatus and Dolops carvalhoi. 19 water tanks of 300 L capacity were utilized with 28 fish in each one. The treatments were made by mixing the active principles in the diet. The experiment was evaluated in four harvests done 1 day before and 3, 7 and 15 days after the treatment. The medicated feeding was applied for 7 days. The results of efficacy suggest that the diflubenzuron alone or associated with levamisole and praziquantel was efficient against the crustacean D. carvalhoi and the efficacy in the 3, 7 and 15 days evaluations ranged from 96,2 to 100%. Against the monogenean the drugs did not present efficacy. The results suggest the use of diflubenzuron for the control of D

  8. Effect of menthol and eugenol on the physiological responses of pacu Piaractus mesopotamicus

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    Milena Souza dos Santos Sanchez

    2014-09-01

    Full Text Available The present study the aim was evaluate induction time, recovery time and physiological responses of pacus Piaractus mesopotamicus submitted to eugenol and menthol usual doses. Were used 56 pacus, which were exposed to menthol 150 mgL-1 (n=24 and eugenol 100 mgL-1 (n=24 and the control group (n=24 which doesn’t were exposed to anesthetics. In the moment 0, 12 and 24 hours after induction were performed collection of blood in fish (n=8 for the hematologic parameters and plasma glucose evaluation. The recovery was conduced in aquariums free anesthetic, being induction and recovery times monitored. The results were submitted at analysis of variance (P<0.05 and the means when significant were compared by Tukey test (P<0.05. Both anesthetics in their respective concentrations induced fish to surgical anesthesia. There was no treatment effects on hematologic parameters, except for hemoglobin for which was observed interaction effect between factors, is significantly lower 150 mgL-1 showed significant reduction (P<0.05 of hemoglobin values 12 hours after induction, however these values remained unchanged 24 hours after anesthesia. Interaction effect (P<0.01 was observed between treatments and sampling times for the plasma glucose levels, because there was significant reduction in this levels 12 hours after anesthesia, and remained 24 hous after induction. Menthol 150 mgL-1 and eugenol 100 mgL-1 can be used safely in the pacus induction during realization of biometrics.

  9. Phenotypic plasticity associated to environmental hypoxia in the neotropical serrasalmid Piaractus mesopotamicus (Holmberg, 1887 (Characiformes: Serrasalmidae

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    María Alejandra Fernández-Osuna

    Full Text Available ABSTRACT Many South American characid fishes develop reversible dermal protuberances in the jaws to optimize aquatic surface respiration (ASR during hypoxia. To date, basic aspects of this adaptation remain unknown, mainly due to the scarcity of experimental studies. In laboratory experiments, we determined time necessary for the complete formation and reversion of these structures in Piaractus mesopotamicus , and studied comparatively behavioral, morphological, and respiratory responses along gradients of dissolved oxygen (DO concentration. Morphological changes during hypoxia consisted in dermal protuberances of lower lip, anterior border of maxillary and distal border of opercular valve, increasing the known number of structures modified. These structures developed completely in less than 6 hours and reversed in less than 3 hours. Most of observed traits showed a logistic response curve with threshold DO values between 0.90 and 2.70 mgL-1. Respiratory frequency and opercular valve development showed similar threshold values above the level of tolerance of DO, whereas ASR and dermal protuberances of the jaws showed threshold values below this level. This observation supports the functional link between these groups of behavioral and morphological traits. This study demonstrates that this species is able to modify reversibly portions of the respiratory system to optimize responses to hypoxia.

  10. Gills of juvenile fish piaractus mesopotamicus as histological biomarkers for experimental sub-lethal contamination with the Organophosphorus Azodrin®400

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    Cácia Aparecida Mendes Rudnicki

    2009-12-01

    Full Text Available Piaractus mesopotamicus is a freshwater native fish from rivers of the Paraná-Paraguay Basin and of the Pantanal region and has been used for repopulation programs in Brazil. Juvenile fishes were exposed to the sub-lethal dose of 1.08mg/L of the OP Azodrin®400 containing 0.43µL/L of the active principle monocrotophos for 96 h. A frequent pathology in the gills at all times of exposure was epithelial detachment, from minimal until 24 h of exposure, to intense after 48 h of contamination. Deformed pillar cells in the respiratory lamellae leading to irregular blood spaces and blood congestion, as well as hyperplasia and lamellar fusion were observed. These histopathologies suggested that 48 h after T0 was an important time when a reduction in the capability for gaseous exchange with consequent weakening of the fishes' condition could occur. This could impair growth and development of juveniles introduced in water bodies for repopulation programs.Piaractus mesopotamicus é um peixe de água doce encontrado na Bacia Paraná-Paraguai e na região do Pantanal, tendo sido usado em programas de repovoamento no Brasil. Peixes juvenis foram expostos por 96 horas à dose sub-letal de 1.08mg/L do organofosforado (OP Azodrin®400 que contém 0,43µL/L do principio ativo monocrotofós. A patologia freqüente nas brânquias foi o descolamento epitelial que variou de mínimo nas primeiras 24 horas a severo ou intenso após 48 horas de contaminação. Deformações e degeneração de células pilares nas lamelas respiratórias levando à formação de espaços sanguíneos irregulares e congestão sanguínea, hiperplasia e fusão lamelar também foram observadas. Sugere-se que 48 horas após o T0 é um tempo crítico após exposição a níveis subletais de OP, pois a capacidade de trocas gasosas poderá ter diminuído, levando ao enfraquecimento dos peixes. Os sintomas poderão prejudicar o desenvolvimento dos juvenis introduzidos em corpos de água em

  11. Desempenho, enzimologia e metabolismo de juvenis de pacu (Piaractus mesopotamicus) alimentados com dietas peletizadas e extrusadas com níveis médio e alto de lipídeos e carboidratos

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    Claucia Aparecida Honorato da Silva

    2008-01-01

    O objetivo desse trabalho foi avaliar as respostas bioquímicas e metabólicas em adaptação ao processamento da dieta (peletizadas e extrusadas) contendo baixo e alto nível de carboidratos e lipídeos na alimentação do pacu Piaractus mesopotamicus. Foram analisadas as características das dietas, os índices de crescimento, a eficiência de retenção dos nutrientes e da energia, o perfil de ácidos graxos presentes no filé, o tempo de trânsito gastrointestinal, digestibilidade de proteína e da energi...

  12. Haematological and histopathological analysis in South American fish Piaractus mesopotamicus parasitized by monogenean (Dactylogyridae

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    GT Jerônimo

    Full Text Available Monogeneans are the parasites mostly found on the body surface and gills of fish and can cause large losses in farmed fish. Some studies demonstrate elevated parasitic levels causing hematological alterations. But few of them relate the effects of parasitism on the hematology and histopathology of native freshwater farmed fish. This study evaluated the host-parasite relationship in pacu (Piaractus mesopotamicus parasitized by the monogenean Anacanthorus penilabiatus. Hematological and parasitological assessments were obtained in 60 fish captured in a fish farm located in Dourados, State of Mato Grosso do Sul, Central Brazil. Fish were analyzed in different categories of parasite number: class I (n=13; 0-200 parasites, class II (n=17; 201-1200 parasites; class III (n=7; 1201-2200 parasites; and class IV (n=23; more than 2200 parasites per host. The highest levels of parasitism caused significant decrease (p<0.05 in the hematocrit, red blood cells (RBC, mean hemoglobin concentration (MCHC and basophils number. Thrombocytes, mean corpuscular volume (MCV, mean corpuscular hemoglobin concentration (MCHC, monocytes, eosinophils, neutrophils and LG-PAS did not present significant difference among the parasitic levels. In contrast, increased number of total leukocytes and lymphocytes were found in highly-parasitized fish. A positive linear correlation (p<0.01 was found between the amount of parasites and fish weight. Histopathology revealed severe hyperplasia, sub-epithelial edema, fusion of the secondary lamellae, focal and multifocal necrosis in highly parasitized fish.

  13. BICULTIVO EN BIOFLOC DE CACHAMA BLANCA -Piaractus brachypomus- Y TILAPIA NILÓTICA -Oreochromis niloticus- ALIMENTADAS CON DIETAS DE ORIGEN VEGETAL

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    S. B. Brú-Cordero

    2017-01-01

    Full Text Available Se evaluó el desempeño productivo de cachama blanca y tilapia nilótica cultivadas en biofloc y alimentadas con dietas de origen vegetal. Se cultivaron 80 peces/m3 en proporción 1:1 (cachama : tilapia, con tres niveles de proteína bruta (PB: 16% (T16, 24% (T24 y 32% (T32, en tanques de 1.000 l, con aireación permanente durante 120 días. Se estimaron parámetros de crecimiento, rendimiento, calidad de agua, costos de producción y análisis proximal de los flóculos. El oxígeno disuelto se mantuvo con saturación por encima de 100% y los compuestos nitrogenados (NO2 = 0,4-0,5 mg/l, NO3 = 0,4-0,5 mg/l, NH3 = 0,2-0,3 mg/l, TAN = 2,2-2,4 mg/l no presentaron diferencias entre los tratamientos (P > 0,05. Los pesos finales de la cachama (173,5-196,2 g fueron entre dos y cuatro veces los obtenidos por la tilapia (43,0-87,9 g. El mejor rendimiento del bicultivo se obtuvo con la dieta T24 (11,4 ± 1,3 kg/m3, el cual también registró el menor FCA (0,9 ± 0,3. Producir un kilogramo de pescado costó entre COP $3.148 (T24 y COP $4.445 (T32; del cual el alimento representó entre 49,2% (T16 y 63,3% (T32 y la energía, entre 10,3% (T32 y 14,2% (T16 de los costos. El análisis proximal de los flóculos registró niveles de proteína bruta (29-36% PB adecuados para cachama y tilapia; pero con niveles bajos de lípidos (< 1,0%. El desempeño productivo y los costos de producción permiten sugerir la viabilidad que ofrece el sistema biofloc para la producción de carne de pescado con alimento de 24% PB de origen vegetal.

  14. Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470 Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470

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    Carlos Eduardo Bento Fernandes

    2011-09-01

    Full Text Available The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae, so that we always had 10 larvae of fish at each aquarium after each counting. For both fish species, there was a slight increase in consumption by the Odonate with intermediate size, but the values did not differ statistically (p > 0.05. Larvae of Odonate in the treatments with greater length presented a lower consumption (p The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae

  15. Hematologia de teleósteos brasileiros com infecção parasitária. I. Variáveis do Leporinus macrocephalus Garavelo e Britski, 1988 (Anostomidae e Piaractus mesopotamicus Holmberg, 1887 (Characidae Haematology of parasitized Brazilian teleost fishes. I. Parameters of Leporinus macrocephalus Garavelo and Britski, 1988 (Anostomidae and Piaractus mesopotamicus Holmberg, 1887 (Characidae

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    Dilermando Perecin

    1999-07-01

    Full Text Available Espécimes de Leporinus macrocephalus (piauçu e de Piaractus mesopotamicus (pacu foram colhidos em piscicultura do município de Franca (SP para avaliação dos efeitos da infecção parasitária sobre a taxa de hemoglobina e de hematócrito, a concentração de hemoglobina corpuscular média (CHCM, o fator relativo de condição (Kn e a distribuição percentual de células sangüíneas de defesa orgânica (leucócitos e trombócitos. Ambas as espécies apresentavam-se parasitadas por monogenea ou por monogenea e outros parasitas: monogenea e Trichodina sp; monogenea e Lernaea cyprinacea; monogenea e Piscinoodinium pillulare; monogenea e Ichthyophthirius multifiliis; monogenea, I. multifiliis e Trichodina sp. Os resultados demonstraram que os parâmetros estudados em L. macrocephalus e em P. mesopotamicus não foram significativamente (p > 0,05 alterados pelo parasitismo. A análise de regressão linear mostrou correlação negativa (p > 0,05 entre linfócitos e trombócitos em L. macrocephalus e correlação positiva (p > 0,01 da taxa de hemoglobina com o peso e com o comprimento total em P. mesopotamicus.Specimens of cultivated Leporinus macrocephalus (piauçu and Piaractus mesopotamicus (pacu were collected in a fishfarm at Franca, SP. Effects of parasite infection upon hemoglobin, hematocrit, mean corpuscular hemoglobin concentration (MCHC, condition factor (Kn and differential count of defense cells (leucocyte and thrombocyte were evaluated. Both fish species were parasitized by monogenean; monogenean and Trichodina sp; monogenean and Lernaea cyprinacea; monogenean and Piscinoodinium pillulare; monogenean and Ichthyophthirius miltifiliis; monogenean, I. multifiliis and Trichodina sp. Parasitism did not influence (p > 0.05 the studied haematological characteristics in L. macrocephalus and P. mesopotamicus. Linnear regression showed negative correlation (p > 0.05 between lymphocytes and thrombocytes in L. macrocephalus and positive

  16. Processamento da carne do pacu (Piaractus mesopotamicus cultivado em tanques-rede no reservatório de Itaipu - DOI: 10.4025/actascianimsci.v29i4.1018 Processing of pacu (Piaractus mesopotamicus meat from net cage farming in the Itaipu reservoir - DOI: 10.4025/actascianimsci.v29i4.1018

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    Beatriz Cristina Bencke

    2008-03-01

    Full Text Available O trabalho objetivou avaliar as características morfométricas, bromatológicas e o rendimento de cortes da carne do pacu (Piaractus mesopotamicus, cultivados em tanques-rede. Utilizaram-se 45 animais, distribuídos em três tratamentos e 15 repetições cada uma. Os tratamentos constituíram-se de animais alimentados com ração extrusada comercial (REC, resíduos de vegetal cozido (RPV e resíduos cozidos de produção pesqueira (RPP. Realizaram-se as medidas individuais dos animais de comprimento-padrão (CP, comprimento total (CT, comprimento da cabeça (CC, altura da cabeça (AC, largura do tronco (LT, comprimento do tronco (CTR, altura do tronco (AT e, a partir delas, avaliaram-se as relações morfométricas de CC/CP, CC/AC, CP/CT, LT/CTR, LT/AT e AT/CTR. Avaliaram-se os rendimentos: carcaça (RCARC, tronco limpo (TL, musculatura dorsal (MD, filé (FL, costelas (COST, nadadeiras (NAD, gordura visceral (GVISC, pele com escamas (PELE, e os teores de umidade (UM, matéria mineral (MM, proteína bruta (PB e extrato etéreo (EE dos diferentes cortes. Observaram-se maiores resultados (p This work was carried out to evalue the morphometric and chemical characteristics, as well as the meat cut yields from pacu (Piaractus mesopotamicus reared in net cages. Forty-five specimens were used, distributed in three treatments and 15 replications. The treatments consisted of animals fed with commercial extruded ration (CER, vegetal by-products (VBP and fishery by-products (FBP. Individual morphometric characteristics were measures in terms of standard length (SL, total length (TL, head length (HL head height (HH, body width (BW, body lenght (BL, body height (BH, to evaluate the morphometric ratio of HL/SL, HL/HH, SL/TL, BW/BL, BW/BH and BH/BL. Next, the carcass (CARC, clean body (CB, dorsal muscle (DM, fillet (FL, ribs (RIB, fin (FIN, visceral fat (VISCF, skin with scales (SKIN, as well as the levels of moisture (M, ash (ASH, crude protein (CPB and fat

  17. Cultivo de cachama blanca en altas densidades y en dos sistemas cerrados

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    Germán Poleo

    2011-04-01

    Full Text Available El objetivo de este trabajo fue evaluar la tolerancia de la cachama blanca, Piaractus brachypomus, a cultivos en altas densidades en sistemas cerrados. Novecientos alevines de 44,3±26 g de peso, se distribuyeron en seis tanques de concreto, con 4,8 m³ de agua. Tres tanques presentaron cero recambio de agua (SCR, y en otros tres, el agua se hizo circular a través de un bioclarificador (SRA. Ambos tratamientos presentaron fuerte aireación para mantener los sólidos en suspensión y suministrar aire. Los peces se alimentaron a saciedad con pienso comercial por 192 días. Los parámetros de calidad de agua como: oxígeno disuelto, amonio total, nitritos, nitratos, alcalinidad, dureza, temperatura y pH, se midieron semanalmente. Los peces en el SCR crecieron a una tasa de 2,34±0,05 g por día, y tuvieron conversión alimenticia de 1,5±0,06, densidad final de 12,96±0,53 kg m-3, y peso final de 449,5±99 g. En el SRA, los peces crecieron 2,33±0,03 g por día, con conversión alimenticia de 1,6±0,07, densidad final de 12,13±1,12 kg m-3, y peso final de 446,5±10 g. La cachama blanca puede ser cultivada en sistemas cerrados con cero recambio de agua en altas densidades.

  18. Aloe vera enhances the innate immune response of pacu (Piaractus mesopotamicus) after transport stress and combined heat killed Aeromonas hydrophila infection.

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    Zanuzzo, Fábio S; Sabioni, Rafael E; Montoya, Luz Natalia F; Favero, Gisele; Urbinati, Elisabeth C

    2017-06-01

    In this study, pacu (Piaractus mesopotamicus) were fed with diets containing Aloe vera for 10 days prior to transport stress and infection with heat killed Aeromonas hydrophila. A. vera is popular around the world due to its medicinal properties, including immunostimulatory effects which was observed in this study. The results show that transport causes immunosuppression, an effect that was prevented by A. vera. Specifically, A. vera prevented reductions of both leukocyte respiratory burst and hemolytic activity of complement system caused by transport. Further, fish fed with A. vera also showed significantly higher leukocyte respiratory burst, serum lysozyme concentrations and activity of complement system 24 h after bacterial infection. Additionally, we observed that A. vera may modulate the innate response through activation of complement system during bacterial immune stimulation. In summary, A. vera extract enhanced innate immune parameters and consequently the ability of fish to cope with pathogens following transport stress. These findings show that A. vera has promise for use in aquaculture and add further evidence that medicinal herbs added to fish feed assist to prevent disease outbreaks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Individual, spatial and inter-sex variation in somatic growth: a study of Piaractus mesopotamicus (Characiformes: Serrasalmidae, a long-distance freshwater Neotropical migratory fish

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    Luzia da S. Lourenço

    2017-06-01

    Full Text Available ABSTRACT Growth is a fundamental biological process, driven by multiple endogenous (intra-individual and exogenous (environmental factors that maintain individual fitness and population stability. The current study aims to assess whether individual, spatial (headwaters and floodplains and inter-sex variation occurs in the growth of Piaractus mesopotamicus in the Cuiabá River basin. Samples were collected monthly from July 2006 to July 2007, at two areas in the Cuiabá River basin (headwaters and floodplain. Three growth models (individuals; individuals and sex factors; individuals and areas factors were developed and compared the fish growth parameters using Akaike information criterion (AIC. The best fit to the length-at-age data was obtained by a model that considered individual variation and sex. The theoretical maximum average length ( L∞ was 64.99 cm for females, and 63.23 cm for males. Females showed a growth rate (k of 0.230 yr-1and males of 0.196 yr-1. Thus, could be concluded that individual variability and sex were the main sources of variation in P. mesopotamicus somatic growth parameters.

  20. Effect of ractopamine on the chemical and physical characteristics of pacu(Piaractus mesopotamicus steaks

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    L.M.F.S. Oliveira

    2014-02-01

    Full Text Available The objective was to evaluate the use of ractopamine (RAC in the diet for pacu (Piaractus mesopotaminus in the finishing phase on some quality parameters of the fillets. Thirty-five animals weighing 0.868±0.168kg were distributed in a completely randomised design with five treatments (0.0 - control; 11.25, 22.50, 33.75 and 45 ppm of RAC and seven replicates with two fillets obtained from the same animal. The diets were isocaloric and isoprotein and experimental time was 90 days. RAC did not affect (P>0.05 the initial pH or ph after 24 hours of the fillets. Compared to the control, RAC increased (P<0.05 the moisture content of the fillets in natura and lipid oxidation of samples stored for 12 days in the refrigerator or freezer for 60 days. The RAC in 11.25 ppm reduced (P<0.05 the lipid content, while 45 ppm reduced (P<0.05 the crude protein in the fillets. Considering only RAC, there was a linear increase (P<0.05 in the lipid content (P<0.05 and a linear reduction in crude protein and weight loss after cooking the fillets. There was a quadratic effect (P<0.05 on the ash content, weight loss and lipid oxidation in fillets stored in the refrigerator or freezer. A RAC dose of 33.75 ppm resulted in a lower lipid oxidation index. In conclusion, ractopamine at 11.25 ppm is effective for reducing the fat content in fillets of pacu, although it increases the formation of peroxides in samples kept in the freezer for longer than 60 days. At 33.75 ppm, ractopamine is effective in reducing the effect of oxidation during storage in the refrigerator or freezer.

