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Sample records for mesopotamicus xcolossoma macropomum

  1. Parasitic infections of Piaractus mesopotamicus and hybrid (P. mesopotamicus x Piaractus brachypomus) cultured in Brazil.

    PubMed

    Franceschini, Lidiane; Zago, Aline Cristina; Schalch, Sérgio Henrique Canello; Garcia, Fabiana; Romera, Daiane Mompean; da Silva, Reinaldo José

    2013-01-01

    This study evaluated the occurrence of parasitic infections in the "pacu" fish Piaractus mesopotamicus and the "patinga" hybrid (P. mesopotamicus x Piaractus brachypomus) in the northwest of São Paulo State, Brazil. Fish from the following three fish farms were evaluated every two months: A, a hatchery and larviculture farm (n = 16 pacu / n = 19 patinga), B, a growout farm (n = 35 patinga) and C, a fee-fishing property (n = 28 pacu / n = 7 patinga). Thirty-five fish from each property were collected from February 2010 to February 2011 and subjected to parasitological analysis. The parasites found were the following: Mymarothecium viatorum, Anacanthorus penilabiatus, Notozothecium janauachensis (Dactylogyridae, Monogenea), Trichodina spp., Ichthyophthirius multifiliis, Chilodonella sp. (Protozoa), Myxobolus spp., Henneguya spp. (Myxozoa), Rondonia rondoni, Contracaecum sp. (Nematoda), and Dolops carvalhoi (Crustacea). Of the fish examined, 62.9% from "A" and 100% from "B" and "C" were infested with at least one parasite species. Pacu fish (n = 44) showed a higher susceptibility to Anacanthorus penilabiatus infestations, whereas patinga (n = 61) were more susceptible to Mymarothecium viatorum (p < 0.05). Appropriate fish handling (nutrition, transport and storage), in conjunction with monitoring of water quality, can reduce the stress to which the farmed fish are exposed and is essential for pathogen control. PMID:24142174

  2. Histopathological changes in the head kidney induced by cadmium in a neotropical fish Colossoma macropomum

    PubMed Central

    Salazar-Lugo, R.; Vargas, A.; Rojas, L.; Lemus, M.

    2013-01-01

    We evaluated the effect of cadmium (Cd) on the structure and function of the head kidney in the freshwater fish Colossoma macropomum (C. macropomum). Juveniles were exposed to 0.1 mg/L CdCl2 for 31 days. Blood samples were examined using hematological tests and head kidney histology was determined by light microscopy. The concentration of Cd in the head and trunk kidneys was measured using an atomic absorption spectrophotometer. Cd produced histopathological changes in the head kidney, the most evident of these being: the thickening of the vein wall, an increase in the number of basophils/mast cells close to blood vessels and a severe depletion of hematopoietic precursors especially the granulopoietic series. In the blood, a decrease in the total leucocytes and hemoglobin concentration was observed. Cd-exposed fish showed higher Cd concentrations in the trunk kidney than the head kidney. In conclusion, exposure to Cd affected precursor hematopoietic cells in C. macropomum. PMID:26623329

  3. Histopathological changes in the head kidney induced by cadmium in a neotropical fish Colossoma macropomum.

    PubMed

    Salazar-Lugo, R; Vargas, A; Rojas, L; Lemus, M

    2013-01-01

    We evaluated the effect of cadmium (Cd) on the structure and function of the head kidney in the freshwater fish Colossoma macropomum (C. macropomum). Juveniles were exposed to 0.1 mg/L CdCl2 for 31 days. Blood samples were examined using hematological tests and head kidney histology was determined by light microscopy. The concentration of Cd in the head and trunk kidneys was measured using an atomic absorption spectrophotometer. Cd produced histopathological changes in the head kidney, the most evident of these being: the thickening of the vein wall, an increase in the number of basophils/mast cells close to blood vessels and a severe depletion of hematopoietic precursors especially the granulopoietic series. In the blood, a decrease in the total leucocytes and hemoglobin concentration was observed. Cd-exposed fish showed higher Cd concentrations in the trunk kidney than the head kidney. In conclusion, exposure to Cd affected precursor hematopoietic cells in C. macropomum. PMID:26623329

  4. Oxidative stress enzyme and histopathological lesions in Colossoma macropomum (pisces, ariidae) for environmental impact assessment

    NASA Astrophysics Data System (ADS)

    Andrade, Ticianne de Sousa de Oliveira Mota; Sousa, Debora Batista Pinheiro; Dantas, Janaina Gomes; Castro, Jonatas da Silva; Neta, Raimunda Nonata Fortes Carvalho