  1. The role of the vagus nerve in the generation of cardiorespiratory interactions in a neotropical fish, the pacu, Piaractus mesopotamicus.

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    Leite, Cleo Alcantara Costa; Taylor, E W; Guerra, C D R; Florindo, L H; Belão, T; Rantin, F T

    2009-08-01

    The role of the vagus nerve in determining heart rate (f(H)) and cardiorespiratory interactions was investigated in a neotropical fish, Piaractus mesopotamicus. During progressive hypoxia f(H) initially increased, establishing a 1:1 ratio with ventilation rate (f(R)). Subsequently there was a hypoxic bradycardia. Injection of atropine abolished a normoxic inhibitory tonus on the heart and the f(H) adjustments during progressive hypoxia, confirming that they are imposed by efferent parasympathetic inputs via the vagus nerve. Efferent activity recorded from the cardiac vagus in lightly anesthetized normoxic fish included occasional bursts of activity related to spontaneous changes in ventilation amplitude, which increased the cardiac interval. Restricting the flow of aerated water irrigating the gills resulted in increased respiratory effort and bursts of respiration-related activity in the cardiac vagus that seemed to cause f(H) to couple with f(R). Cell bodies of cardiac vagal pre-ganglionic neurons were located in two distinct groups within the dorsal vagal motor column having an overlapping distribution with respiratory motor-neurons. A small proportion of cardiac vagal pre-ganglionic neurons (2%) was in scattered positions in the ventrolateral medulla. This division of cardiac vagal pre-ganglionic neurons into distinct motor groups may relate to their functional roles in determining cardiorespiratory interactions.

  2. Parâmetros sangüíneos de pacu Piaractus mesopotamicus (Holmberg, 1887 alimentados com dietas suplementadas com cromo trivalente em duas densidades de estocagem - DOI: 10.4025/actascianimsci.v29i4.1019 Hematological parameters of pacu Piaractus mesopotamicus (Holmberg, 1887 fed diets supplemented with trivalent chromium in two stocking densities - DOI: 10.4025/actascianimsci.v29i4.1019

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    Flávio Ruas de Moraes

    2008-03-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da suplementação com cromo trivalente (0, 6, 12 e 18 mg kg-1 de ração sobre as variáveis hematológicas de Piaractus mesopotamicus, mantidos em duas densidades de estocagem (4 e 20 kg m-3. Os mantidos na maior densidade e alimentados com dietas suplementadas com 0 e 6 mg de cromo kg-1 apresentaram redução do número de linfócitos circulantes, sugerindo má adaptação a essa condição de alta densidade. Nas dietas suplementadas com 12 e 18 mg kg-1, tal efeito não foi observado, porém verificou-se aumento do número de trombócitos no tratamento com 12 mg de cromo kg-1. A inexistência de diferença significativa entre os tratamentos, aos 30 dias, sugere a adaptação dos peixes ao tipo de alimento e à situação de alta densidade. Portanto, nas condições deste ensaio, a suplementação com 12 e 18 mg de cromo kg-1 é interessante como estratégia alimentar durante 15 dias.This work evaluated the effects of chromium supplementation on the hematological parameters of Piaractus mesopotamicus Holmberg, 1887 maintained in two stocking densities. Fish were fed diets supplemented with 0, 6, 12 and 18 mg trivalent chromium kg-1 dry ration and maintained at 4 and 20 kg m-3. The fish under high stocking density and fed diets supplemented with 0 and 6 mg kg-1 showed reduction in the number lymphocytes, which suggests non-adaptation to this condition of high density. This was not observed in fish fed diets supplemented with 12 and 18 mg chromium kg-1, but an increase in the number of thrombocytes was evident. The lack of difference between treatments after 30 days may suggest a possible adaptation of fish to the situation. It can be added that supplementation with 12 and 18 mg chromium kg-1 is an interesting feeding strategy for a period of 15 days.

  3. Análise da degradação de dieta microencapsulada por larvas de pacu (Piaractus mesopotamicus, Holmberg, 1887 através de microscopia eletrônica de varredura - DOI: 10.4025/actascianimsci.v25i1.2088 Degradation analysis of microencapsulated diet in pacu (Piaractus mesopotamicus Holmberg, 1887 larvae intestine through scanning electron microscopy (SEM - DOI: 10.4025/actascianimsci.v25i1.2088

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    Maria Célia Portella

    2003-04-01

    Full Text Available Este trabalho teve como objetivo analisar o grau de degradabilidade de dietas microencapsuladas por larvas de pacu (Piaractus mesopotamicus, através da microscopia eletrônica de varredura. Os seguintes tratamentos alimentares foram testados: AMD - larvas alimentadas por 6 dias, com náuplios de Artemia, com transição brusca para dieta microencapsulada; C6MD - alimentação inicial com Artemia por 6 dias, 6 dias de co-alimentação e o restante do tempo (8 dias somente com dieta microencapsulada; e C9MD - idêntico ao tratamento anterior, porém, com 9 dias de co-alimentação. O conteúdo presente no trato digestório das larvas foi coletado e processado para análise em microscópio eletrônico de varredura. Os grânulos provenientes das larvas do tratamento de transição brusca (AMD possuíam poucas áreas de degradação, semelhantes às dietas secas. Já as dietas coletadas das larvas durante o período de co-alimentação possuíam uma maior área degradada. Os resultados sugerem uma influência dos náuplios de Artemia sobre a degradação das dietas microencapsuladas.This research analyzed the microencapsulated diet degradation in pacu (Piaractus mesopotamicus larvae intestine. The pacu larvae received the following feeding treatments: AMD- larvae fed initially Artemia nauplii for six days, followed by microencapsulated diet; C6MD- larvae fed initially Artemia for six days, followed by six days of co-feeding and the rest of the experiment (8 days with microencapsulated diet; C9MD- larvae fed initially Artemia for six days, followed by nine days of co-feeding and the rest of the experiment (5 days with microencapsulated diet. The pacu digestive tract contents were removed, processed and analyzed under scanning electronic microscopy. Diets from AMD larvae treatment showed few degradation areas, when compared to original dry diets. On the other hand, diets removed during co-feeding period showed the highest degradation areas. The

  4. Hook selectivity of the pacu Piaractus mesopotamicus (Holmberg, 1887 in the Pantanal, the state of Mato Grosso do Sul, Brazil

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    J. Peixer

    Full Text Available The Pacu Piaractus mesopotamicus is the most captured fish species in the Pantanal, Mato Grosso do Sul State, and since 1994, its maximum sustainable yield had already been exceeded. Its capture is carried out only by hooks, as mesh gears are forbidden either for professional or for recreational fishing. The aim of this study was to determine selectivity for different hook sizes used in P. mesopotamicus fishing and to verify which sizes capture only adults. Data were collected in the rivers Miranda, Aquidauana, and Vermelho, in January, March, and April 2002. Six longlines with eight hook sizes were used and we adopted the hook opening as a measure related to selectivity. Different hooks captured individuals of the same length and their medians were similar, evidencing the great overlap among sizes. Regression results showed no significant relationship between ln[c2 (l/c1 (l] and total length of captured individuals. In addition, the Kolmogorov-Smirnov test also did not detect significant differences in the size of captured fish. Several hypotheses, such as the selectivity models, shape of selection curves, scarcity of large fishes, and behavior are used in order to explain the absence of hook selectivity for this species. Size of recruitment for this gear was 28 cm of total length, when individuals are still immature.

  5. Eficácia do florfenicol e da oxitetraciclina no controle de Aeromonas hydrophila em pacu (Piaractus mesopotamicus

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    S.P. Carraschi

    2011-06-01

    Full Text Available Determinou-se a concentração eficaz de oxitetraciclina (OTC e florfenicol (FFC no tratamento de Aeromonas hydrophila em pacu (Piaractus. mesopotamicus. Os pacus foram submetidos à captura duas vezes ao dia por quatro dias e em seguida foram infectados com A. hydrophila (2,4x10(7 bactéria mL-1. Os tratamentos utilizados foram: controle sem infecção (CSI, controle com infecção (CCI e tratados com 110,0; 140,0 e 170,0mgOTC.kg-1, e 5,0; 10,0 e 15,0mgFFC.kg-1. As variáveis de qualidade da água foram monitoradas diariamente. Após o tratamento, no CSI dos dois testes, ocorreu 100% de sobrevivência. Nos testes com OTC, no CCI, a sobrevivência foi de 29,2%; em 110,0mg.kg-1, 37,5%; em 140,0mg.kg-1, 29,2%; e em 170,0mg.kg-1, 50,0%. Nos testes com FFC, foi eficaz com 10,0mg.kg-1, e no CCI a sobrevivência foi de 76,9%; em 5,0mg.kg-1, 81,81%; em 10,0mg/L.kg-1, 100% e em 15,0mg.kg-1, 87,5%. A OTC, em concentrações de até 170,0mg.kg-1 de ração, não é eficaz para o controle de A. hydrophila em pacu, e o FFC é eficaz na concentração de 10,0mg.kg-1 e ambos não alteram as variáveis de qualidade de água.

  6. Histopatologia de fígado, rim e baço de piaractus mesopotamicus, prochilodus lineatus e pseudoplatystoma fasciatum parasitados por myxosporídios, capturados no Rio Aquidauana, Mato Grosso do Sul, Brasil Histopathology of liver, kidney and spleen of Piaractus mesopotamicus, Prochilodus lineatus and Pseudoplatystoma fasciatum infected by myxosporean parasite, caugth in Aquidauana River, Mato Grosso do Sul, Brazil

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    Cristiane M. de Campos

    2008-12-01

    Full Text Available Este estudo descreveu a histopatologia de rim, baço e fígado de Piaractus mesopotamicus, Prochilodus lineatus e Pseudoplatystoma fasciatum, parasitados por mixosporídios, capturados no Rio Aquidauana, MS. Após necropsia, amostras do fígado, rim cefálico e baço foram colhidas, fixadas em formalina a 10 % tamponada e processadas de acordo com a rotina histológica. Os cortes foram feitos à espessura de 5 μm e corados com hematoxilina-eosina. Foram encontrados Myxobolus porofilus em P. lineatus, M. colossomatis em P. mesopotamicus e Myxobolus spp. nas três espécies de hospedeiros. Cistos de mixosporídios no exame histopatológico foram vistos no fígado e baço de P. mesopotamicus. Mais de 50% das amostras de fígado de P mesopotamicus e P lineatus apresentou hepatodistrofia difusa. Mais de 80 % das amostras de fígado de P. fasciatum apresentou formações hialinas concêntricas e esteatose em 50% das amostras. Em 95,23 % das amostras de rins de P. mesopotamicus, foram observadas alterações teciduais, e em mais de 60 % dos casos nefrodistrofia difusa moderada e congestão de sinusóides glomerulares. Alterações teciduais nas amostras de rins de P. lineatus foram observadas em menos de 20 % da amostra. No baço dos peixes ora examinados não foram encontradas lesões dignas de relato.Histological analysis of kidney, spleen and liver of Piaractus mesopotamicus, Prochilodus lineatus and Pseudoplatystoma fasciatum, infected by myxosporean, caugth in Aquidauana river, MS, was studied. After necropsy, samples of liver, previous kidney and spleen were fixed in 10 % buffered formalin and processed followed histological routine methods. Sections of 5 μm were stained with hematoxylin and eosin. Myxobolusporofilus, M. colossomatis and were found in P. lineatus, in P. mesopotamicus respectively and Myxobolus spp. Were also found in all three species of fish. Myxosporideans cysts in the liver and spleen of P mesopotamicus were also related. Up

  7. Aging and growth parameter from the Piaractus mesopotamicus (pacu from the Cuiabá river, Mato Grosso, Brazil

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    Angela M. Ambrosio

    2014-12-01

    Full Text Available This study has aims to determine the age and to estimate the growth parameters using scales of the species. Individuals of Piaractus mesopotamicus (Holmberg, 1887 used in this study were captured in the commercial fishery conducted in the region, along the year 2006. The model selected to express the growth of the species was the von Bertalanffy Sl= Sl∞*[1-exp-k(t-to]. To determine if scales are suitable for studying the growth of pacu, we analyzed the relation between standard length (Sl and the radius of the scales through linear regression. The period of annuli formation was determined analyzing the variations in the marginal increment and evaluating the consistency of the readings through the analysis of the coefficient of variations (CVs for the average standard lengths of each age (number of rings observed in the scales. The relationship between Ls of the fish and the radius of the scales showed that scales can be used to study the age and growth of P. mesopotamicus (R= 0.79. CVs were always below 20%, demonstrating the consistency of the readings. Annuli formation occurred in February, probably related to trophic migration that occurs in this month in the region. Equations that represents the growth in length obtained for P. mesopotamicus are Sl=50.00*[1-exp-0.18(t-(-3.00] for males and Sl=59.23*[1-exp-0.14(t-(-3.36] for females. The growth parameters obtained in this study were lower compared to other studies previously conducted for the same species and can related to overexploitation that species is submitted by fishing in the region. These values show also that females of pacu attain greater asymptotic length than males that growth faster.

  8. Relação parasito-hospedeiro em peixes de pisciculturas da região de Assis, Estado de São Paulo, Brasil. 2. Piaractus mesopotamicus (Holmberg, 1887 = Host-parasite relationship of fishes from fish farm in Assis region, São Paulo State, Brazil. 2. Piaractus mesopotamicus (Holmberg, 1887

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    Maria de los Angeles Perez Lizama

    2007-10-01

    Full Text Available Piaractus mesopotamicus (Holmberg, 1887 é uma das espécies nativas mais difundidas em pisciculturas no Brasil. Este estudo foi realizado em três pisciculturas do Estado de São Paulo, durante os meses de fevereiro a dezembro de 2004. Oitenta e três espécimes (92,2% estavamparasitados por pelo menos uma espécie de parasito. Oito espécies de ectoparasitos foram registradas. Anacanthorus penilabiatus, A. spatulathus e Mymarothecium sp. 2 foram classificadas como centrais, e Mymarothecium sp. 1, secundária. As demais foram consideradas satélites. Foi possível evidenciar que, apesar de as espécies serem altamente prevalentes, poucas delas foram abundantes. Anacanthorus penilabiatus apresentou correlação negativa e significativa entre a abundância de parasitismo e o comprimento-padrão do hospedeiro, na propriedade do município de Tarumã, Estado de São Paulo. Mymarothecium sp. 2 apresentou correlação positiva significativa na piscicultura de Cândido Mota, Estado de São Paulo. Neste estudo, os resultados do fator de condição relativo demonstram que somente na propriedade de Palmital, Estado de São Paulo, ocorreu correlaçãosignificativa entre o Kn e a abundância de parasitismo para algumas espécies. Anacanthorus penilabiatus e A. spatulathus apresentaram-se correlacionadas positivamente com a relação hepatossomática naspisciculturas dos municípios de Tarumã e Cândido Mota, Estado de São Paulo. Em se tratando da relação esplenossomática, somente a espécie de ergasilídeo apresentou-se negativa e significativamente correlacionada em Cândido Mota, Estado de São Paulo.Piaractus mesopotamicus (Holmberg, 1887 is one of the most abundant native species in fish farmings in Brazil. This study was conducted in three fish farmings in São Paulo State, during February and December, 2004. Eighty-three specimens (92.2% were parasitized by at least one parasite species. Eight species of ectoparasites were registered

  9. Aerocistite aguda induzida por tioglicolato, lipolisacarídeo e Aeromona hydrophila inativada em Piaractus mesopotamicus: efeitos hematológicos

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    Julieta Rodini Engrácia de Moraes

    2012-10-01

    Full Text Available Os efeitos da injeção de tioglicolato, lipolissacarídio de Escherichia coli e Aeromonas hydrophila inativada na bexiganatatória de pacus, Piaractus mesopotamicus (Characidae foram avaliados quanto às respostas de células vermelhas,leucócitos e trombócitos do sangue. Ensaios quantitativos de eritrócitos, leucócitos e trombócitos foram realizados6, 24 e 48 h após os estímulos e comparados com peixes que receberam solução salina 0,65% pela mesma via. Peixes inoculados com A. hydrophila apresentaram redução do número de eritrócitos e da taxa de hemoglobina enquanto ohematócrito aumentou 6 h após o estímulo. Os resultados mostraram que o tioglicolato e o LPS também induziram redução da hemoglobina e aumento do hematócrito. A contagem de trombócitos diminuiu 6 h após a inoculação deA. hydrophila inativada e aumentou 48 horas após a injeção de LPS. A contagem de leucócitos aumentou 6 h após ainoculação de A. hydrophila enquanto a de linfócitos a leucócitos granulares PAS positivos (PAS_LG diminuiu 24 hdepois. Peixes injetados com tioglicolato o LPS apresentaram aumento do número de LG_PAS em relação aos inoculadoscom A. hydrophila inativada ou grupo controle. A contagem de monócitos não foi afetada pelos diferentes agentes.

  10. Influência da adição de iodeto de potássio e citrato de sódio na qualidade do sêmen de pacu (Piaractus mesopotamicus - Holmberg, 1887 The effects of potassium iodide and sodium citrate on semen quality of pacu (Piaractus mesopotamicus

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    Alexandre Nízio Maria

    2004-02-01

    Full Text Available Atualmente, tem-se dado maior atenção ao desenvolvimento de tecnologias para estocagem de sêmen de peixes em curto prazo, por dias ou semanas, utilizando diluentes de sêmen que não ativem a motilidade espermática. Essa técnica é indicada em piscicultura para facilitar a reprodução artificial ou aumentar sua eficiência. Conduziu-se este trabalho com o objetivo de verificar o efeito do diluidor BTS (Beltsville Thawing Solution - MINITUB® na qualidade do sêmen de pacu, após a coleta, enriquecido com iodeto de potássio e com citrato de sódio. Foram utilizados seis reprodutores de pacu (Piaractus mesopotamicus submetidos à indução hormonal e liberação dos gametas, manualmente. O sêmen coletado de cada macho foi dividido em três frações, as quais receberam diluição (1:3 com o diluidor 1 (BTS 5% + iodeto de potássio 0,16%, diluidor 2 (BTS 5% + citrato de sódio 1,28% e uma fração não diluída (controle. A ativação espermática foi realizada com água destilada, e, a seguir, foram avaliadas as taxas e duração da motilidade espermática, cujos valores médios respectivos foram de 95,00 ± 3,16% e 486,83 ± 314,55 segundos para o sêmen in natura, 80,00 ± 9,49% e 221,50 ± 207,89 segundos para o sêmen com o diluidor 1 e 80,00 ± 11,40% e 320,66 ± 181,14 segundos para o sêmen no diluidor 2. Em seguida, foram coletadas amostras para a avaliação da concentração espermática, que obteve um valor médio de 13,89 ± 1,26 x 10(9/mL. Pelas análises estatísticas, verificou-se que não houve diferença significativa na duração da motilidade (P>0,05 entre o sêmen “in natura” e os diluidores 1 e 2. A motilidade espermática foi estatisticamente melhor (PCurrently, it has been given a special attention to developing technologies for short-term storage of fish semen, for a few days to weeks, using extenders of semen that do not activate the sperm motility. The short-term storage technique is indicated for fish culture

  11. Processamento da carne do pacu (Piaractus mesopotamicus cultivado em tanques-rede no reservatório de Itaipu = Processing of pacu (Piaractus mesopotamicus meat from net cage farming in the Itaipu reservoir

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    Robie Allan Bombardelli

    2007-10-01

    Full Text Available O trabalho objetivou avaliar as características morfométricas, bromatológicas e o rendimento de cortes da carne do pacu (Piaractus mesopotamicus, cultivados em tanquesrede. Utilizaram-se 45 animais, distribuídos em três tratamentos e 15 repetições cada uma.Os tratamentos constituíram-se de animais alimentados com ração extrusada comercial (REC, resíduos de vegetal cozido (RPV e resíduos cozidos de produção pesqueira (RPP. Realizaram-se as medidas individuais dos animais de comprimento-padrão (CP,comprimento total (CT, comprimento da cabeça (CC, altura da cabeça (AC, largura do tronco (LT, comprimento do tronco (CTR, altura do tronco (AT e, a partir delas, avaliaram-se as relações morfométricas de CC/CP, CC/AC, CP/CT, LT/CTR, LT/AT e AT/CTR. Avaliaram-se os rendimentos: carcaça (RCARC, tronco limpo (TL, musculaturadorsal (MD, filé (FL, costelas (COST, nadadeiras (NAD, gordura visceral (GVISC, pele com escamas (PELE, e os teores de umidade (UM, matéria mineral (MM, proteína bruta (PB e extrato etéreo (EE dos diferentes cortes. Observaram-se maiores resultados (pThis work was carried out to evalue the morphometric and chemical characteristics, as well as the meat cut yields from pacu (Piaractusmesopotamicus reared in net cages. Forty-five specimens were used, distributed in three treatments and 15 replications. The treatments consisted of animals fed with commercial extruded ration (CER, vegetal by-products (VBP and fishery by-products (FBP. Individual morphometric characteristics were measures in terms of standard length (SL, total length (TL, head length (HL head height (HH, body width (BW, body lenght (BL, body height (BH, to evaluate the morphometric ratio of HL/SL, HL/HH, SL/TL, BW/BL, BW/BH and BH/BL. Next, the carcass (CARC, clean body (CB, dorsal muscle (DM, fillet (FL, ribs (RIB, fin (FIN, visceral fat (VISCF, skin with scales (SKIN, as well as the levels of moisture (M, ash (ASH, crude protein (CPB and fat (FAT

  12. Toxicidad aguda del sulfato de cobre (CuSO4) en alevinos de cachama blanca (Piaractus brachypomus) bajo condiciones de aguas blandas

    DEFF Research Database (Denmark)

    Velasco-Santamaría, Yohana M.; Gómez-Manrique, Wilson; Calderón-Bernal, Juan M.

    2006-01-01

    of 55 and 90% respectively. Likewise, these groups presented a moderate increase in mucus  production at branchial level accompanied by clinical disnea. Interlamellar hyperplasia and severe lamellar fusion, as well as gill congestion, were observed microscopically in those exposed to 4.00 ppm...

  13. Influência de diferentes níveis de vitamina C na ração sobre parâmetros hematológicos de alevinos de Piaractus mesopotamicus Holmberg (Osteichthyes, Characidae Influence of different levels of vitamin C in the ration on the haematological parameters of Piaractus mesopotamicus Holmberg (Osteichthyes, Characidae fries

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    Maurício Laterça Martins

    1995-09-01

    Full Text Available Haematological changes in ascorbic acid deficient fishes, observed by some authors, awoked the interest in the haematological response of pacu, Piaractus mesopotamicus. The present work studied the influence of different levels of ascorbic acid (vitamin C in the ration on the haematological parameters of pacu. Fishes at the beginning of the experiment, presented average body weight 8.64±1.62g and 6.15±0.33cm standard length, were fed with diets containing 0. 50, 100 and 200mg ascorbic acid/kg dry ration. The present work was developed for a period of 24 weeks at the Fish Nutrition Laboratory of Aquaculture Center of Universidade Estadual Paulista (Unesp, Jaboticabal (São Paulo. The fishes were distributed by the completely randomized design in 20 aquaria of 100 liters capacity with six animals in each and five fold treatment. Condutivity, alcalinity. pH and oxigen were measured weekly and temperature daily. The blood colect was done in 60 anesthetized fishes with 50mg MS-222/1. The results suggests that 50mg ascorbic acid/kg dry ration improved the mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and decreased haematocril in unsupplemented fishes, although not differing significantly (P>0.05. The erytrocyte diameter indicated the presence of macrocytic cells in unsupplemented fishes (P<0.05 and the regression analysis showed too reduced neutrophils in unsupplemenled ones, 50mg ascorbic acid/kg dry ration supplementation was enough to development and haematological responses. Furthtermore, the optimum level to the growth is 139mg vitamin C/kg dry ration (P<0.05.

  14. EVALUACIÓN DE LA RESTRICCIÓN ALIMENTICIA SOBRE EL DESEMPEÑO PRODUCTIVO Y FISIOLÓGICO EN JUVENILES DE CACHAMA BLANCA, Piaractus brachypomus, EN CONDICIONES DE LABORATORIO

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    L. Rodríguez

    2011-01-01

    muscular de proteína y energía. En cuanto al diseño experimental, este fue completamenteal azar, con cuatro tratamientos y cuatro repeticiones, cada una con cuatroindividuos. Se seleccionaron 64 individuos con 58,40 ± 6,56 g de peso (P y 14,65 ±0,75 cm de longitud total (LT, distribuidos aleatoriamente en 16 acuarios y sometidosdurante ocho semanas a los siguientes tratamientos: de control (T0: alimentación diaria;tratamiento 1 (T1: un día de ayuno y uno de alimentación; tratamiento 2 (T2:tres días de ayuno y dos días de alimentación, y tratamiento 3 (T3: dos días de ayunoy tres de alimentación. Se utilizó alimento de 35% de proteína, suministrado al 3%de la biomasa total dos veces al día. Al culminar el periodo experimental, los animalesexperimentales se anestesiaron y se les tomaron muestras de sangre para evaluar diferentesparámetros metabólicos y hormonales. Posteriormente, se sacrificaron, pesarony midieron; luego, se pesaron sus vísceras y una porción de músculo blanco se obtuvopara determinar el contenido de proteína y energía. Al final del ensayo, se calculó la sobrevivencia. Luego, de acuerdo con los resultados,se concluyó que no hubo diferencias significativas en la mayoría de los parámetrosanalizados, por lo que se infiere que los juveniles de cachama blanca son capaces deadaptarse metabólicamente a la carencia parcial de alimento y optimizar la respuesta en su desempeño.

  15. [Nutritional characterization of produced fish for human consumption in Bucaramanga, Colombia].

    Science.gov (United States)

    Perea, Aide; Gómez, Elieth; Mayorga, Yamile; Triana, Cora Yohanna

    2008-03-01

    This research involves the nutritional characterization of the most commonly cultivated fish in the region. The species under study were: Rainbow trout (Salmo gairdnerii), tilapia roja (Oreocliromis sp), cachama blanca (Piaractus brachypomus), bocachico (Prochilodus reticulatus magdalenae) and catfish (Pseudoplatystoma faciatum). A sea fish, coho Salmon (Oncorhynchus kisutch), was used as reference because it is the imported species most used in the region, and it also contains n-3 fatty acids. For each fish sample moisture, ash, protein content, total fat, minerals (iron, calcium and phosphorous) and a fatty acid profile were determined. Results show a total protein content in between 16.4 and 22.6 g/100 g fillet for fresh water fish. Total fat amounts for trout are the highest (8.1 g/100 g fillet), while catfish has the lowest fat content (0.4 g/100 g fillet). Trout was found to be the most important source of n-3 fatty acids (EPA+DHA) and phosphorous, with values ranging from 0.25% to 0.52%, and 250 to 346 mg/100 g fillet, respectively. Catfish and trout exhibited the highest iron content, with values ranging from 3 to 6mg/100 g fillet. Salmon, on the other hand, showed a high n-3 fatty acid content of 1.16% to 2.25%, when compared to fresh water fish. Calcium content is low in all species under scrutiny. Fresh water fish, other than trout, show no significant amount of n-3 fatty acids. However, all of them are a good source of protein. The obtained results allowed to determine the profile of oily acids of produced fish for human consumption in the region, demonstrating that the trout is the species with major quantity of oily acids n-3 specially DHA and of the minerals the phosphorus. Other species (kinds) catfish, bocachico, tilapia and cachama, are not a source of oily acids n-3, but they are an important source of protein.

  16. Características hematológicas, bioquímicas e biométricas de Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae oriundos de cultivo intensivo - DOI: 10.4025/actascibiolsci.v26i2.1647 Hematological, biochemical and biometric characteristics of Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae, reared in captivity - DOI: 10.4025/actascibiolsci.v26i2.1647

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    Marcos Tavares Dias

    2004-04-01

    Full Text Available O estudo das características sangüíneas pode fornecer subsídios importantes para o diagnóstico e prognóstico das condições mórbidas em populações de peixes e, contribuir para a compreensão da fisiologia comparativa, relação filogenética, condições alimentares e outros parâmetros ecológicos. Foram estudados no teleósteo Piaractus mesopotamicus o eritrograma, leucograma, trombograma, a glicemia, o cortisol, a relação hepatosomática e a relação esplenosomática. Os valores da relação hepatosomática variaram de 0,67% a 2,79%, a relação esplenosomática de 0,011% a 0,108%, número de eritrócitos de 1,870 a 4,590 x 106/µL de sangue, concentração de hemoglobina de 5,7 a 12,1g/dL, hematócrito de 24,0% a 40,0%, volume corpuscular médio de 98,0 a 174,0fL, concentração da hemoglobina corpuscular média de 19,1 a 34,2g/dL, glicose plasmática de 40,6 a 89,2mg/dL e cortisol plasmático de 4,73 a 110,5ng/dL. O número de trombócitos totais variou de 12160,0 a 89280,0/µL de sangue e leucócitos de 2019,0 a 47473,0/µl de sangue. Na contagem diferencial de leucócitos foram observados 54,1% de linfócitos; 10,9% de neutrófilos; 10,3% de monócitos; 9,9% de leucócitos granulares PAS-positivos (LG-PAS; 6,7% de eosinófilos; 0,3% de basófilos e 7,8% de leucócitos imaturos. Variações intraespecíficas foram observadas em todas as características estudadas, podendo ser consideradas como normais, no que tange aos peixes. Não se deve esperar, portanto, que as características biológicas em peixes apresentem- se distribuídas normalmenteHematological characteristics are important tools for diagnosis and prognostic features in fish population and they contribute to the comprehension of comparative physiology, phylogenetic relation, food habit and other ecological parameters. Red blood cell count (RBC, white blood cell count (WBC, thrombocytes counts, glucose, cortisol, hepatosomatic and splenosomatic relation were

  17. Seletividade alimentar de organismos-alimento por formas jovens de pacu Piaractus mesopotamicus (Holmberg, 1887 e curimba Prochilodus lineatus (Valenciennes, 1836 = Selective feeding of food organisms by fish larvae of Piaractus mesopotamicus (Holmberg, 1887 and Prochilodus lineatus (Valenciennes, 1836

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    Nandeyara Ribeiro Marques

    2007-04-01

    Full Text Available Objetivou-se avaliar a seleção alimentar de organismos-alimento por formas jovens de pacu (Piaractus mesopotamicus e curimba (Prochilodus lineatus com diferentes idades (6, 12, 19 e 26 dias, na presença e ausência de Pistia stratiotes. Foram utilizados quatrotratamentos (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba e quatro repetições. A cada sete dias, foram coletadas 24 larvas de cada espécie de peixe dos tanques, sendo estas mantidas em jejum por 24 horas. Depois de distribuídas nos aquários com plâncton, as larvas permaneceram por três horas, sendocoletadas e fixadas para análise, juntamente com as amostras de água. Os tratos digestórios das larvas foram retirados e analisados sob microscópio óptico. Observaram-se diferenças estatísticas na seletividade alimentar de organismos planctônicos por larvas de mesmaespécie, em diferentes idades e também entre larvas de espécies diferentes, com mesma idade, não diferindo quanto à presença ou ausência de P. stratiotes. As formas jovens de pacu e curimba selecionaram organismos similares aos seis dias de idade, passando por alterações até o 26º dia. À medida que se desenvolveram, as larvas de pacu passaram a selecionar cladóceros e ostrácodos e as de curimba, protozoários e algas.Theobjective was to evaluate the feeding selection of food organisms for two species of fish larvae (pacu and curimba at different ages (6, 12, 19 and 26 days after eclosion, in the presence or absence of Pistia stratiotes. Four treatments were used (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba and four replications. Every seven days, 24 fish larvae of each species were collected, and kept without food for 24 hours. Afterbeing distributed in the aquariums with plankton, the larvae stayed for three hours, and were collected and prepared for analysis, along with the water samples. The digestive tract of the fish larvae were

  18. Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases.

    Science.gov (United States)

    de Almeida, Fernanda Losi Alves; Carvalho, Robson Francisco; Pinhal, Danillo; Padovani, Carlos Roberto; Martins, Cesar; Dal Pai-Silva, Maeli

    2008-12-01

    Skeletal muscle is the edible part of the fish. It grows by hypertrophy and hyperplasia, events regulated by differential expression of myogenic regulatory factors (MRFs). The study of muscle growth mechanisms in fish is very important in fish farming development. Pacu (Piaractus mesopotamicus) is one of the most important food species farmed in Brazil and has been extensively used in Brazilian aquaculture programs. The aim of this study was to analyze hyperplasia and hypertrophy and the MRF MyoD expression pattern in skeletal muscle of pacu (P. mesopotamicus) during juvenile and adult growth stages. Juvenile (n=5) and adult (n=5) fish were anaesthetized, sacrificed, and weight (g) and total length (cm) determined. White dorsal region muscle samples were collected and immersed in liquid nitrogen. Transverse sections (10 microm thick) were stained with Haematoxilin-Eosin (HE) for morphological and morphometric analysis. Smallest fiber diameter from 100 muscle fibers per animal was calculated in each growth phase. These fibers were grouped into three classes (50 microm) to evaluate hypertrophy and hyperplasia in white skeletal muscle. MyoD gene expression was determined by semi-quantitative RT-PCR. PCR products were cloned and sequenced. Juvenile and adult pacu skeletal muscle had similar morphology. The large number of fish confirms active hyperplasia. In adult fish, most fibers were over 50 microm diameter and denote more intense muscle fiber hypertrophy. The MyoD mRNA level in juveniles was higher than in adults. A consensus partial sequence for MyoD gene (338 base pairs) was obtained. The Pacu MyoD nucleotide sequence displayed high similarity among several vertebrates, including teleosts. The differential MyoD gene expression observed in pacu white muscle is possibly related to differences in growth patterns during the phases analyzed, with hyperplasia predominant in juveniles and hypertrophy in adult fish. These results should provide a foundation for

  19. Influence of aquatic plants on the predation of Piaractus mesopotamicus larvae by Pantala flavescens - doi: 10.4025/actascibiolsci.v32i2.5167 Influence of aquatic plants on the predation of Piaractus mesopotamicus larvae by Pantala flavescens - doi: 10.4025/actascibiolsci.v32i2.5167

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    Carlos Eduardo Bento Fernandes

    2010-05-01

    Full Text Available The experiment aimed to study the influence of the aquatic plants E. najas, P. stratiotes and S. auriculata on the predation of P. mesopotamicus larvae by P. flavescens. One hundred and twenty larvae of P. mesopotamicus and 24 larvae of P. flavescens were placed in 24 aquariums with capacity of 12 L, with one Odonate per aquarium. Treatments were different regarding the species of aquatic plants E. najas, S. auriculata and P. stratiotes, with one control treatment without aquatic plants. One aquarium (12 L containing one Odonate and 30 P. mesopotamicus larvae was considered one experimental unit. After 18 hours, the Odonates were removed from the aquariums and fish larvae left (alive were counted in each experimental unit. The survival rate of P. mesopotamicus larvae in the treatment without aquatic plants (control was significantly lower than in the treatment with E. najas. However, the survival rates in the aquariums with floating aquatic plants did not differ from the control. The morphological characteristics of E. najas promoted higher structural complexity in the environment, offering more protection to the fish larvae, and increasing their survival. We concluded that the presence of the submerged aquatic plant E. najas promoted the reduction of predation of P. mesopotamicus larvae by Pantala flavescens. Larvae; Piaractus mesopotamicus; Pantala flavescens; predation; aquatic plantsThe experiment aimed to study the influence of the aquatic plants E. najas, P. stratiotes and S. auriculata on the predation of P. mesopotamicus larvae by P. flavescens. One hundred and twenty larvae of P. mesopotamicus and 24 larvae of P. flavescens were placed in 24 aquariums with capacity of 12 L, with one Odonate per aquarium. Treatments were different regarding the species of aquatic plants E. najas, S. auriculata and P. stratiotes, with one control treatment without aquatic plants. One aquarium (12 L containing one Odonate and 30 P. mesopotamicus larvae was

  20. Mercury Levels in Human Hair and Farmed Fish near Artisanal and Small-Scale Gold Mining Communities in the Madre de Dios River Basin, Peru

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    Aubrey L. Langeland

    2017-03-01

    Full Text Available Artisanal and small-scale gold mining (ASGM has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1 examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO Expert Committee of Food Additives (JECFA’s Provisional Tolerable Weekly Intake (PTWI; and (2, to measure the mercury levels of paco (Piaractus brachypomus fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight. We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing geodesic distance from the Madre de Dios headwaters, did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute

  1. Mercury Levels in Human Hair and Farmed Fish near Artisanal and Small-Scale Gold Mining Communities in the Madre de Dios River Basin, Peru.

    Science.gov (United States)

    Langeland, Aubrey L; Hardin, Rebecca D; Neitzel, Richard L

    2017-03-14

    Artisanal and small-scale gold mining (ASGM) has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1) examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO) Expert Committee of Food Additives (JECFA)'s Provisional Tolerable Weekly Intake (PTWI); and (2), to measure the mercury levels of paco ( Piaractus brachypomus ) fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight). We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred) in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing geodesic distance from the Madre de Dios headwaters, did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute to human

  2. Aterações químicas e microbiológicas em PACU (piaractus mesopotamicus armazenado sob refrigeração a 5°c

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    Mauro F.F. Leitão

    1997-08-01

    Full Text Available A pesquisa foi conduzida com o objetivo de analisar a vida útil e o processo de deterioração do pacu (Piaractus mesopotanicus armazenado sob refrigeração em temperatura inadequada (5°C. Amostras do pescado, imediatamente após a captura, foram armazenadas a 5°C e analisadas nos intervalos de 0-7-14 e 21 dias, com relação a características sensoriais e de natureza química (bases nitrogenadas voláteis - BNV, nitrogênio não protéico - NNP, aminoácidos livres totais, histidina livre e histamina e microbiológicos (contagem padrão, produtores de histamina em ágar Niven, contagem de microrganismos gelatinase e H2S positivos, nas temperaturas de 35°C, 20° e 5°C. Os resultados obtidos confirmaram que, a exemplo de outros peixes fluviais de regiões tropicais, o pacu revelou-se bastante resistente ao armazenamento, somente evidenciando uma alteração marcante após 14 dias de estocagem. Assim mesmo, a rejeição do pescado foi baseada principalmente em características sensoriais (odor, aspecto, textura uma vez que com relação aos índices químicos (BNV e mesmo microbiológicos, não se caracterizava uma situação definitiva de deterioração e rejeição. Observou-se, também, que o processo de deterioração pareceu concentrar-se principalmente no muco superficial, sendo que as características químicas do tecido muscular não evidenciaram alterações marcantes, mesmo após 21 dias de armazenamento. A presença de histamina não foi positivada nas amostras e os níveis de histidina livre, embora relativamente elevadas, não sugerem maiores riscos desta espécie de peixe como eventual veículo de intoxicação por histamina. No entanto, bactérias his+ foram isoladas das amostras iniciais, entre elas cepas de Plesiomonas shigelloides e Vibrio fluvialis. A microbiota contaminante natural foi reduzida, predominando microrganismos mesófilos/psicrotrófilos, com baixas contagens iniciais a 5°C. Ao longo do armazenamento a 5

  3. Perulernaea gamitanae (Copepoda: Lernaeidae parasitizing tambaqui (Colossoma macropomum (Characidae and the hybrids tambacu and tambatinga, cultured in northern Brazil

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    M. Tavares-Dias

    2011-08-01

    Full Text Available The infestation rate in Colossoma macropomum, hybrid tambacu (C. macropomum x Piaractus mesopotamicus and hybrid tambatinga (C. macropomum x Piaractus brachypomum with Perulernaea gamitanae Thatcher and Paredes, 1985 from two fish farms in Amapá State, Brazil was studied. Lernaeid parasites (n=2887 were collected mainly on the tongue and the mouth cavity and also on cartilage of gill arches and filaments. Inflammation and fibrous nodules were observed on the attachment sites of the parasites. The infestation rate varied according to the fish farm and host. The prevalence of P. gamitanae was of 100% in hosts from one fish farm and was lower in the other fish farm. Higher intensity of P. gamitanae occurred in hybrids tambacu and tambatinga, but despite the high prevalence its intensity was moderate. This is the first report on epidemiology of P. gamitanae in cultured fishes from Brazilian Amazonia, and the occurrence of this crustacean parasite in two new hosts, the hybrids tambacu and tambatinga.