    2015-12-01

    This study used oxidative stress enzyme (Glutathione S-Transferase and Catalase), histopathological lesions (Branchial lesions) and biometric data in the freshwater fish tambaqui, Colossoma macropomum, to assess environmental impacts in an Environmental Protection Area at São Luis, Brazil. Fish were sampled from two locations (A1 = contaminated area and A2 = reference site) within the protected area on four occasions. The activity of catalase (CAT) and glutathione S-transferase (GST) in C. macropomum was compared with biometric data and histopathological lesions. Results have shown that biometric data decreased significantly in fish (p<0.05) at the contaminated site. The activity of CAT was higher in fish specifically caught in A1. A significant difference was observed in the GST activity in the liver of C. macropomum when comparing fish from the contaminated site and those from the reference site (p<0.05).

  5. Histopathological changes in the head kidney induced by cadmium in a neotropical fish Colossoma macropomum.

    PubMed

    Salazar-Lugo, R; Vargas, A; Rojas, L; Lemus, M

    2013-01-01

    We evaluated the effect of cadmium (Cd) on the structure and function of the head kidney in the freshwater fish Colossoma macropomum (C. macropomum). Juveniles were exposed to 0.1 mg/L CdCl2 for 31 days. Blood samples were examined using hematological tests and head kidney histology was determined by light microscopy. The concentration of Cd in the head and trunk kidneys was measured using an atomic absorption spectrophotometer. Cd produced histopathological changes in the head kidney, the most evident of these being: the thickening of the vein wall, an increase in the number of basophils/mast cells close to blood vessels and a severe depletion of hematopoietic precursors especially the granulopoietic series. In the blood, a decrease in the total leucocytes and hemoglobin concentration was observed. Cd-exposed fish showed higher Cd concentrations in the trunk kidney than the head kidney. In conclusion, exposure to Cd affected precursor hematopoietic cells in C. macropomum.

  6. [Histology of gill, liver and kidney in juvenile fish Colossoma macropomum exposed to three temperatures].

    PubMed

    Rojas, Luz-Marina; Mata, Claunis; Oliveros, Aridays; Salazar-Lugo, Raquel

    2013-06-01

    Abstract: Histology of gill, liver and kidney in juvenile fish Colossoma macropomum exposed to three temperatures. Water temperature is an important factor that affects growth and antioxidant enzyme activities in fish, and when adverse, it may trigger diseases in fish populations. C. macropomum is a freshwater neotropical fish widely distributed in South America and abundant in river basins as the Amazon and Orinoco. It is highly used for intensive aquaculture development and is a very important product for the local riverside economy in Venezuela. The purpose of our study was to examine the water temperature effect on gills, liver and kidneys of juvenile fishes of C macropomum. Eighteen juveniles with biometrical index of 17.87 +/- 7.88 cm and 87.69 +/- 34.23 g were respectively exposed to three culture temperatures (T18, T29 and T35 degrees C) during a period of 21 days. Histological analyses on gills, liver and kidney were made according to standard methodologies. Our results showed that these tissues exhibited normal citoarchitecture at T29. On the contrary, T18-gills displayed brachiallipid droplets inside brachial epithelium; and disorganization in the brachial tissue was observed at T35. Furthermore, we observed two kinds of hepatocytes (dark and light) on T180 degrees C-liver. The T35-liver samples showed cytoplasmatic granulation and damages in cytoplasmatic membrane. Kidney samples from T18 observed alterations in the cellular distribution of the hematopoietic tissue; while, at T35, the most important feature observed was the disorganization of the glomerular structure. We concluded that T18 and T35 are respectively critical and severe temperatures to C. macropomum; besides, the most sensible tissues to changes induced by temperature in this species were the liver and gills.

  7. Metabolic effects of trichlorfon (Masoten®) on the neotropical freshwater fish pacu (Piaractus mesopotamicus).

    PubMed

    Venturini, Francine P; Moraes, Fernanda D; Cortella, Lucas R X; Rossi, Priscila A; Cruz, Claudinei; Moraes, Gilberto