  4. Histologia e ultraestrutura do rim e rim cefálico do pacu

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    Gerlane M. Costa

    2012-05-01

    Full Text Available O pacu, Piaractus mesopotamicus, é um teleósteo da Família Characidae, intensivamente cultivado no Brasil devido sua rusticidade, crescimento rápido e fácil adaptação. O conhecimento morfológico dos sistemas corpóreos, incluído órgãos linfóide, se faz necessário, para uma melhor produção no cultivo de peixes, fornecendo subsídios na manutenção dos estoques. O objetivo deste estudo foi descrever morfologicamente o rim e rim cefálico de Piaractus mesopotamicus, analisando os perfis celulares de cada órgão com o uso de microscopia de luz e microscopia eletrônica de transmissão. O resultado da análise macroscópica mostrou que a localização do rim e rim cefálico são as mesmas encontradas na maioria dos teleósteos. O rim apresentou uma forma em "H", onde a região média se expandia sobre a bexiga natatória. O rim cefálico se apresentou como uma dilatação na região cranial do rim, mostrando-se bem visível. Na microscopia eletrônica de transmissão também foram observadas similaridades ultraestruturais com outros teleósteos. Observando nossos resultados concluímos que histologicamente e ultraestruturalmente, os órgãos linfóides rim e rim cefálico de Piaractus mesopotamicus são similares aos de outros teleósteos.

  5. Gonadossomatic relation and reproductive strategy of Brycon opalinus (Cuvier, 1819 in the Serra do Mar State Park - Núcleo Santa Virgínia, Atlantic Forest, Brazil

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    LM Gomiero

    Full Text Available The objective of this study was to analyze the gonadossomatic relation of males and females of Brycon opalinus (the Pirapitinga do Sul in the Serra do Mar State Park-Núcleo Santa Virgínia. The study area included three rivers: Paraibuna, Ipiranga, and Grande. From the gonadossomatic relation, it was possible to determine the reproductive season and strategy of this species. The gonadossomatic relation was high throughout the year for both males and females. Sperm competition and dilution of the ejaculate in the spawning locations favored substantial development of the testicles. The sex ratio of Brycon opalinus was always in favor of females. The existence of sexual dimorphism in this species was confirmed from the larger size of the females.

  6. New host records and description of the egg of Anacanthorus penilabiatus (Monogenea, Dactylogyridae

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    MC Pamplona-Basilio

    2001-07-01

    Full Text Available Anacanthorus penilabiatus is referred parasitizing the type-host Piaractus mesopotamicus (Serrasalmidae and two new hosts, Colossoma macropomum and C. brachypomum (Characidae from fish ponds of "Departamento Nacional de Obras Contra as Secas", Pentecoste, State of Ceará, Brazil. Table of measurements and the first description of the egg are presented.

  7. Seletividade alimentar de organismos-alimento por formas jovens de pacu Piaractus mesopotamicus (Holmberg, 1887 e curimba Prochilodus lineatus (Valenciennes, 1836 - DOI: 10.4025/actascibiolsci.v29i2.523 Selective feeding of food organisms by fish larvae of Piaractus mesopotamicus (Holmberg, 1887 and Prochilodus lineatus (Valenciennes, 1836 - DOI: 10.4025/actascibiolsci.v29i2.523

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    Carlos Eduardo Bento Fernandes

    2007-12-01

    Full Text Available Objetivou-se avaliar a seleção alimentar de organismos-alimento por formas jovens de pacu (Piaractus mesopotamicus e curimba (Prochilodus lineatus com diferentes idades (6, 12, 19 e 26 dias, na presença e ausência de Pistia stratiotes. Foram utilizados quatro tratamentos (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba e quatro repetições. A cada sete dias, foram coletadas 24 larvas de cada espécie de peixe dos tanques, sendo estas mantidas em jejum por 24 horas. Depois de distribuídas nos aquários com plâncton, as larvas permaneceram por três horas, sendo coletadas e fixadas para análise, juntamente com as amostras de água. Os tratos digestórios das larvas foram retirados e analisados sob microscópio óptico. Observaram-se diferenças estatísticas na seletividade alimentar de organismos planctônicos por larvas de mesma espécie, em diferentes idades e também entre larvas de espécies diferentes, com mesma idade, não diferindo quanto à presença ou ausência de P. stratiotes. As formas jovens de pacu e curimba selecionaram organismos similares aos seis dias de idade, passando por alterações até o 26º dia. À medida que se desenvolveram, as larvas de pacu passaram a selecionar cladóceros e ostrácodos e as de curimba, protozoários e algas.The objective was to evaluate the feeding selection of food organisms for two species of fish larvae (pacu and curimba at different ages (6, 12, 19 and 26 days after eclosion, in the presence or absence of Pistia stratiotes. Four treatments were used (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba and four replications. Every seven days, 24 fish larvae of each species were collected, and kept without food for 24 hours. After being distributed in the aquariums with plankton, the larvae stayed for three hours, and were collected and prepared for analysis, along with the water samples. The digestive tract of the fish larvae

  8. Método estimativo para amostragem quantitativa de Rondonia rondoni (Nematoda: Atractidae parasito de peixes Estimative method for quantitative sampling of Rondonia rondoni (Nematoda: Atractidae parasite of fish

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    Cristiane M. De Campos

    2007-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o número de Rondonia rondoni no intestino de Piaractus mesopotamicus, por meio da diferença entre peso úmido e peso seco das amostras de parasitos para cada hospedeiro, a partir da relação do peso seco e número de parasitos pré-estabelecida. Amostras totais de R. rondoni, de 37 espécimes de Piaractus mesopotamicus, foram medidas para obtenção do peso úmido, desidratadas em estufa com temperatura entre 55ºC e 60ºC e, após 24 h seu peso seco foi determinado. Por meio de uma regra de três simples, calculou-se o número de parasitos a partir da diferença entre o peso úmido e o peso seco, considerando um erro padrão médio de 6,027 para um número médio de 1010 indivíduos, quantificado em ensaio prévio. A equação da regressão linear estimada foi de y = 13,138x - 162,01 e r² = 0,9989, a qual foi significativa (p The presente work evaluated the number of Rondonia rondoni in intestine of Piaractus mesopotamicus, for diference of dry and wet weight of parasites samples by each host, from the relation dry weight and number of parasites. Totals samples of R. rondoni of 37 specimens of P. mesopotamicus for attaiment of wet weight, dehydrated in stove with temperature between 55ºC and 60ºC, the wet weight was measured after 24 h. The number of parasites was calculated with rule of three, considering the average number of 1,010 ± 6.027 specimens quantified in previous assay. The equation of linear regression is y = 13.138x - 162.01 and r² = 0.9989. The normality of the data was proven with Kolmogorov-Smirnov (p < 0.01.

  9. Cooking process evaluation on mercury content in fish Influência do processo de cocção no teor de mercúrio em peixes

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    Luciana Aparecida Farias

    2010-12-01

    Full Text Available This study evaluated different cooking processes (roasted, cooked and fried on total mercury (Hg content in fish species most consumed by Manaus residents and surrounding communities, Amazon region. The results obtained for total Hg in natura and after the three types of preparation (roasted, cooked and fried for 12 fish species showed a significant Hg concentration variation. In the present study the cooked and frying processes resulted in higher Hg losses for Pacu, Pescada, Jaraqui, Curimatã, Surubin and Aruanã fish species, most of them presenting detritivorous and carnivorous feeding habits. The higher Hg losses in the roasting process occurred for Sardinha, Aracu, Tucunaré, Pirapitinga, Branquinha and Tambaqui fish species, most of them being omnivorous and herbivorous fish species. Some micronutrients (Ca, Fe, K, Na, Se and Zn in fish species in natura were also determined in order to perform a nutritional evaluation regarding these micronutrients.O presente estudo avaliou três diferentes processos de cocção (assado, cozido e frito e sua relação com o teor de mercúrio total (Hg em espécies de peixes comumente consumidas pela população de Manaus e comunidades vizinhas da região Amazônica. Os resultados obtidos para Hg total in natura (antes e após os três tipos de preparo (assado, cozido e frito para as 12 espécies de peixes selecionadas apresentaram uma significativa variação na concentração. Os processos de cozimento e fritura resultaram em maiores perdas de Hg para as espécies Pacu, Pescada, Jaraqui, Curimatã, Surubin e Aruanã sendo a maioria delas classificadas como espécies detritívoras e carnívoras. As maiores perdas de Hg no processo assado ocorreram para as espécies Sardinha, Aracu, Tucunaré, Pirapitinga, Branquinha e Tambaqui, a maioria classificadas como espécies omnivoras e herbivoras. Alguns micronutrientes (Ca, Fe, K, Na, Se e Zn nas espécies de peixes in natura foram determinados com o objetivo

  10. Estimulantes alimentares para larvas de pacu Feeding stimulants for pacu lavae

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    Marcelo Borges Tesser

    2011-09-01

    Full Text Available Este estudo foi realizado com o objetivo de investigar o efeito estimulante de cinco aminoácidos (alanina, arginina, glicina, histidina e lisina da betaína e de suas misturas sobre a taxa de ingestão de dieta microencapsulada durante o desenvolvimento larval de pacu Piaractus mesopotamicus. Os resultados da análise estatística comprovaram a existência de efeito significativo, tanto da idade das larvas como dos aminoácidos, sobre a taxa de ingestão. No entanto, não houve significância estatística para a interação dos dois fatores. A glicina, a lisina e a beta��na foram considerados bons estimuladores do comportamento alimentar de larvas de pacu.The present study aimed to investigate the stimulant effect of five amino acids (alanine, arginine, glycine, histidine and lysine from betaine and their mixtures on the ingestion rates of formulated diet during the larval development of pacu Piaractus mesopotamicus. The statistical results showed significant effect of age and treatment. However, no significant effect was observed for the interaction of both factors. Glycine, lysine and betaine are considered good stimulants of the pacu feeding behavior.

  11. Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002 from four tropical fish species in Brazil

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    F. Pilarski

    Full Text Available Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus, pacu (Piaractus mesopotamicus, tambaqui (Colossoma macropomum and cascudo (Hypostomus plecostomus were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968 artificial culture medium (broth and solid which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility, contained a large number of long slender bacteria and gathered into ‘columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

  12. Evaluation of methods to estimate the essential amino acids requirements of fish from the muscle amino acid profile

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    Álvaro José de Almeida Bicudo

    2014-03-01

    Full Text Available Many methods to estimate amino acid requirement based on amino acid profile of fish have been proposed. This study evaluates the methodology proposed by Meyer & Fracalossi (2005 and by Tacon (1989 to estimate amino acids requirement of fish, which do exempt knowledge on previous nutritional requirement of reference amino acid. Data on amino acid requirement of pacu, Piaractus mesopotamicus, were used to validate de accuracy of those methods. Meyer & Fracalossi's and Tacon's methodology estimated the lysine requirement of pacu, respectively, at 13 and 23% above requirement determined using dose-response method. The values estimated by both methods lie within the range of requirements determined for other omnivorous fish species, the Meyer & Fracalossi (2005 method showing better accuracy.

  13. Disease resistance of pacu Piaractus mesopotamicus (Holmberg, 1887 fed with β-glucan

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    JD Biller-Takahashi

    Full Text Available Effects of β-glucan on innate immune responses and survival were studied in pacu experimentally infected with Aeromonas hydrophila. Fish fed diets containing 0, 0.1% and 1% β-glucan were injected with A. hydrophila. β-glucan enhanced fish survival in both treated groups (26.7% and 21.2% of the control, respectively. Leukocyte respiratory burst and alternative complement pathway activities were elevated after bacterial challenge regardless the β-glucan concentration. Lysozyme activity was higher after infection and showed a gradual increase as β-glucan concentration increased. A significant elevation in WBC count was observed either after bacterial challenge or by influence of β-glucan separately. The same response was observed in the number of thrombocytes, lymphocytes, eosinophils, LG-PAS positive cell and monocytes. It can be concluded that feeding pacu with β-glucan can increase protection against A. hydrophila, due to changes in non-specific immune responses.

  14. Expression of cellular components in granulomatous inflammatory response in Piaractus mesopotamicus model.

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    Wilson Gómez Manrique

    Full Text Available The present study aimed to describe and characterize the cellular components during the evolution of chronic granulomatous inflammation in the teleost fish pacus (P. mesopotamicus induced by Bacillus Calmette-Guerin (BCG, using S-100, iNOS and cytokeratin antibodies. 50 fish (120±5.0 g were anesthetized and 45 inoculated with 20 μL (40 mg/mL (2.0 x 10(6 CFU/mg and five inoculated with saline (0,65% into muscle tissue in the laterodorsal region. To evaluate the inflammatory process, nine fish inoculated with BCG and one control were sampled in five periods: 3rd, 7th, 14th, 21st and 33rd days post-inoculation (DPI. Immunohistochemical examination showed that the marking with anti-S-100 protein and anti-iNOS antibodies was weak, with a diffuse pattern, between the third and seventh DPI. From the 14th to the 33rd day, the marking became stronger and marked the cytoplasm of the macrophages. Positivity for cytokeratin was initially observed in the 14th DPI, and the stronger immunostaining in the 33rd day, period in which the epithelioid cells were more evident and the granuloma was fully formed. Also after the 14th day, a certain degree of cellular organization was observed, due to the arrangement of the macrophages around the inoculated material, with little evidence of edema. The arrangement of the macrophages around the inoculum, the fibroblasts, the lymphocytes and, in most cases, the presence of melanomacrophages formed the granuloma and kept the inoculum isolated in the 33rd DPI. The present study suggested that the granulomatous experimental model using teleost fish P. mesopotamicus presented a similar response to those observed in mammals, confirming its importance for studies of chronic inflammatory reaction.

  15. Short-term cold storage of sperm from six neotropical characiformes fishes

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    Simone Marques

    2004-09-01

    Full Text Available Sperm of the following Neotropical Characiformes fish species were tested for cold storage: Brycon lundii, Piaractus mesopotamicus, Leporinus elongatus, Leporinus friderici, Prochilodus lineatus and Prochilodus marggravii. Each sperm sample was split into two aliquots. The first was placed into a plastic bag with air or oxygen and the second, in a plastic tube with air. The samples were maintained at temperatures between 1.7-4.9 ºC. The rate of sperm motility was estimated using a 50 mM NaCl solution as the activating solution. The shortest sperm storage duration (7 h was recorded for L. friderici, when the sperm motility rate reached ~ 30%, whereas the longest duration (20 h was obtained with the sperm of P. lineatus. A fertilisation test using Prochilodus marggravii sperm refrigerated for 8 h yielded 88-90% of viable embryos. The refrigerated storage method could be of practical applications, especially in fish reproductive management at hatchery stations.O sêmen das seguintes espécies de Characiformes neotropicais foi testado para armazenamento em ambiente resfriado: Brycon lundii, Piaractus mesopotamicus, Leporinus elongatus, Leporinus friderici, Prochilodus lineatus e Prochilodus marggravii. Amostras de sêmen, obtidas por massagem da parede celômica, foram armazenadas em saco plástico com ar ou oxigênio ou em tubo plástico com ar, e mantidas resfriadas entre 1,7-4,9º C. A taxa de motilidade espermática foi estimada usando-se NaCl 50 mM como solução ativadora. O sêmen com menor duração de viabilidade (7 h foi o de L. friderici, quando a taxa de motilidade espermática alcançou ~30%, enquanto que o de maior duração (20 h foi o de P. lineatus. A fertilização de ovócitos utilizando sêmen refrigerado por 8 h de Prochilodus marggravii produziu 88-90% de embriões viáveis. O método de armazenamento desenvolvido neste trabalho tem aplicações práticas, especialmente no manejo reprodutivo de peixes em estações de

  16. Crescimento de juvenis de pacu em tanques com aeração noturna - DOI: 10.4025/actascianimsci.v25i1.2122 Growth of pacu juveniles in nightly aerated system - DOI: 10.4025/actascianimsci.v25i1.2122

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    Evoy Zaniboni Filho

    2003-04-01

    Full Text Available O presente estudo avalia o efeito de duas densidades de estocagem (20 e 40 peixes/m2 e da aeração noturna da água dos tanques de cultivo do pacu Piaractus mesopotamicus (Holmberg, 1887. Um total de 12 tanques com fundo de terra e paredes de alvenaria foram utilizados em 4 tratamentos com 3 repetições cada. Foram utilizados alevinos com 30 dias de idade, pesando em média 1,93 ± 1,70g, e o experimento foi conduzido durante 60 dias. A aeração noturna possibilitou a obtenção de valores médios de oxigênio de 5,6 ± 0,5 e 5,8 ± 0,5mg O2/l para as densidades de 20 e 40 peixes/m2, enquanto nos tanques sem a aeração os valores de oxigênio foram de 4,3 ± 0,7 e 3,4 ± 0,7mg O2/l, respectivamente. A biomassa foi o único parâmetro que aumentou com a aeração noturna, enquanto que a sobrevivência e o crescimento apresentaram efeitos discretos.The present study evaluated the effects of two stocking densities (20 and 40 fish/m2 and nightly aeration on water quality and growth of pacu, Piaractus mesopotamicus (Holmberg, 1887. Twelve ponds with concrete walls and earthen bottom were used to set 4 treatments with 3 repetitions each. 30-day old fish with average weight (mean standard ± deviation of 1.93 ± 1.70g in the beginning of the experiment were observed for 60 days. Nightly aeration promoted 5.6 ± 0.5 and 5.8 ± 0.5mg O2/l at dawn in the population densities of 20 and 40 fish/m2, while the unaerated ponds allowed 4.3 ± 0.7 and 3.4 ± 0.7mg O2/l for these densities, respectively. Fish biomass was the only biological parameter increased by nightly aeration, while discrete effects were observed in growth and survival.

  17. Fauna parasitária de peixes oriundos de “pesque-pague” do município de Guariba, São Paulo, Brasil - DOI: 10.4025/actascibiolsci.v28i3.253 Parasitic fauna of cultivated fishes in fee fishing farm of Guariba, São Paulo State, Brazil - DOI: 10.4025/actascibiolsci.v28i3.253

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    Julieta Rodini Engracia de Moraes

    2007-11-01

    Full Text Available Este trabalho descreve a ocorrência e a sazonalidade de parasitos em peixes de “pesque-pague” do município de Guariba, Estado de São Paulo, Brasil (21º15`22``S, 48º18`58``W e 595 m de altitude, durante o período de agosto de 2001 a julho de 2002. A presença de parasitos foi pesquisada em pacu Piaractus mesopotamicus (Characidae, carpa comum Cyprinus carpio (Cyprinidae, tilápia-do-Nilo Oreochromis niloticus (Cichlidae, híbrido tambacu (macho de P. mesopotamicus x fêmea de tambaqui-Colossoma macropomum e piraputanga Brycon hillari (Characidae. Os resultados demonstram que dos 100 peixes examinados, 15% estavam parasitados por pelo menos um dos seguintes parasitos: Trichodina sp.; helmintos monogenóides; copepoditos de Lernaea cyprinacea; L. cyprinacea adulta ou Dolops carvalhoi. Por ordem decrescente, o grau de suscetibilidade dos hospedeiros foi C. carpio, P. mesopotamicus, B. hillari, híbrido tambacu e O. niloticus. Por ordem decrescente, os parasitos encontrados foram helmintos monogenóides, Dolops carvalhoi, Trichodina sp., Lernaea cyprinacea adultas e suas formas jovens.This study describes the occurrence and the seasonality of parasites of cultivated fish from a fee fishing farm located in Guariba, São Paulo State, Brazil (21º15`22`` S, 48º18`58`` W and 595 m of altitude, from August, 2001 to July, 2002. The presence of parasites was researched in pacu Piaractus mesopotamicus (Characidae, common carp Cyprinus carpio (Cyprinidae, nile-tilapia Oreochromis niloticus (Cichlidae, tambacu hybrid (male of P. mesopotamicus x female of tambaqui-Colossoma macropomum and piraputanga Brycon hillari (Characidae. Results demonstrate that out of 100 fish examined, 15% were sponged for at least one of the following parasites: Trichodina sp.; monogenean helminths; copepodits of Lernaea cyprinacea; adults of L. cyprinacea; or Dolops carvalhoi. In decreasing order, the susceptibility degree of the hosts was C. carpio, P. mesopotamicus, B

  18. Variação temporal e espacial de ovos e de larvas das espécies de interesse para a pesca na sub-bacia do rio Miranda, Pantanal, Estado do Mato Grosso do Sul, Brasil - DOI: 10.4025/actascibiolsci.v27i3.1314 Temporal and spatial variation of fish eggs and larvae of the main exploited species in the sub-basin of Miranda River, Pantanal wetland, State of Mato Grosso do Sul, Brazil - DOI: 10.4025/actascibiolsci.v27i3.1314

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    Keshyiu Nakatani

    2005-03-01

    Full Text Available Foi analisada a variação temporal de ovos e de larvas das principais espécies exploradas no Pantanal: Piaractus mesopotamicus; Prochilodus lineatus; Salminus maxillosus; Leporinus macrocephalus e Pseudoplatystoma spp., no rio Miranda. As coletas foram realizadas nos meses de outubro a março, quinzenalmente, de 1996 a 1999. O rio foi dividido em trecho superior, médio e inferior, com 15 pontos de coleta. Foram utilizadas rede de plâncton cônico-cilindrica, com fluxômetro, e as amostras fixadas em formol 4%. Para a identificação, utilizaram-se características morfológicas e merísticas, grau de flexão da notocorda e elementos da nadadeira caudal. No primeiro período, foram capturadas 5.979 larvas e 1.075 ovos; no segundo, 108.912 larvas e 1.836 ovos; no terceiro, 13.465 larvas e 1.855 ovos. A ANOVA, entre os anos e trechos do rio, foi significativa (F= 6.5, p >0,05 no trecho médio, indicando que a reprodução ocorre do trecho médio para o superior, nos meses de novembro a janeiroThe aim of this study was to analyze temporal variation of fish eggs and larvae of the main exploited species in Miranda river, Pantanal wetland (Piaractus mesopotamicus, Prochilodus lineatus, Salminus maxillosus, Leporinus macrocephalus, and Pseudoplatystoma spp., which were collected from October to March, biweekly, from 1996 to 1999. The river was divided into superior, medium and inferior sections, of 15 collection sites. Conical-cylindrical plankton net with a fluxometer and samples fixed in formol 4% were utilized. Morphological and meristic characteristics, notochord flexion degree and caudal fin elements were utilized for identification. A total of 5,979 larvae and 1,075 eggs were collected in the first period; 108,912 larvae and 1,836 eggs in the second; 13,465 larvae and 1,855 eggs in the third. Results showed that ANOVA, between the years and the river stretches, was significant (F = 6.5, p >0.05 in the medium section, which indicates that the

  19. Caracterização do uso de malhadeiras pela frota pesqueira que desembarca em Manaus e Manacapuru, Amazonas Characterization of gillnet fisheries landed in Manaus and Manacapuru, Central Amazon

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    Valdelira Lia Araújo Fernandes

    2009-01-01

    Full Text Available A malhadeira é um apetrecho de pesca frequentemente utilizado na pesca regional. O presente estudo visa verificar características das malhadeiras utilizadas nos diversos subsistemas da Amazônia Central, seu uso e a aplicação de normas legais relacionadas. Os dados foram obtidos por meio de entrevistas com pescadores em Manaus entre 1994 e 2004 e em Manacapuru entre 2001 e 2004. Os resultados indicaram que o apetrecho responde em média a 14% da produção pesqueira de Manaus, com tendência a diminuição e a 24,5% de Manacapuru, com estabilidade interanual. As freqüências modais recentes do tamanho de malha estiveram entre 50-60 mm no desembarque em Manaus, mas em Manacapuru foram mais diversas, entre 20 mm e 90 mm. A moda do comprimento das redes foi de 100 m em ambos portos, mas se em Manaus correspondem a cerca de 90% das registradas, em Manacapuru não são nem 50% do total. Quanto à freqüência de ocorrência de uso da malhadeira nos subsistemas da Amazônia Central que desembarcaram em Manaus, destaca-se o rio Purus (47,8%, enquanto que para Manacapuru predominou explotação no Baixo Solimões (94,3%. A composição das capturas variou entre os anos analisados, destacando cinco principais pescados que compõem mais de 70% das capturas: tambaqui, aruanã, tucunaré, curimatá, pirapitinga. Com relação às restrições no tamanho de malha, a maioria dos apetrechos têm tamanho de malha passível de uso ilegal, similarmente aos comprimentos das mesmas. Concluiu-se que há grande diversidade de formas de uso do apetrecho, sendo necessário gerar normas legais mais efetivas e compatíveis com a realidade pesqueira, cultural e sócio-econômica da Amazônia.The gillnet is frequently used in Amazon commercial and artisanal fishing. The present study aims to verify characteristics of the gill-nets of gillnets found in various Central Amazon subsystems, their use, and compliance with related legal norms. Daily Interviews were made from

  20. Digestible energy of crude glycerol for pacu and silver catfish

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    Rafael Ernesto Balen

    2014-01-01

    Full Text Available The increase in global biodiesel production is originating a glycerol surplus, which has no defined destination. An alternative to overcome this problem is its use as energy source in animal feeding. In Brazil, Pacu (Piaractus mesopotamicus is one of the most farmed native fish species, whereas Silver catfish (Rhamdia quelen is suitable for production in subtropical region. Considering little knowledge about crude glycerol utilization in feeds for Neotropical fish species, it was evaluated the apparent digestibility coefficients (ADCs for energy of crude glycerol for P. mesopotamicus and R. quelen. The digestibility and digestible energy content of crude glycerol can be considered excellent even when compared to energy of common ingredients such as maize and wheat, presenting 0.97 and 0.89 of energy ADCs, and 15.2 and 13.95MJ kg-1 of digestible energy for Pacu and Silver catfish, respectively. In conclusion, crude glycerol is an energetic ingredient with good potential in Brazilian native fish diets.

  1. Leukocytes respiratory burst activity as indicator of innate immunity of pacu Piaractus mesopotamicus

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    JD Biller-Takahashi

    Full Text Available The present study evaluated the assay to quantify the respiratory burst activity of blood leukocytes of pacu as an indicator of the innate immune system, using the reduction of nitroblue tetrazolium (NBT to formazan as a measure of the production of reactive oxygen species (ROS. In order to assess the accuracy of the assay, fish were challenged by Aeromonas hydrophila and sampled one week after challenge. The A. hydrophila infection increased the leukocyte respiratory burst activity. The protocol showed a reliable and easy assay, appropriate to determine the respiratory burst activity of blood leukocytes of pacu, a neotropical fish, in the present experimental conditions.

  2. Stress responses in juvenile pacu (Piaractus mesopotamicus submitted to repeated air exposure = Respostas de estresse em juvenis de pacu (Piaractus mesopotamicus submetidos à exposição aérea repetitiva

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    Jaqueline Dalbello Biller

    2008-01-01

    Full Text Available Pacu juveniles (5.2 ± 1.5 g were submitted to two one-minute air exposures in a 24h interval, and sampled before the exposure (control and 5, 15, 30 and 60 min., 24 and 48h afterwards for whole-body cortisol, sodium, potassium and calcium ion concentrations. For the first air exposure, there was a trend of increased cortisol concentration after 15 min., whereas in the second air exposure, the cortisol concentration increased significantly within 5 min. after stress was induced. Sodium ion concentrationincreased significantly 24h after both air exposures. Potassium concentration presented fluctuations over the experimental period. Calcium ion concentration increased progressively from 5 to 30 min., in both air exposures. The repeated air exposures exacerbated the cortisol response, but they did not affect the recovery ability of pacu over the experimental period. Additionally, the whole-body cortisol measurement might be a reliable indicator of stress, when sampled fish are smaller and blood volumes are very low, making samples inadequate for analysis.Juvenis de pacu (5,2 ± 1,5 g foram submetidos a duas exposições aéreas de um minuto, em intervalo de 24 horas, e amostradosantes da exposição (controle e 5, 15, 30 e 60 min., 24 e 48 horas depois para análise da concentração corporal de cortisol e dos íons sódio, potássio e cálcio. Na primeira exposição, os peixes apresentaram concentrações de cortisol aumentadas a partir de 15 min., embora não diferissem estatisticamente do controle. Na segunda exposição, a concentração de cortisol aumentou significativamente aos 5 min., retornando às concentrações equivalentes às dos peixes-controle em 30 min.. A concentração do íon sódio aumentousignificativamente 24 horas depois das duas exposições aéreas. A concentração do íon potássio apresentou flutuações durante o experimento, enquanto a do cálcio apresentou-se reduzida aos 5 min, aumentando gradativamente até os 30 min., nas duas exposições. Arepetição do fenômeno estressor exacerbou a liberação de cortisol, mas não afetou a capacidade de recuperação dos peixes. A análise do cortisol tecidual pode ser considerada um indicador confiável de estresse.

  3. PHYSIOLOGICAL RESPONSES OF PACU (Piaractus mesopotamicus, FED CASSAVA (Manihot esculenta FOLIAGE IN DIETS RESPOSTAS FISIOLÓGICAS DO PACU (Piaractus mesopotamicus, ALIMENTADO COM RAMA DE MANDIOCA (Manihot esculenta NA RAÇÃO

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    João Teodoro Padua

    2009-07-01

    Full Text Available Brazil is the largest world producer of cassava. Leafs and stem of cassava can be a alternative source of protein for omnivorous fish. However, the potential use is limited by the presence of high level of cyanide acid. The present study evaluated physiological responses of juvenile pacu submitted to increasing levels of the final third of the cassava foliage meal in diets. A completely randomized design was used in factorial scheme 4x2, four levels, 0, 12, 24 and 36 % of cassava foliage meal (CFM, and 2 levels of crude protein (CP, 24 % and 30 %, with three replicates. Three hundred twelve fish (55.33±6.19 g were distributed into 24 ponds of 13 m2. Results indicated that the levels of CFM inclusion affected the hemoglobin values (P<0.01, as well as the CP level (P<0.05, with interaction of these factors (P<0.01. Significant interaction among the CFM levels and CP was also observed for hematocrit, plasma protein (P<0.01 and plasma lipid (P<0.05. In the 24 % CP level was observed higher values of Hb in control and 36 % of CFM (3.51 g/dl and 3.25 g/dl respectively while with 30 % CP the control diet and 36 % CFM presented the smallest values (3.29 g/dl and 2.78 g/dl respectively. The higher level of CFM tested, inside of any protein level, had low influence on the pacu metabolism.

    KEY WORDS: Cassava leaf and stem fish metabolism, pacu, P. Mesopotamicus.
    O Brasil é o maior produtor mundial de mandioca, disponibilizando a rama de mandioca como fonte alternativa na alimentação de peixes onívoros. No entanto, o potencial de uso da rama é limitado pela toxidez do ácido cianídrico. Objetivou-se avaliar a resposta fisiológica do pacu alimentado com níveis crescentes da rama de mandioca. Utilizou-se delineamento inteiramente casualizado, em fatorial 4x2, quatro níveis de rama de mandioca (RM (0%, 12%, 24% e 36% e dois níveis de proteína bruta (PB (24% e 30% com três repetições. Trezentos e doze peixes (55,33±6,19 g foram distribuídos em 24 viveiros de 13 m2 cada. A RM influenciou a taxa de hemoglobina (P<0,01. Ocorreu interação entre RM e PB para as variáveis hemoglobina, hematócrito, proteína plasmática (P<0,01 e lipídio plasmático (P<0,05. Com 24% de PB foi observado maior valor de Hb nos tratamentos controle (3,51 g/dl e 36 % de RM (3,25 g/dl, enquanto que, com 30 % de PB, os tratamentos controle e 36 % de RM apresentaram os menores valores, 3,29 g/dl e 2,78 g/dl, respectivamente. Comportamento semelhante foi observado no Ht. As alterações metabólicas observadas evidenciaram que a utilização de até 36% do terço final da RM processado é uma alternativa na alimentação do pacu em crescimento.

    PALAVRAS-CHAVES: Metabolismo de peixe, pacu, P. mesopotamicus, rama de mandioca.

  4. Diâmetro do ingrediente e a digestibilidade aparente de rações por duas espécies de peixes tropicais Ingredient diameter and apparent digestibility of diet by two tropical fish species

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    Margarida Maria Barros

    2002-04-01

    Full Text Available Este estudo foi realizado no Laboratório de Pesquisas em Nutrição de Organismos Aquáticos, da FMVZ - Unesp Campus de Botucatu, Estado de São Paulo, unidade integrada ao Centro de Aquicultura da Unesp. Teve por objetivo avaliar a influência do diâmetro do ingrediente alimentar (0,5; 1,0; 1,5; 2,0 e 2,5 mm, por meio da digestibilidade aparente de rações pela tilápia do Nilo, Oreochromis niloticus L. (Perciformes cichlidae, e pelo pacu, Piaractus mesopotamicus (Holmberg Characiformes, Characidae, com peso médio de 100,0 gramas. Foram determinados os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e extrato etéreo. Estes tratamentos foram avaliados por meio de análise de variância em um esquema fatorial 2 x 5 (duas espécies de peixes e cinco diâmetros. Os resultados demonstram que existe interação significativa entre o diâmetro da partícula alimentar e a espécie, e que o diâmetro mais adequado da partícula para a confecção de rações apresenta-se entre 1,0 mm e 2,0 mm para o pacu e, de 1,5 mm para a tilápia do Nilo.This research was carried out at the Aquatic Organisms Nutrition Research Laboratory, FMVZ - Unesp - Campus of Botucatu, a unit of Aquaculture Center of Unesp (Universidade Estadual de São Paulo - Brazil. The objective was to evaluate the ingredient diameter influence (0.5; 1.0; 1.5; 2.0 and 2.5 mm, using the apparent digestibility of diets by Nile tilapia, Oreochromis niloticus L. (Perciformes cichlidae and pacu, Piaractus mesopotamicus (Holmberg Characiformes, Characidae. The coefficients were determined according to dry matter, crude protein and ether extract. These treatments were analyzed by variance analysis in the factorial design 2 x 5 (two fish species and five diameters. The result showed that there is significant interaction between ingredient diamater and species and that, the most appropriate ingredient diameter to manufacture fish diets is between 1.0 and 2.0 mm to pacu

  5. Eficácia do fembendazole no controle de nematódeos de pacu Piaractus mesopotamicus (Holmberg, 1987 The efficiency of fembendazole in the control of nematodes in pacu Piaractus mesopotamicus (Holmberg, 1987

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    Jorge Erick Garcia Parra

    1997-06-01

    Full Text Available O presente trabalho foi realizado no Centro de Pesquisa e Treinamento em Aquicultura (CEPTA/1BAMA, município de Pirassununga, SP. Foram utilizados 60 pacus, dos viveiros da Estação de Piscicultura do CEPTA, com peso médio de 600g. Foi realizado um teste visando avaliar o efeito do Femben-dazote (adicionado no alimento em diferentes dosagens, sobre os nematódeos presentes no tubo intestinal do pacu, utilizando três tratamentos: Tl - grupo testemunha (ração sem Fembendazole, T2 - 20mg de Fembendazole/kg de ração e T3 - 40mg de Fembendazo-le/kg de ração. O delineamento foi inteiramente casualizado. A unidade experimental foi o peixe. Não houve diferença significativa (P 0,05 entre os tratamentos com anti-helmintico Fembendazole nas dosagens de 20mg/kg e 40/ng/kg de ração e o grupo testemunha.This study was done at lhe Agricultural Centre for Training and Research (CEPTA/IBAMA m the municipality of Pirassununga, São Paulo. Sixty pacus, wilh an average weight of 600g were obtained from the nurseries of the fish statíon at CEPTA. An experiment to determine the ejfect of fenbendazole (added to the ration in varíous doses on nematodes in the alimentary canal ofthe pacu was realized using three treatments. Tl - contrai group (ration without fenbendazole, T2 - 20mg fenbendazole/kg ration, and T3 - 40mgfenbendazole/kg ration. The experimental ouüine was totally random. The fish was the experimental unit. There was no significam dijference (P 0.05 befween the treatments wilh the anti-helminthic fenbendazole added to the ration in doses of 20 and 40 mg/kg and the contrai group.

  6. Efectos del parasitismo sobre el tejido branquial en peces cultivados: estudio parasitologico e histopatologico Effect of the parasitism on the gill tissue of cultivated fishes: parasitological and histopathological studies

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    Maurício Laterça Martins

    1996-01-01

    Full Text Available One hundred four out of 225 diagnosticated cases were myxosporidian, monogenean, Ichthyophthirius multifiliis Fouquet, 1876 and bacterial diseases in Piaractus mesopotamicus Holmberg, 1887 (pacu, Colossoma macropomum Cuvier, 1818 (tambaqui and tambacu, at Aquaculture Center, Universidade Estadual Paulista (UNESP, Jaboticabal, São Paulo, Brazil, between 1992 and 1995. The gills were fixed in 10% buffered formalin solution to posterior histologic routine. It was observed Henneguya sp. cysts into the capillaries of the secondary lamellae, encapsulated by the respiratory epithelium cells. It provoked adherence of the adjacent lamellae, hyperplasia, congestion, oedema and epithelium displacement. Monogeneans infestations by Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 and Ancyrocephalinae sub-family caused light inflammatory reaction and hyperplasia. In severe infestations was observed hyperplasia of primary lamellae, necrosis, oedema, respiratory epithelium displacement, ruptured pillar cells and telangiectasis. Response to I. multifiliis was limited to surrounding epithelial cells in young fishes and hyperplasia, necrosis, inflammatory infiltrate and oedema in old fishes. Such lesions iniciate hyperplasic and oedematous process that with inflammation of the parasitic sites, provoked alterations over gases and ions interchange surface and consequently fish metabolism.