    2015-02-01

    Fish parasites are among the crucial limiting factors in aquaculture. The organophosphorous pesticide trichlorfon is widely used as an insecticide and against fish parasites worldwide. In this study, the effects of environmental trichlorfon on biochemical and physiological parameters were investigated in Piaractus mesopotamicus (pacu), a widely farmed fish in South America, through sublethal exposure (8 µg L(-1), 10 % of the LC50; 96 h) and recovery. The activity of brain acetylcholinesterase (AChE) was reduced after exposure (15.5 %) and remained decreased during the recovery (21.5 %). In white muscle, AChE activity decreased 31 % only after recovery. Alkaline phosphatase (ALP) and acid phosphatase (ACP) activities of the liver, muscle and plasma were steady during exposure. However, after the recovery period, ALP activity was increased in the liver and muscle and decreased in plasma, while ACP was increased in the liver and decreased in muscle. Intermediary metabolism was also affected by trichlorfon, depicting increase of energetic demand (hypoglycemia, neoglucogenesis and lipid catabolism), which remained even after recovery. These results indicate that P. mesopotamicus is adversely affected by sublethal concentrations of trichlorfon and are useful for assessing the impact as well as the pros and cons of its use in controlling fish parasites in aquaculture.

  8. Expression of Cellular Components in Granulomatous Inflammatory Response in Piaractus mesopotamicus Model

    PubMed Central

    Manrique, Wilson Gómez; da Silva Claudiano, Gustavo; de Castro, Marcello Pardi; Petrillo, Thalita Regina; Figueiredo, Mayra Araguaia Pereira; de Andrade Belo, Marco Antonio; Berdeal, María Isabel Quiroga; de Moraes, Julieta Engracia Rodini; de Moraes, Flávio Ruas

    2015-01-01

    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 106 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. PMID:25811875

  9. Studies of micronuclei and other nuclear abnormalities in red blood cells of Colossoma macropomum exposed to methylmercury

    PubMed Central

    da Rocha, Carlos Alberto Machado; da Cunha, Lorena Araújo; da Silva Pinheiro, Raul Henrique; de Oliveira Bahia, Marcelo; Burbano, Rommel Mario Rodríguez

    2011-01-01

    The frequencies of micronuclei (MN) and morphological nuclear abnormalities (NA) in erythrocytes in the peripheral blood of tambaqui (Colossoma macropomum), treated with 2 mg.L−1 methylmercury (MeHg), were analyzed. Two groups (nine specimens in each) were exposed to MeHg for different periods (group A - 24 h; group B - 120 h). A third group served as negative control (group C, untreated; n = 9). Although, when compared to the control group there were no significant differences in MN frequency in the treated groups, for NA, the differences between the frequencies of group B (treated for 120 h) and the control group were extremely significant (p < 0.02), thus demonstrating the potentially adverse effects of MeHg on C. macropomum erythrocytes after prolonged exposure. PMID:22215976

  10. Impact of stress on Aeromonas diversity in tambaqui (Colossoma macropomum) and lectin level change towards a bacterial challenge.

    PubMed

    Marques, Diego S C; Ferreira, Dijaci A; Paiva, Patrícia M G; Napoleão, Thiago H; Araújo, Janete M; Maciel Carvalho, Elba V M; Coelho, Luana C B B

    2016-12-01

    Tambaqui (Colossoma macropomum) is among the most cultivated fish species in tropical countries. Stress is the main cause of disease in fish farms. The genus Aeromonas is a common causative agent of fish diseases. This work reports the identification of Aeromonas species colonizing gills of C. macropomum submitted or not to a confinement stress. We also evaluated changes in serum levels of lectins (carbohydrate-binding proteins that are components of fish immune system) in tambaqui submitted to a challenge using two isolated Aeromonas strains. Gill tissues from stressed and unstressed fishes were used to isolate Aeromonas. Then 72 Aeromonas strains were isolated, 97% being from stressed fishes. Among these, 63 were identified at species level and 6 were classified as atypical Aeromonas strains. The most prevalent species were Aeromonas bestiarum and Aeromonas caviae and their strains were used in bacterial challenges. The lectin serum levels significantly increased after 24 h of infection with A. bestiarum; however, no significant increase was found for infection with A. caviae. In conclusion, C. macropomum gills are susceptible to colonization by different Aeromonas species, mainly at confinement stressful conditions, and serum lectins may have a role in the acute immunological response towards infection by A. bestiarum.

  11. Rearing temperature induces changes in muscle growth and gene expression in juvenile pacu (Piaractus mesopotamicus).

    PubMed

    Gutierrez de Paula, Tassiana; de Almeida, Fernanda Losi Alves; Carani, Fernanda Regina; Vechetti-Júnior, Ivan José; Padovani, Carlos Roberto; Salomão, Rondinelle Arthur Simões; Mareco, Edson Assunção; Dos Santos, Vander Bruno; Dal-Pai-Silva, Maeli