  7. Hematological and morphometric blood value of four cultured species of economically important tropical foodfish

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    Genoefa Amália Dal'Bó

    Full Text Available The use and validation of fish health monitoring tools have become increasingly evident due to aquaculture expansion. This study investigated the hematology and blood morphometrics of Piaractus mesopotamicus, Brycon orbignyanus, Oreochromis niloticus and Rhamdia quelen. The fish were kept for 30 days in 300-liter aquariums, after which they were anesthetized with benzocaine and blood was collected from caudal vessels. In comparison to other species, B. orbignyanus presented the highest hematocrit (Ht, RBC averages and Mean Corpuscular Volume (MCV with a particular range of data. B. orbignyanus presented lower Ht, Hb, RBC averages and values, and Mean Corpuscular Hemoglobin Concentration (MCHC. Oreochromis niloticus presented lower Ht, Hb, RBC averages and values, and Mean Corpuscular Hemoglobin Concentration (MCHC. Rhamdia quelen and O. niloticus presented higher variation of White Blood Cells (WBC, neutrophils (Nf, lymphocytes (Lf, monocytes (Mf and thrombocytes (Trb. Data of large axes (LA, minor axes (MA, surface (SF and volume (VL are in the same variance range. This study has demonstrated that hematological variances can occur between animals of different species as well as of the same species.

  8. Ingestão de ração e comportamento de larvas de pacu em resposta a estímulos químicos e visuais Diet ingestion rate and pacu larvae behavior in response to chemical and visual stimuli

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    Marcelo Borges Tesser

    2006-10-01

    Full Text Available Este estudo foi realizado com o objetivo de comparar a influência dos estímulos visual e/ou químico de náuplios de Artemia e de dieta microencapsulada sobre a taxa de ingestão da dieta microencapusulada por larvas de pacu Piaractus mesopotamicus. Utilizou-se um esquema fatorial 7 x 4 (estímulos e idades com duas repetições. Verificou-se efeito da idade das larvas e dos estímulos, mas não houve efeito para a interação idade ´ estímulos. O estímulo químico da Artemia e ambos os estímulos da Artemia resultaram em maior taxa de ingestão de dieta inerte. Resultado intermediário foi obtido com o estímulo visual da dieta microencapsulada. O estímulo químico, em comparação ao estímulo visual da Artemia, resultou em maiores taxas de ingestão da dieta. Com o aumento da idade, houve incremento na taxa de ingestão. Os estímulos visual e químico dos náuplios e o estímulo visual da ração aumentaram a ingestão de dieta inerte por larvas de pacu. Náuplios de Artemia devem ser oferecidos antes do fornecimento da dieta inerte, pois podem auxiliar no processo de transição alimentar. Os resultados deste trabalho apontaram novas possibilidades de estudos com larvas de peixes neotropicais visando a substituição precoce do alimento vivo para o inerte.The effect of visual, chemical and the combination of both stimuli from Artemia nauplii and from microencapsulated diet on dry diet ingestion by pacu Piaractus mesopotamicus larvae was evaluated in this research. The experiment was analyzed as a 7 x 4 factorial arrangement (seven stimuli and four ages with two replicates. It was observed effect of larvae age and stimuli, but no interaction (age ´ stimuli was observed. The chemical effect from Artemia and both effects from Artemia resulted in higher ingestion rates. An intermediary result was obtained with visual effect from microencapsulated diet. The chemical stimulus from Artemia resulted in higher ingestion rates than that

  9. Considerações sobre a reprodução artificial e alevinagem de pacu (Piaractus mesopotamicus, Holmberg, 1887 em viveiros Considerations on artificial reproduction and fingerling culture of pacu (Piaractus mesopotamicus, Holmberg, 1887 in ponds

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    Carlos Roberto Padovani

    2000-05-01

    Full Text Available Este trabalho apresenta uma revisão bibliográfica sobre a reprodução artificial, incubação e alevinagem de pacu em viveiros de terra. As técnicas de propagação artificial possibilitam o suprimento de ovos para uma grande variedade de peixes destinados à criação em viveiros e outros corpos de água confinados, bem como para sistemas superintensivos. Essas técnicas tornaram igualmente possível introduzir várias espécies importantes de peixes em áreas geográficas separadas. Além disso, permitem a incubação, a eclosão de ovos e larvicultura em condições bem protegidas e independentes das condições climáticas. Dependendo do sistema, 20 a 70% dos ovos produzidos têm possibilidade de se transformarem em alevinos; em contrapartida, a taxa de sobrevivência, sob condições naturais, geralmente é muito inferior a 1% dos ovos produzidosThis paper presents a literature review on pacu artificial reproduction, incubation and fingerling culture of pacu in ponds. The techniques of artificial propagation facilitate egg supply for a great variety of fish set aside to be raised in ponds and other impounded water bodies, as well as for superintensive systems. Those techniques made it equally possible to introduce several important fish species in separate geographical areas. Besides, they allow incubation, eggs eclosion and larvae culture under protected conditions, independently of climatic conditions. Depending on the system perfection, 20 to 70% of the eggs are liable to hatch and produce fingerlings. On the other hand the survival rate under natural conditions is generally lower than 1% of eggs

  10. Chromosome mapping of repetitive sequences in four Serrasalmidae species (Characiformes

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    Leila Braga Ribeiro

    2014-01-01

    Full Text Available The Serrasalmidae family is composed of a number of commercially interesting species, mainly in the Amazon region where most of these fishes occur. In the present study, we investigated the genomic organization of the 18S and 5S rDNA and telomeric sequences in mitotic chromosomes of four species from the basal clade of the Serrasalmidae family: Colossoma macropomum, Mylossoma aureum, M. duriventre, and Piaractus mesopotamicus, in order to understand the chromosomal evolution in the family. All the species studied had diploid numbers 2n = 54 and exclusively biarmed chromosomes, but variations of the karyotypic formulas were observed. C-banding resulted in similar patterns among the analyzed species, with heterochromatic blocks mainly present in centromeric regions. The 18S rDNA mapping of C. macropomum and P. mesopotamicus revealed multiple sites of this gene; 5S rDNA sites were detected in two chromosome pairs in all species, although not all of them were homeologs. Hybridization with a telomeric probe revealed signals in the terminal portions of chromosomes in all the species and an interstitial signal was observed in one pair of C. macropomum.

  11. Gastrointestinal transit of extruded or pelletized diets in pacu fed distinct inclusion levels of lipid and carbohydrate

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    Claucia Aparecida Honorato

    2014-11-01

    Full Text Available The objective of this work was to evaluate the effect of pelletized or extruded diets, with different levels of carbohydrate and lipid, on the gastrointestinal transit time (GITT and its modulation in pacu (Piaractus mesopotamicus. One hundred and eighty pacu juveniles were fed with eight isonitrogenous diets containing two carbohydrate levels (40 and 50% and two lipid levels (4 and 8%. Four diets were pelletized and four were extruded. Carbohydrate and lipid experimental levels caused no changes to the bolus transit time. However, the bolus permanence time was related to diet processing. Fish fed pelletized diets exhibited the highest gastrointestinal transit time. Regression analysis of bolus behavior for pelletized and extruded diets with 4% lipid depicted different fits. GITT regression analysis of fish fed 8% lipid was fitted to a cubic equation and displayed adjustments of food permanence, with enhanced utilization of the diets, either with extruded or pelletized diets. GITT of fish fed extruded diets with 4% lipid was adjusted to a linear equation. The GITT of pacu depends on the diet processing and is affected by dietary levels of lipid and carbohydrate.

  12. Copper sulfate acute ecotoxicity and environmental risk for tropical fish

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    Adilson Ferreira da Silva

    2014-10-01

    Full Text Available The aim of this study was to estimate copper sulfate acute toxicity and to determine death percentage and environmental risk on guppy fish (Phallocerus caudimaculatus, zebrafish (Brachydanio rerio, mato grosso (Hyphessobrycon eques, and pacu (Piaractus mesopotamicus. Fish were exposed to 0.01, 0.03, 0.05, 0.07, 0.10, and 0.30 mg L-1 (guppy, 0.05, 0.07, 0.10, and 0.30 mg L-1 (zebrafish, 0.07, 0.10, 0.20, and 0.30 mg L-1 (mato grosso and 9.5, 10.0, 10.5, 11.0, 11.5, and 12.0 mg L-1 (pacu of copper sulfate, with triplicate control. The estimated 50% average lethal concentrations (LC50; 96 hours were 0.05 (guppy, 0.13 (zebrafish; 0.16 (mato grosso and 10.36 mg L-1 (pacu. Copper sulfate was extremely toxic for guppy, highly toxic for zebrafish and mato grosso and lightly toxic for pacu and presents environmental risk of high adverse effects on the guppy, zebrafish and mato grosso and moderate adverse effect to the pacu. Therefore, the guppy fish, zebrafish, and mato grosso are important alternatives for copper sulfate toxicity evaluation in waterbodies.

  13. Cross-amplification of heterologous microsatellite markers in Rhamdia quelen and Leporinus elongatus

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    Nelson Mauricio Lopera-Barrero

    2016-02-01

    Full Text Available Native fish species in Brazil are an asset in fish farming, but their natural stocks have been significantly reduced in recent years. To mitigate this negative impact, studies on fish conservation are being conducted and genetic tools for the discrimination of population parameters are increasingly achieving great importance. Current analysis evaluates a set of microsatellite heterologous primers in the jundiá (Rhamdia quelen and in the piapara (Leporinus elongatus. Samples from the caudal fin of 15 broodstock from each species were analyzed. DNA extraction was performed with NaCl protocol and the integrity of the extracted DNA was checked with agarose gel 1%. Twenty primers developed for Piaractus mesopotamicus, Colossoma macropomum, Prochilodus lineatus, Brycon opalinus and Oreochromis niloticus were evaluated. Cross amplification of four primers of the B. opalinus and P. lineatus species (BoM12, Pli43 and Pli60 in R. quelen and BoM2, Pli43 and Pli60 in L. elongatus was assessed. Primers of P. mesopotamicus, C. macropomum and O. niloticus showed no cross amplification in the two species analyzed. Results revealed the possibility of using the four amplified heterologous primers in genetic studies for R. quelen and L. elongatus.

  14. Parasitic fauna in hybrid tambacu from fish farms

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    Ronilson Macedo Silva

    2013-08-01

    Full Text Available The objective of this work was to evaluate the parasitic fauna of hybrid tambacu (Colossoma macropomum x Piaractus mesopotamicus from fish farms and the host-parasite relationship. A hundred and fourteen fish were collected from four fish farms in Macapá, in the state of Amapá, Brazil, 80.7% of which were infected by: Ichthyophthirius multifiliis (Ciliophora; Piscinoodinium pillulare (Dinoflagellida; Anacanthorus spatulatus, Notozothecium janauachensis, and Mymarothecium viatorum (Monogenoidea; Neoechinorhynchus buttnerae (Acanthocephala; Cucullanus colossomi (Nematoda; Perulernaea gamitanae (Lernaeidae; and Proteocephalidae larvae (Cestoda. A total of 8,136,252 parasites were collected from the examined fish. This is the first record of N. buttnerae, C. colossomi, N. janauachensis, M. viatorum, and Proteocephalidae for hybrid tambacu in Brazil. Ichthyophthirius multifiliis was the most prevalent parasite, whereas endohelminths were the less. A positive correlation was observed between number of I. multifiliis and total length and weight of fish, as well as between number of P. gamitanae and total length. The infection by I. multifiliis had association with the parasitism by Monogenoidea. Low water quality contributes to high parasitism of hybrid tambacu by ectoparasites, which, however, does not influence the relative condition factor of fish.

  15. Piscinoodinium pillulare (Schäperclaus, 1954 Lom, 1981 (Dinoflagellida infection in cultivated freshwater fish from the Northeast region of São Paulo State, Brazil: parasitological and pathological aspects

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    M. L. MARTINS

    Full Text Available The Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, received fishes for diagnosis from fish farmers reporting fish crowding at pond edges and in water inlets. Fifty-three out of 194 cases showed round to oval, immobile whitish structures, measuring up to 162 mm diameter, identified as the dinoflagellate Piscinoodinium pillulare. In 34 diagnosed cases the parasites were present in the gills, in 2 on body surface, and 9 in both. Thirty-one out of 53 were tambacu hybrids hosts; 7, Piaractus mesopotamicus; 6, Colossoma macropomum; 5, Leporinus macrocephalus; 3, Oreochromis niloticus; and 1, Prochilodus lineatus. Fish showed increased mucous production on body surface and gills, while ecchymosis in the caudal peduncle and operculum was present. The gills also showed paleness, congestion, and petechiae. Histopathology presented a great number of trophonts situated between secondary lamellae, fixed to or detached from the epithelium. Primary lamellae presented interstitial hemorrhages, severe hyperplasia of the epithelium, goblet cells, and mononuclear infiltrates. The present work is the first report of P. pillulare in Brazil and emphasizes the importance of this dinoflagellate which caused significant economic losses from 1995 through 1997.

  16. Pesque-solte: pesca repetitiva, variáveis hematológicas e parasitismo no peixe híbrido tambacu

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    Daniela Nomura Varandas

    2013-08-01

    Full Text Available O objetivo deste trabalho foi avaliar a resposta hematológica e parasitológica de tambacus (Colossoma macropomum x Piaractus mesopotamicus submetidos ao estresse de captura e a diferentes densidades de estocagem, em sistema de pesque-solte. Foram utilizados 210 peixes com peso médio inicial de 785,33±152,02 g e comprimento total médio de 34,43±2,21 cm, mantidos em viveiros escavados e divididos em três grupos: sem pesca e baixa densidade (G1, com pesca e baixa densidade (G2, e com pesca e alta densidade (G3. Não houve diferença significativa entre os valores médios da concentração de hemoglobina, do número de eritrócitos, da contagem diferencial de leucócitos e da glicose. Os peixes do grupo G3 apresentaram número maior de parasitos e trombócitos, e menor ganho de peso e hematócrito. A atividade de pesque-solte, aliada à alta densidade de estocagem, pode prejudicar o equilíbrio orgânico e o desempenho zootécnico, o que favorece a parasitose.

  17. Milt cryopreservation for rheophilic fish threatened by extinction in the Rio Grande, Brazil.

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    de Andrade, Estefânia Souza; Paula, Daniella Aparecida de Jesus; Felizardo, Viviane de Oliveira; Murgas, Luis David Solis; Veras, Galileu Crovatto; Vieira e Rosa, Priscila

    2014-01-01

    Specific protocols for milt cryopreservation have been established for some freshwater fish species. However, cryopreservation reduces sperm quality, giving unsatisfactory results in reproduction. The objective of this work was to evaluate the effect of different cryoprotectants on the quality of Prochilodus lineatus, Brycon orbignyanus and Piaractus mesopotamicus milt after cryopreservation. The milt was diluted in different cryoprotectant solutions containing 10% methanol, dimethyl sulfoxide, glycerol, propylene glycol or ethylene glycol combined with the Beltsville Thawing Solution extender (5%), then placed in the vapour of a liquid nitrogen (LN) storage tank for 24 h, after which they were immersed in LN. After rewarming, the rate (%) and duration (s) of milt motility and abnormal morphology were evaluated. All of cryoprotectant solutions tested used maintained the viability of P. lineatus and P. mesopotamicus milt. However, in P. lineatus, glycerol ensured a lower percentage of abnormal morphology. In case of P. mesopotamicus, all of the cryoprotectant solutions tested may be used in the cryopreservation process, with the exception of those containing glycerol. For B. orbignyanus, cryoprotectant solutions containing methanol and ethylene glycol are recommended for use in the cryopreservation process, although they reduced the quality of sperm post-rewarming.

  18. Assessment of elimination profile of albendazole residues in fish.

    Science.gov (United States)

    Busatto, Zenaís; de França, Welliton Gonçalves; Cyrino, José Eurico Possebon; Paschoal, Jonas Augusto Rizzato

    2018-01-01

    Few drugs are specifically regulated for aquaculture. Thus this study considered albendazole (ABZ) as a potential drug for use in fish, which, however, is not yet regulated for this application. ABZ is a broad-spectrum anthelmintic approved for farmed ruminants and recently considered for treatment of fish parasites. It is the subject of careful monitoring because of potential residues in animal products. This study evaluated the depletion of ABZ and its main known metabolites: albendazole sulfoxide - ABZSO, albendazole sulfone - ABZSO 2 and albendazole amino sulfone - ABZ-2-NH 2 SO 2 , in the fillets of the Neotropical Characin pacu, Piaractus mesopotamicus, which were fed diets containing 10 mg ABZ kg -1 body weight in a single dose. Fish were euthanised at 8, 12, 24, 48, 72, 96 and 120 hours after medication and the depletion profiles of ABZ, each metabolite and the sum of all marker residues were assessed and evaluated taking into account methodological variations regarding determination of the maximum residue limits adopted by different international regulating agencies for estimation of the withdrawal period (WP). The estimated WPs ranged from 2 to 7 days.

  19. Efeito do ambiente pós-transporte na recuperação dos indicadores de estresse de pacus juvenis, Piaractus mesopotamicus = Effect of post-transport environment on the stress indicators recovery of pacu juveniles , Piaractus mesopotamicus

    Directory of Open Access Journals (Sweden)

    Leonardo Susumu Takahashi

    2006-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a recuperação das respostas fisiológicas de estresse após transporte de pacus em diferentes condições de es tocagem. Após transporte por 2h30min, os peixes foram transferidos para tanque de terra ou para caixas de polietileno em laboratório. Houve significativa redução dos valores de cortisol observados na chegada 24 horas depois, nas duas condições de estocagem , enquanto a concentração de glicose caiu significativamente 72 horas depois nos peixes estocados no tanque de t 1erra e 120 horas nos peixes estocados no laboratório. A osmolalidade, sódio, potássio e cloreto suger em um retorno à homeostase durante o perío do de recuperação, principalmente nos peixes no tanque de terra. Os parâmetros hematológicos, sem efeito da condição de estocagem, não se caracterizaram indicadores sensíveis. Após o transporte, uma prática de manejo que causa estresse em peixes, o retorno às condições normais foi favorecido quando os pacus foram estocados em tanque de terra.The aim of this work was to evaluate the recovery of physiological stress responses after the transport of pacu juveniles in different stocking conditions. After being transported for 2 h30min, fish were transferred to earthen ponds or indoor polyethylene boxes. There was a significant reduction of cortisol values registered at fish arrival , 24 hours after, in both stocking conditions . The glucose concentration reduced significantly 72 hours after in fish stocked in earthen ponds , and 120 hours in fish stocked indoor. Osmolality, sodium, potassium and chloride behavior suggested the re-establishment of the homeostasis during the recovery period, mainly in fish kept in the earthen ponds. Concerning the hematological parameters, only hemoglobin concentration reduced significantly in the recovery period , without effect of stockingcondition, which does not characterize feasible indicators. After transport, a management procedure that causes stress in fish, the recovery of the basal condition was fa vored when pacu were stocked in earthen ponds.

  20. Caracterização da piscicultura na região do Vale do Ribeira - SP Characterization of fish farming in the Ribeira Valley region - SP

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    Daniela Castellani

    2005-02-01

    Full Text Available Este trabalho buscou caracterizar a piscicultura na Região do Vale do Ribeira quanto aos sistemas de manejo. Estudaram-se quarenta e duas pisciculturas sendo que, destas, 36 praticam o sistema semi-intensivo e seis o sistema intensivo, com os seguintes objetivos: engorda de peixes, produção de alevinos e pesque-pagues. Foram listadas 41 espécies de peixes cultivadas. Apenas 6 espécies são nativas da Bacia do Rio Ribeira de Iguape: lambari (Astyanax sp Linneaus, 1758, traíra (Hoplias malabaricus Bloch, 1794, robalo (Centropomus ssp Cuvier e Valenciennes, 1928, jundiá (Rhamdia quelen Quoy e Gaimard, 1824, cascudo (Hypostomus sp Marschall, 1873 e cará (Geophagus brasiliensis Quoy e Gaimard, 1824. Em 95% das pisciculturas foram verificadas fugas de peixes exóticos e alóctones dos cultivos. A tilápia nilótica (Oreochromis niloticus Linneaus, 1758 foi a espécie mais freqüente em escapes, e também é a segunda mais cultivada pelos piscicultores, perdendo somente para o pacu (Piaractus mesopotamicus Halmberg, 1887. Foi possível verificar mediante o cálculo da conversão alimentar, que há um desperdício anual de cerca de 32% da ração utilizada nos cultivos pesquisados. A piscicultura encontra-se em plena expansão nesta região, e já representa a atividade agropecuária mais importante após a bananicultura.The aim of this work was to characterize the fish farming in the Ribeira de Iguape Basin, southern São Paulo State (Brazil, in relation to the management systems. Forty two farms were studied. A semi-intensive system is used by 36 farmers, while an intensive system is used only by 6 studied farmers. Their objectives were raising fish, juvenile fish production and sportive fishery. Forty one fish species were found to be cultivated, but only six were native species from Ribeira Valley: lambari (Astyanax sp Linneaus, 1758, traíra (Hoplias malabaricus Bloch, 1794, robalo (Centropomus ssp Cuvier and Valenciennes, 1928, jundi

  1. Microbiological water quality and gill histopathology of fish from fish farming in Itapecuru-Mirim County, Maranhão State=Qualidade microbiológica da água e histopatologia de brânquias de peixes provenientes de pisciculturas do município de Itapecuru-Mirim, Estado do Maranhão

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    Flávio Ruas de Moraes

    2012-04-01

    Full Text Available The present study evaluated the microbiological water quality and tissue lesions in gills from Nile tilapia (Oreochromis niloticus and hybrid tambacu (Colossoma macropomum female x Piaractus mesopotamicus male. For this, water and gills were collected from fish farming at six locations in Itapecuru-Mirim County, Maranhão State. Microbiological water analyses revealed contamination by total coliforms, Escherichia coli and heterotrophic bacteria. In the gills, we observed a diversity of Gram-positive and Gram-negative bacteria. The tissue lesions were: lamellar fusion, interlamellar hyperplasia, sub-epithelial edema and telangiectasia. Inflammatory lesions were not observed. Significant statistical difference (p > 0.05 was not detected when comparing different gills lesions during rainy and dry season. The correlation between lesion and pond type was statistically different (p Com o objetivo de avaliar a qualidade microbiológica da água e as alterações teciduais em brânquias de tilápias do Nilo (Oreochromis niloticus e do híbrido tambacu (Colossoma macropomum fêmea x Piaractus mesopotamicus macho, coletou-se água de pisciculturas e brânquias de peixes de seis localidades do município de Itapecuru-Mirim, Estado do Maranhão. O exame microbiológico da água revelou poluição por coliformes totais, Escherichia coli e bactérias heterotróficas. Nas brânquias, observou-se uma variedade de bactérias Gram-positivas e negativas. As alterações teciduais observadas foram fusão de lamelas, hiperplasia interlamelar, edema subepitelial e telangiectasia, não sendo observadas lesões inflamatórias. Não houve diferença estatística (p > 0,05 quando se comparou diferentes tipos de lesões branquiais com os períodos de chuva ou de seca. A correlação de lesões e tipos de tanque demonstrou diferença estatística (p < 0,05 para fusão de lamelas e hiperplasia interlamelar que ocorreram com maior frequência em viveiro de terra. Quanto

  2. Genetic diversity of pacu and piapara broodstocks in restocking programs in the rivers Paraná and Paranapanema (Brazil

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    Nelson Mauricio Lopera-Barrero

    2016-09-01

    Full Text Available The genetic diversity of Piaractus mesopotamicus (pacu and Leporinus elongatus (piapara broodstocks used in restocking programs in the rivers Paraná and Paranapanema is analyzed. One hundred and twenty specimens (two broodstocks of each species from fish ponds in Palotina PR Brazil and in Salto Grande SP Brazil were assessed. Ten primers produced 96 fragments, comprising 68 (70.83% and 94 (97.92% polymorphic fragments for P. mesopotamicus and L. elongatus broodstocks, respectively. Differences (p < 0.05 in the frequency of 15 and 27 fragments were detected for each species, without exclusive fragments. Shannon Index (0.347 - 0.572 and the percentage of polymorphic fragments (57.3% - 94.8% revealed high intra-population genetic variability for all broodstocks. Results of molecular variance analyses (AMOVA showed that most variations do not lie between the broodstocks but within each broodstock (89%. Genetic (0.088 and 0.142 and identity (0.916 and 0.868 distance rates demonstrated similarity between the broodstocks of each species, corroborated by Fst (0.1023 and 010.27 and Nm (4.18 and 4.33 rates, with a slight genetic difference due to genic flux. High intrapopulation genetic variability and similarity between the broodstocks of each species was also detected, proving a common ancestry.

  3. Considerações sobre a reprodução artificial e alevinagem de pacu (Piaractus mesopotamicus, Holmberg, 1887) em viveiros Considerations on artificial reproduction and fingerling culture of pacu (Piaractus mesopotamicus, Holmberg, 1887) in ponds

    OpenAIRE

    Carlos Roberto Padovani; Claudio Luiz Bock

    2000-01-01

    Este trabalho apresenta uma revisão bibliográfica sobre a reprodução artificial, incubação e alevinagem de pacu em viveiros de terra. As técnicas de propagação artificial possibilitam o suprimento de ovos para uma grande variedade de peixes destinados à criação em viveiros e outros corpos de água confinados, bem como para sistemas superintensivos. Essas técnicas tornaram igualmente possível introduzir várias espécies importantes de peixes em áreas geográficas separadas. Além disso, permitem a...

  4. Substituição de alimento vivo por alimento inerte na larvicultura intensiva do tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus = Replacement of live food for inert food on larviculture of tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus

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    Danieli Cuzini Lombardi

    2008-10-01

    Full Text Available Com este trabalho objetivou-se avaliar a substituição de náuplios de Artemia salina por alimentos inertes durante a larvicultura do tambacu. Na primeira fase, com duração de 12 dias, as larvas foram alimentadas com: náuplio de Artemia salina, cyclop-eeze e ovo de Artemia salina. Na segunda fase, com duração de dez dias, foram utilizadas larvas alimentadas com náuplios de Artemia salina provenientes da primeira fase e testados os mesmos três alimentos. A qualidade da água manteve-se em condições adequadas para alarvicultura nas duas fases. As larvas da primeira fase alimentadas com náuplios de Artemia salina obtiveram os melhores resultados em crescimento, sobrevivência e desempenho produtivo. Na segunda fase, o crescimento, a sobrevivência e o desempenho produtivo das larvas alimentadas com náuplios de Artemia salina e ovo de Artemia salina foram semelhantes. Nas duas fases, o custo com alimento foi mais baixo nas larvas alimentadas com náuplios de Artemia salina. Os resultados obtidos mostram que nas duas fases de larvicultura testadas a oferta de náuplios de Artemia salina é a melhor estratégia alimentar por proporcionar boa sobrevivência, crescimento e bom desempenho produtivo, além de menor custo.The aim of this work was to evaluate the replacement of Artemia salina nauplii by inert food during larviculture of tambacu. On the first phase with duration of 12 days, the larvae were fed with one of the following foods: Artemia salina nauplii, cyclop-eeze or Artemia salina egg. On the second phase, with 10 days of duration, larvae fed with Artemia salina nauplii were utilized in the first experiment and the same food treatments were tested. Water quality was adequate forlarvae rearing in both phases. The larvae from the first phase that fed with Artemia salina nauplii presented better growth, survival rate and yield. On the second phase, the growth, survival and yield of larvae fed with Artemia salina nauplii and eggs were similar. On both phases, the food cost was lower for larvae fed with Artemia salina nauplii. The obtained results shown that on the two rearing phases the use of Artemia salina nauplii is the better feeding strategies, as the survival, growth, yield were greater than in the others treatments, and also showed the lower cost.

  5. Current State of Knowledge of the Concentration of Mercury and Other Heavy Metals in Fresh Water Fish in Colombia

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    Néstor Javier Mancera-Rodríguez

    2006-01-01

    Full Text Available One of the most important environmental problems in the country refers to the indiscriminate use of chemical precursors in illicit activities, the use of heavy metals as mercury in mining activities, the spill of served waters and another type of compound related with the industrial activities of raw and the inadequate agricultural practices. This has led to chemical contamination especially by heavy metals, considered one of the most dangerous for the aquatic ecosystems and the present species in them. Fish have the capacity to store these compounds in their organism in a concentration higher important indicators of the contamination level, but also this implies that their consumption can become a serious health problem for the populations that feeds from them. The concentration of heavy metals in fish of fresh water is better known in the basin of the Magdalena river, especially in the region of the Mojana and in the marshes of the south of the Department of Bolivar where the levels of contamination by mercury and other metals has been studied due to the development of multiple industrial activities, including gold mining and petrochemical industries. However, little is known in the country about the problem generated by the disposal heavy metals in rivers and lakes and their impact on the fish resource, deterioration of ecosystems and human health. Based in the current norms bio-assays have been used to check the effects of the aquatic contamination on fresh waters fish and the evaluation of at least three parameters (heavy metals, temperature, effluents in eight species of fresh waters fish: Carassius auratus, Oreochromis spp., Piractus brachypomus, Prochilodus magdalenae, Astyanax fasciatus, Colossoma bidens, Gambusia affinis and Grundulus bogotensis.

  6. Current state of knowledge of the concentration of mercury and other heavy metals in fresh water fish in Colombia

    International Nuclear Information System (INIS)

    Mancera Rodriguez, Nestor Javier; Alvarez Leon, Ricardo

    2006-01-01

    One of the most important environmental problems in the country refers to the indiscriminate use of chemical precursors in illicit activities, the use of heavy metals as mercury in mining activities, the spill of served waters and another type of compound related with the industrial activities of raw and the inadequate agricultural practices. This has led to chemical contamination especially by heavy metals, considered one of the most dangerous for the aquatic ecosystems and the present species in them. Fish have the capacity to store these compounds in their organism in a concentration higher than that in the surrounding environment (water), therefore, their concentration are important indicators of the contamination level, but also this implies that their consumption can become a serious health problem for the populations that feeds from them. The concentration of heavy metals in fish of fresh water is better known in the basin of the Magdalena river, especially in the region of the Mojana and in the marshes of the south of the department of Bolivar where the levels of contamination by mercury and other metals has been studied due to the development of multiple industrial activities, including gold mining and petrochemical industries. However, little is known in the country about the problem generated by the disposal heavy metals in rivers and lakes and their impact on the fish resource, deterioration of ecosystems and human health. Based in the current norms bio-assays have been used to check the effects of the aquatic contamination on fresh waters fish and the evaluation of at least three parameters (heavy metals, temperature, effluents) in eight species of fresh waters fish: carassius auratus, oreochromis spp., piractus brachypomus, prochilodus magdalenae, astyanax fasciatus, colossoma bidens, gambusia affinis and grundulus bogotensis

  7. Fontes e níveis de proteína bruta em dietas para alevinos de pacu (Piaractus mesopotamicus

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    Fernandes João Batista Kochenborger

    2000-01-01

    Full Text Available Foi conduzido um experimento, com 100 dias duração, utilizando-se 288 alevinos de pacu, distribuídos em 36 caixas de cimento amianto com volume de 100 litros, para avaliar a substituição da farinha de peixe por farelo de soja e os níveis protéicos nas dietas. Durante o período experimental, a temperatura média da água permaneceu em 28ºC e os demais parâmetros limnológicos (oxigênio dissolvido, pH, alcalinidade e condutividade apresentaram-se dentro dos níveis adequados para o desenvolvimento desta espécie. O delineamento experimental foi de blocos casualizados, em que foram avaliados nove tratamentos em esquema fatorial 3 x 3, três níveis de proteína bruta (22, 26 e 30% e três níveis de substituição da farinha de peixe pelo farelo de soja (0, 50 e 100%. O nível de 26% de proteína bruta foi mais adequado. A farinha de peixe pode ser substituída parcial ou totalmente pelo farelo de soja, sem influir no ganho de peso, na conversão alimentar, na taxa de crescimento específico e na taxa de eficiência protéica dos alevinos. A substituição das fontes protéicas também não influenciou a composição corporal dos peixes, a eficiência de retenção de nitrogênio, o nitrogênio corporal, a gordura corporal e o nitrogênio e a gordura no ganho de peso.

  8. Stress responses in juvenile pacu (Piaractus mesopotamicus submitted to repeated air exposure - DOI: 10.4025/actascianimsci.v30i1.3618 Stress responses in juvenile pacu (Piaractus mesopotamicus submitted to repeated air exposure - DOI: 10.4025/actascianimsci.v30i1.3618

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    Leonardo Susumu Takahashi

    2008-06-01

    Full Text Available Juvenis de pacu (5,2 Pacu juveniles (5.2 ± 1.5 g were submitted to two one-minute air exposures in a 24 h interval, and sampled before the exposure (control and 5, 15, 30 and 60 min, 24 and 48 h afterwards for whole-body cortisol, sodium, potassium and calcium ion concentrations. For the first air exposure, there was a trend of increased cortisol concentration after 15 min, whereas in the second air exposure, the cortisol concentration increased significantly within 5 min after stress was induced. Sodium ion concentration increased significantly 24 h after both air exposures. Potassium concentration presented fluctuations over the experimental period. Calcium ion concentration increased progressively from 5 to 30 min, in both air exposures. The repeated air exposures exacerbated the cortisol response, but they did not affect the recovery ability of pacu over the experimental period. Additionally, the whole-body cortisol measurement might be a reliable indicator of stress, when sampled fish are smaller and blood volumes are very low, making samples inadequate for analysis1,5 g foram submetidos a duas exposições aéreas de um minuto, em intervalo de 24 horas, e amostrados antes da exposição (controle e 5, 15, 30 e 60 min, 24 e 48 horas depois para análise da concentração corporal de cortisol e dos íons sódio, potássio e cálcio. Na primeira exposição, os peixes apresentaram concentrações de cortisol aumentadas a partir de 15 min, embora não diferissem estatisticamente do controle. Na segunda exposição, a concentração de cortisol aumentou significativamente aos 5 min, retornando às concentrações equivalentes às dos peixes-controle em 30 min. A concentração do íon sódio aumentou significativamente 24 horas depois das duas exposições aéreas. A concentração do íon potássio apresentou flutuações durante o experimento, enquanto a do cálcio apresentou-se reduzida aos 5 min, aumentando gradativamente até os 30 min, nas duas exposições. A repetição do fenômeno estressor exacerbou a liberação de cortisol, mas não afetou a capacidade de recuperação dos peixes. A análise do cortisol tecidual pode ser considerada um indicador confiável de estresse.Pacu juveniles (5.2 ± 1.5 g were submitted to two one-minute air exposures in a 24 h interval, and sampled before the exposure (control and 5, 15, 30 and 60 min, 24 and 48 h afterwards for whole-body cortisol, sodium, potassium and calcium ion concentrations. For the first air exposure, there was a trend of increased cortisol concentration after 15 min, whereas in the second air exposure, the cortisol concentration increased significantly within 5 min after stress was induced. Sodium ion concentration increased significantly 24 h after both air exposures. Potassium concentration presented fluctuations over the experimental period. Calcium ion concentration increased progressively from 5 to 30 min, in both air exposures. The repeated air exposures exacerbated the cortisol response, but they did not affect the recovery ability of pacu over the experimental period. Additionally, the whole-body cortisol measurement might be a reliable indicator of stress, when sampled fish are smaller and blood volumes are very low, making samples inadequate for analysis

  9. Proposed method for agglutinating antibody titer analysis and its use as indicator of acquired immunity in pacu, Piaractus mesopotamicus

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    JD Biller-Takahashi

    Full Text Available Antibody can be assessed by agglutinating antibody titer which is a quantitative measure of circulating antibodies in serum from fish previously immunized. The antibody evaluation has been performed with different fish species, and is considered a reliable method that can be applied to confirm several hypothesis regarding acquired immunity, even in conjunction with precise methods to describe immune mechanisms. In order to provide appropriate analytical methods for future studies on the specific immune system of native fish, the present study standardized on assay to measure the serum agglutinating antibody titer produced after immunization with inactivated A. hydrophila and levamisole administration in pacu. It was possible to determine the agglutinating antibodies titer in a satisfactorily way in pacu immunized with inactive A. hydrophila, and the highest titers were observed on fish fed with levamisole.

  10. Effect of Aloe vera extract on the improvement of the respiratory activity of leukocytes of matrinxã during the transport stress

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    Fábio Sabbadin Zanuzzo

    2012-10-01

    Full Text Available This study evaluated the effect of extract of Aloe vera in the transport water of matrinxã (Brycon amazonicus fish on stress response and leukocyte respiratory activity. Fish was transported for 4 h in water containing Aloe at levels 0; 0.02; 0.2 and 2 mg/L, and sampled before transport 2, 4, 24 and 96 h after for determination of plasma glucose and respiratory activity of leukocytes. An additional in vitro assay was conducted with another fish species, pacu (Piaractus mesopotamicus, to test the respiratory burst of leukocytes exposed to Aloe extract (0.0, phosphate-buffered saline (PBS only at 0.1, 0.2, 0.5 and 1 mg/L. Plasma glucose increased after 2 and 4 h of transport and returned to control levels within 24 h, but the addition of Aloe in the transport water did not affect the level of blood glucose. However, at 2 h of transport, Aloe enhanced the respiratory activity of leukocytes in a dose-dependent way. The highest value of respiratory burst activity of leukocytes was observed in the fish transported in water containing Aloe at 2 mg/L. The enhancing effect of the plant extract on the production of oxygen radicals was confirmed in vitro in leukocytes of pacu incubated in Aloe at concentrations 0.1 and 0.2 mg/L. The results suggest that Aloe vera is a modulator of the immune system in fish improving the innate immune response tested.

  11. Phylogeny of the Serrasalmidae (Characiformes based on mitochondrial DNA sequences

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    Guillermo Ortí

    2008-01-01

    Full Text Available Previous studies based on DNA sequences of mitochondrial (mt rRNA genes showed three main groups within the subfamily Serrasalminae: (1 a "pacu" clade of herbivores (Colossoma, Mylossoma, Piaractus; (2 the "Myleus" clade (Myleus, Mylesinus, Tometes, Ossubtus; and (3 the "piranha" clade (Serrasalmus, Pygocentrus, Pygopristis, Pristobrycon, Catoprion, Metynnis. The genus Acnodon was placed as the sister taxon of clade (2+3. However, poor resolution within each clade was obtained due to low levels of variation among rRNA gene sequences. Complete sequences of the hypervariable mtDNA control region for a total of 45 taxa, and additional sequences of 12S and 16S rRNA from a total of 74 taxa representing all genera in the family are now presented to address intragroup relationships. Control region sequences of several serrasalmid species exhibit tandem repeats of short motifs (12 to 33 bp in the 3' end of this region, accounting for substantial length variation. Bayesian inference and maximum parsimony analyses of these sequences identify the same groupings as before and provide further evidence to support the following observations: (a Serrasalmus gouldingi and species of Pristobrycon (non-striolatus form a monophyletic group that is the sister group to other species of Serrasalmus and Pygocentrus; (b Catoprion, Pygopristis, and Pristobrycon striolatus form a well supported clade, sister to the group described above; (c some taxa assigned to the genus Myloplus (M. asterias, M tiete, M ternetzi, and M rubripinnis form a well supported group whereas other Myloplus species remain with uncertain affinities (d Mylesinus, Tometes and Myleus setiger form a monophyletic group.

  12. Growth and hematology of juvenile pacu Piaractus mesopotamicus (Holmberg 1887 fed with increasing levels of vitamin E (DL-α-tocopheryl acetate

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    RICARDO Y. SADO

    2013-03-01

    Full Text Available Intensive fish production systems are characterized by 100% artificial feeding, so any dietary imbalances or deficiencies may lead to diseases outbreaks and economic losses. This study was set out to determine the effects of increasing levels of dietary vitamin E on growth and hematology of juvenile pacu. Fishes were fed for 90 days, twice a day until apparent satiation with semi-purified diets containing 0.0; 25; 50; 150; 300 or 600 mg.kg−1 diet DL-α-tocopheryl acetate in a completely randomized design trial (n=4; biometrical and hematological data were collected and analyzed. Fishes fed with vit E diet (150 mg.kg−1 showed higher (p<0.05 weight gain and specific growth. Hematocrit, erythroblast number and total plasma protein were increased (p<0.05 in fishes fed diet with no vit E diet. Vitamin E supplementation in artificial diets for pacu is essential for growth and maintenance of normal erythropoiesis.

  13. CARACTERIZACIÓN Y EVALUACIÓN in vivo E in vitro DEL LIPOPOLISACÁRIDO DE Aeromonas hydrophila

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    A P JIMENEZ

    2008-05-01

    Full Text Available A partir de una cepa de A. hydrophila aislada de un brote de enfermedad septicémica en Tilapia nilótica (Piaractus brachypomusoreochromis niloticus, se obtuvieron extractos de lipopolisacárido (LPS crudo (29,5 mg/ml y semipurificado (106,5 mg/ml mediante la técnica fenol-agua caliente descrita por Westphal, Jann (1965. La presencia de proteína fue del 2,3% para el extracto crudo y de 0,1% para el semipurificado; la concentración de polisacáridos osciló entre el 15 y 26%. En electroforesis (SDS-PAGE se observaron bandas de 14 Kd correspondientes al oligosacárido central y al lípido A del LPS. Tres ratones de 25-35 g fueron inoculados intraperitonealmente con 25 mg/Kg de LPS cru-do, a partir de la primera hora todos los animales mostraron erizamiento, taquipnea e inapetencia; microscópicamente se detectó congestión hepática y pulmonar, hemorragias pulmonares y renales, marginación leucocitaria en hígado y pulmón con predominio de polimorfo-nucleares neutrófilos (PMN en todos los animales, mostrando un mayor efecto que el control inoculado con LPS de E. coli (Sigma® a la misma concentración. In vitro el LPS crudo a concentración de 10, 20 y 30 µg/ml indujo proliferación de células mono-nucleares murinas (2 x 10 5 en 200 µl de medio DMEM por incorporación de timidina tritiada; tanto el LPS control (E. coli, como el LPS crudo de A. hydrophila mostraron cuentas por minuto (CPM ascendentes de manera dosis dependiente, el LPS de A. hydrophila desencadeno una proliferación muy similar a la inducida por el control.

  14. Efeito do ambiente pós-transporte na recuperação dos indicadores de estresse de pacus juvenis, Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v28i4.610 Effect of post-transport environment on the stress indicators recovery of pacu juveniles , Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v28i4.610

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalbello Biller

    2006-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a recuperação das respostas fisiológicas de estresse após transporte de pacus em diferentes condições de es tocagem. Após transporte por 2h30min, os peixes foram transferidos para tanque de terra ou para caixas de polietileno em laboratório. Houve significativa redução dos valores de cortisol observados na chegada 24 horas depois, nas duas condições de estocagem , enquanto a concentração de glicose caiu significativamente 72 horas depois nos peixes estocados no tanque de t 1erra e 120 horas nos peixes estocados no laboratório. A osmolalidade, sódio, potássio e cloreto suger em um retorno à homeostase durante o perío do de recuperação, principalmente nos peixes no tanque de terra. Os parâmetros hematológicos, sem efeito da condição de estocagem, não se caracterizaram indicadores sensíveis. Após o transporte, uma prática de manejo que causa estresse em peixes, o retorno às condições normais foi favorecido quando os pacus foram estocados em tanque de terra.The aim of this work was to evaluate the recovery of physiological stress responses after the transport of pacu juveniles in different stocking conditions. After being transported for 2 h30min, fish were transferred to earthen ponds or indoor polyethylene boxes. There was a significant reduction of cortisol values registered at fish arrival , 24 hours after, in both stocking conditions . The glucose concentration reduced significantly 72 hours after in fish stocked in earthen ponds , and 120 hours in fish stocked indoor. Osmolality, sodium, potassium and chloride behavior suggested the re-establishment of the homeostasis during the recovery period, mainly in fish kept in the earthen ponds. Concerning the hematological parameters, only hemoglobin concentration reduced significantly in the recovery period , without effect of stocking condition, which does not characterize feasible indicators. After transport, a management procedure that causes stress in fish, the recovery of the basal condition was fa vored when pacu were stocked in earthen ponds.

  15. Avaliação do crescimento e do custo da alimentação do pacu (Piaractus mesopotamicus Holmberg, 1887 submetido a ciclos alternados de restrição alimentar e realimentação Evaluation of the growth and feeding costs of pacu (Piaractus mesopotamicus submitted to alternate cycles of feeding restriction and refeeding

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    Valéria Leão Souza

    2003-02-01

    Full Text Available Avaliaram-se os efeitos da utilização de ciclos alternados de restrição alimentar e realimentação no crescimento do pacu, durante o período de engorda, e a viabilidade desta prática na produção comercial da espécie. Juvenis foram distribuídos em três tanques e submetidos a diferentes manejos alimentares, constituindo os tratamentos: A (alimentado ad libitum, B (restrição alimentar de 4 semanas, realimentado por 9 semanas e C (6 semanas de restrição alimentar, realimentado por 7 semanas, em um total de 13 semanas por ciclo (4 ciclos experimentais. No final de cada ciclo alimentar, 20 peixes de cada tratamento foram amostrados e os dados biométricos registrados. Os valores obtidos para peso, comprimento total e fator de condição (K foram submetidos a ANOVA e as médias comparadas pelo teste de Duncan. Os resultados mostraram que o tratamento C é o mais indicado somente para outono/inverno, promovendo maior crescimento, menor custo com ração, baixa conversão alimentar e maior receita líquida parcial. Entretanto, durante as estações mais quentes do ano (primavera/verão outros programas de alimentação devem ser testados, utilizando-se períodos mais curtos de restrição alimentar. Quando se tratou da produção anual, o tratamento A respondeu melhor em termos de biomassa produzida, apesar do maior gasto com alimentação, visto que, com o aumento da temperatura, o crescimento dos peixes dos demais tratamentos ficou prejudicado.The present study evaluated the effects of alternating food restriction and refeeding cycles on the growth of pacu, during the growout phase and the viability of this practice in the commercial production of the species. Juvenile fish were distributed in 3 tanks and submitted to different feeding strategies: group A (fed ad libitum daily, B (food restricted to 4 weeks and refed for 9 weeks and C (food restricted to 6 weeks and refed for 7 weeks totalizing 13 weeks per cycle (4 experimental cycles. At the end of each feeding cycle, 20 fish per treatment were sampled and the biometric data were registered. Values of weight, total length and condition factor (K were submitted to ANOVA and the averages were compared by Duncan test. The results showed that the treatment C presented better results only in autumn/winter periods, promoting better growth, lower cost ration, lower food conversion and better partial net income. Otherwise, during the warmer periods of the year (spring/summer other feeding strategies must be tested, utilizing shorter periods of food restriction. Regarding to the annual production, the treatment A showed higher biomass, although higher feeding costs. With the increase in the temperature, the growth of the fish from the other treatments was delayed.

  16. Substituição de alimento vivo por alimento inerte na larvicultura intensiva do tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v30i4.3835 Replacement of live food for inert food on larviculture of tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v30i4.3835

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    Levy de Carvalho Gomes

    2009-03-01

    Full Text Available Com este trabalho objetivou-se avaliar a substituição de náuplios de Artemia salina por alimentos inertes durante a larvicultura do tambacu. Na primeira fase, com duração de 12 dias, as larvas foram alimentadas com: náuplio de Artemia salina, cyclop-eeze e ovo de Artemia salina. Na segunda fase, com duração de dez dias, foram utilizadas larvas alimentadas com náuplios de Artemia salina provenientes da primeira fase e testados os mesmos três alimentos. A qualidade da água manteve-se em condições adequadas para a larvicultura nas duas fases. As larvas da primeira fase alimentadas com náuplios de Artemia salina obtiveram os melhores resultados em crescimento, sobrevivência e desempenho produtivo. Na segunda fase, o crescimento, a sobrevivência e o desempenho produtivo das larvas alimentadas com náuplios de Artemia salina e ovo de Artemia salina foram semelhantes. Nas duas fases, o custo com alimento foi mais baixo nas larvas alimentadas com náuplios de Artemia salina. Os resultados obtidos mostram que nas duas fases de larvicultura testadas a oferta de náuplios de Artemia salina é a melhor estratégia alimentar por proporcionar boa sobrevivência, crescimento e bom desempenho produtivo, além de menor custo.The aim of this work was to evaluate the replacement of Artemia salina nauplii by inert food during larviculture of tambacu. On the first phase with duration of 12 days, the larvae were fed with one of the following foods: Artemia salina nauplii, cyclop-eeze or Artemia salina egg. On the second phase, with 10 days of duration, larvae fed with Artemia salina nauplii were utilized in the first experiment and the same food treatments were tested. Water quality was adequate for larvae rearing in both phases. The larvae from the first phase that fed with Artemia salina nauplii presented better growth, survival rate and yield. On the second phase, the growth, survival and yield of larvae fed with Artemia salina nauplii and eggs were similar. On both phases, the food cost was lower for larvae fed with Artemia salina nauplii. The obtained results shown that on the two rearing phases the use of Artemia salina nauplii is the better feeding strategies, as the survival, growth, yield were greater than in the others treatments, and also showed the lower cost.

  17. Métodos de coleta de fezes e determinação dos coeficientes de digestibilidade da fração protéica e da energia de alimentos para o pacu, Piaractus mesopotamicus (Holmberg, 1887 Fecal collection methods and determination of crude protein and of gross energy digestibility coefficients of feedstuffs for pacu, Piaractus mesopotamicus (Holmberg, 1887

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    Eduardo Gianini Abimorad

    2004-10-01

    Full Text Available Para melhorar a alimentação do pacu (Piaracatus mesopotamicus, é necessário conhecer o nível de aproveitamento dos ingredientes utilizados em suas dietas. Neste trabalho, inicialmente, foram analisados quatro métodos de coleta de fezes, em função da precisão e da versatilidade (dissecação, extrusão, Guelph e Guelph modificado, e o tempo entre as coletas de fezes nos sistemas de Guelph, por intermédio do coeficiente de digestibilidade da proteína bruta de uma dieta-referência para o pacu. Não houve diferença entre os métodos de coleta de fezes; já os intervalos de tempo das coletas apresentaram diferenças, podendo interferir nos resultados de digestibilidade da proteína. Em uma segunda etapa, para determinação dos coeficientes de digestibilidade da proteína e da energia de cinco concentrados protéicos de origem animal, cinco de origem vegetal e quatro energéticos, foram utilizadas rações elaboradas com 69,5% de uma dieta-referência, 30% do ingrediente teste e 0,5% de Cr2O3, utilizando o método de extrusão manual para a coleta de fezes. Os valores de digestibilidade da proteína da maioria dos alimentos apresentaram-se altos e não variaram estatisticamente, de 93,89 a 75,73% para o farelo de trigo e a farinha de penas, respectivamente. Entretanto, a farinha de sangue e a levedura apresentaram valores de digestibilidade da fração protéica significativamente inferiores (57,72 e 68,86%, respectivamente. Os coeficientes de digestibilidade da energia dos alimentos variaram consideravelmente, apresentando altos valores (acima de 90% para o sorgo, o farelo de arroz e as sojas crua e tostada, e baixos valores (menores que 70% para as farinhas de vísceras e de sangue, os farelos de soja e de algodão e a levedura. Quanto aos métodos de coleta de fezes, conclui-se que qualquer um pode ser adotado para a determinação de digestibilidade, desde que sejam rigorosamente aplicados. De maneira geral, a maioria dos concentrados protéicos pode ser utilizada como ótimas fontes de proteína, com exceção da farinha de sangue e a levedura, enquanto os alimentos energéticos confirmaram-se como excelentes fontes de energia em dietas para o pacu.To improve the pacu (Piaracatus mesopotamicus feeding in the growth phase, it's necessary to know the digestibility of the ingredients used in his diets. Initially, four fecal collection methods were analyzed (dissection, stripping, Guelph and modified Guelph, based on precision and versatility and also the most efficient time among fecal collection of the Guelph sedimentation systems, through crude protein digestibility coefficient of pacu basic diet. There was no difference among the fecal collection methods while the intervals of time among the collections were significantly different, which may interfere in the protein digestibility results. In a second stage, five proteins concentrated of animal origin, five of vegetable origin and four energetic were studied for estimating protein and energy digestibility coefficients using the stripping method. The rations contained 69.5% of a reference diet, 30.0% of the ingredient test and 0.5% of Cr2O3. In a general way, crude protein digestibility coefficients were high and did not differ from the wheat meal (93.89% and feather flour (75.73%, respectively. However, blood and yeast showed lower crude protein digestibility (57.72% and 68.86%, respectively. Gross energy digestibility coefficients varied considerably among the feedstuffs, showing high values (above 90% for the sorghum, rice meal and raw and toasted soy and lower values (smaller than 70% for poultry by-product and blood meal, soybean meal, cotton and yeast. However, with regard to the fecal collection methods, the results showed that anyone can be adopted with safety for digestibility determination, if used accurately. In a general way, most of protein concentrate can be used as a very good protein source, except for blood meal and the yeast. The energy concentrate revealed to be a source of energy in pacu diets.

  18. Importance of dam-free stretches for fish reproduction: the last remnant in the Upper Paraná River

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    Jislaine Cristina Silva

    2017-12-01

    Full Text Available Abstract Aim: This study uses the abundance of fish eggs and larvae to evaluate the importance of the main channel of the Paraná River and the adjacent areas of the floodplain, in the last dam-free stretch in the Brazilian territory, for the spawning and development of fish of different reproductive guilds, in order to obtain subsidies to assist in the management and conservation policies of this area, focusing on the maintenance of dam-free areas. Methods Data were taken quarterly from August 2013 to May 2015, in 25 sites, grouped into three biotopes: main channel, tributaries and lagoons. Possible spatial variations in fish spawning and development as well as composition and structure of larvae were evaluated. Results Higher densities of eggs were found in tributaries (Paracaí and Amambai rivers and greater densities of larvae were observed in lagoons (Saraiva. Significant differences in composition and structure of larvae were detected only between sampling stations. As for taxonomic composition, 29 taxa were recorded, mostly non-migratory. However, long-distance migratory were also widely distributed, such as Brycon orbignyanus, Pseudoplatystoma corruscans, Prochilodus lineatus, Piaractus mesopotamicus and Rhaphiodon vulpinus, as well as invasive species Platanichthys platana and Hemiodus orthonops. In turn, Salminus brasiliensis presented low occurrence. Conclusions This study evidenced that different species spawn in the region, mainly in tributaries, and their eggs and larvae are transported to the main channel of the Paraná River and adjacent lagoons, to complete their early development. The capture of larvae of important migratory species suggests that this environment still exhibits suitable conditions for their reproduction, mainly due to the presence of dam-free tributaries. Also, they emphasize the importance of the integrity of these environments for the maintenance of the regional fish fauna, and it is extremely important the

  19. ANÁLISIS ESTRUCTURAL DE FILETES SAJADOS DE HÍBRIDO DE CACHAMA Piaractus braquypomus x Colossoma macropomum UTILIZANDO BACTERIOCINAS PRODUCIDAS POR Lactobacillus plantarum LPBM10 EMPACADO AL VACÍO

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    Héctor Suárez M

    2008-08-01

    Full Text Available Objective. To determine microstructure, texture and sensory changes in cut cachama hybrid fillets. Materials and methods. Hybrid fillets that were vacuum packed for 30 days at 3°C were analyzed after preservative treatments by crude bacteriocins extract, lactic acid, and control by light microscopy. Results. Space among the muscle fibers increased gradually and the architectural arrangement was altered in all treatments throughout the entire storage period. The lowest alteration in connective tissue degradation and lowest increment in spaces between the muscular fibers was observed with the crude bacteriocin extract treatment. The instrumental textural analysis showed no statistical difference in the stability loss of tissues from fillets among treatments. Sensory analysis indicated that the lancing treatment was effective in diminishing the negative effect of intramuscular bones. The best scores were for cutting fillets with the bacteriocin treatment. Conclusions. The meat texture of fillets was affected during the storage period. Lancing is a procedure that enables the use of fillets without encountering the intramuscular bone problem. The use of crude bacteriocins extract prolongs the shelf-life of fillets.

  20. Diversidade genética de pacu utilizado em programas de repovoamento nos rios Tietê e Grande, Brasil

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    Ricardo Pereira Ribeiro

    2015-12-01

    Full Text Available Piaractus mesopotamicus é um peixe tropical que nos últimos anos tem apresentado uma diminuição no número de populações naturais. Programas de repovoamento vêm sendo utilizados como método de conservação, entretanto, o monitoramento genético das populações e dos estoques de reprodutores é importante para conferir a viabilidade desse tipo de programas. O objetivo do presente estudo foi avaliar de forma inédita a diversidade genética de populações selvagens (WPs e estoques de reprodutores (BSs de P. mesopotamicus utilizados em programas de repovoamento dos rios Tietê e Grande, através de marcadores microssatélite. Seis loci microssatélite foram amplificados usando DNA extraído de nadadeira caudal de 279 indivíduos adultos. Foi observada alta variabilidade genética intra-populacional, com medias de heterozigosidade observada entre 0.203 e 0.833. O número de alelos por locus foi de três (locus Pme28 e Pme32 a 13 (locus Pme4, Pme5 e Pme14 e houve diferenciação de alelos entre WPsxWPs e WPsxBSs. Essa diferenciação foi confirmada pela análise do dendrograma que mostrou a formação de três agrupamentos específicos. Observaram-se quatro alelos compartilhados entre WPs2012xBSs. Valores positivos de FIS mostraram a presença de endogamia em sete das 10 coletas realizadas nas WPs. A análise de AMOVA e do FST indicou moderada e muito alta diferenciação genética entre WPsxWPs e diferenciação genética muito alta em WPsxBSs. Esses resultados foram confirmados pelos valores de distância e identidade genética e pelo número de migrantes. Os resultados demonstraram uma adequada variabilidade genética intra-populacional, similaridade entre BSsxBSs e diferenciação genética entre WPs2011xWPs2012 e WPsxBSs. Observou-se parcialmente a presença de indivíduos oriundos do programa de repovoamento no ambiente natural.

  1. USE OF CONCRETE TANKS AS A PATTERN FOR RESEARCH WITH AQUATIC ANIMALS ESTUDO DE UMA SÉRIE DE TANQUES DE ALVENARIA COMO MODELO PARA CONDUÇÃO DE EXPERIMENTOS COM ORGANISMOS AQUÁTICOS

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    Delma Machado Cantisani Pádua

    2007-09-01

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    Water quality determines the success or failure of fish researches. A series of rectangular concrete tanks covered with nylon nets were evaluated as a pattern for conduction essay with aquatic animals, when environment conditions must be the same. Physical and chemical characteristics of water were observed. The tanks were populated with ten juvenile pacu (Piaractus mesopotamicus which were fed ad libitum twice a day. The experiment was carried out between November and February 1992/1993. In the middle of experiment five fishes were slaughtered in order to keep the biomass adequate until the end (87 days. Unsuitable limnologic conditions were detected in the lower waterflow tanks. The increased biomass and decreased waterflow were related to increased mortality and diseases. This kind of serial tanks building allows homogeneous environmental conditions and the waterflow was the parameter which must be carefully monitored.

    KEY-WORDS: Tanks; water quality; fish.

    Avaliou-se uma série de tanques de alvenaria, cobertos com tela de nylon, como modelo para ensaios com animais aquáticos, em que são exigidas igualdades das condições ambientais. Foram observados alguns parâmetros físicos e químicos da água. Os tanques foram povoados com dez juvenis de pacu, e a ração fornecida ad libitum duas vezes ao dia. O experimento foi conduzido entre novembro e fevereiro de 1992/1993. Na metade do experimento cinco peixes foram retirados para se manter a biomassa adequada até o final, aos 87 dias. Condições limnológicas inadequadas foram observadas nos tanques com menor taxa de renovação de água. O aumento da biomassa e o decréscimo da circulação de água foram relacionados com o aumento da mortalidade e doenças. Este