    2014-03-01

    Pacu (Piaractus mesopotamicus) is a fast-growing fish that is extensively used in Brazilian aquaculture programs and shows a wide range of thermal tolerance. Because temperature is an environmental factor that influences the growth rate of fish and is directly related to muscle plasticity and growth, we hypothesized that different rearing temperatures in juvenile pacu, which exhibits intense muscle growth by hyperplasia, can potentially alter the muscle growth patterns of this species. The aim of this study was to analyze the muscle growth characteristics together with the expression of the myogenic regulatory factors MyoD and myogenin and the growth factor myostatin in juvenile pacu that were submitted to different rearing temperatures. Juvenile fish (1.5 g weight) were distributed in tanks containing water and maintained at 24°C (G24), 28 °C (G28) and 32 °C (G32) (three replicates for each group) for 60 days. At days 30 and 60, the fish were anesthetized and euthanized, and muscle samples (n=12) were collected for morphological, morphometric and gene expression analyses. At day 30, the body weight and standard length were lower for G24 than for G28 and G32. Muscle fiber frequency in the <25 μm class was significantly higher in G24, and the >50 μm class was lower in G24. MyoD gene expression was higher in G24 compared with that in G28 and G32, and myogenin and myostatin mRNA levels were higher in G24 than G28. At day 60, the body weight and the standard length were higher in G32 but lower in G24. The frequency distribution of the <25 μm diameter muscle fibers was higher in G24, and that of the >50 μm class was lower in G24. MyoD mRNA levels were higher in G24 and G32, and myogenin mRNA levels were similar between G24 and G28 and between G24 and G32 but were higher in G28 compared to G32. The myostatin mRNA levels were similar between the studied temperatures. In light of our results, we conclude that low rearing temperature altered the expression of muscle

  12. Histochemical distribution of intestinal enzymes of juvenile pacu (Piaractus mesopotamicus) fed lyophilized bovine colostrum.

    PubMed

    Moretti, Débora B; Nordi, Wiolene M; Cruz, Thaline M P; Cyrino, José Eurico P; Machado-Neto, Raul

    2014-10-01

    Enzyme activity was evaluated in the intestine of juvenile pacu, Piaractus mesopotamicus, fed diets containing 0, 10 or 20 % of lyophilized bovine colostrum (LBC) inclusion for either 30 or 60 days. The enzymes intestinal acid and alkaline phosphatase (ACP and ALP, respectively), nonspecific esterase (NSE), lipase (LIP), dipeptidyl aminopeptidase IV (DAP IV) and leucine aminopeptidase (LAP) were studied using histochemistry in four intestinal segments (S1, S2, S3 and rectum). Moderate activity of the DAP IV was detected in the three last intestinal segments, but no differences among the treatments were detected. Enzymes LAP, NSE and LIP were weakly stained in all intestinal segments and the inclusion of 10 or 20 % of LBC in the diet commanded a moderate reaction to NSE in the S3 segment at day 60. ACP activity was detected only in the brush border of the S1 segment of fish fed 0 % LBC for either 30 or 60 days. The activity of ALP was very strong in the first intestinal segment, but a weak reaction was seen in the last segments. The inclusion of 20 % of LBC changed the pattern of staining to the ALP, eliciting moderate staining in S2 at day 30 and S1 at day 60. The consumption of diets containing LBC by juvenile pacu did not have significant implications in intestinal enzymatic activity, which still was not fully stimulated. PMID:24823663

  13. Migratory movements of pacu, Piaractus mesopotamicus, in the highly impounded Paraná River

    USGS Publications Warehouse

    Makrakis, M.C.; Miranda, L.E.; Makrakis, S.; Xavier, A.M.M.; Fontes, H.M.; Morlis, W.G.

    2007-01-01

    A mark-recapture study was conducted in 1997–2005 to investigate movements of stocked pacu, Piaractus mesopotamicus, in the Paraná River Basin of Brazil, Paraguay, and Argentina. Fish raised in cages within the Itaipu Reservoir and in ponds were tagged externally (n = 2976) and released in the Itaipu Reservoir (53.2%) and bays of its major tributaries (46.8%). In total, 367 fish (12.3%) were recaptured. In all, 91% of the pacu moved away from the release site; upstream movements were more extensive than downstream movements. Pacu traveled upstream a maximum of 422 km (average of 41.3 km) at a maximum rate of 26.4 km day−1 (av. 0.8). Downstream movements were limited in terms of number of individuals and distance moved. Fish released during the wet season moved farther than those released during the dry season, and feeding rather than spawning might have been the compelling reason for movement. Although fish passed downstream through dams, none of the marked fish were detected to have moved upstream through the passage facilities. Pacu showed movement patterns not radically different from those of other neotropical migratory species, but their migratory movements may not be as extensive as those of other large migratory species in the basin.

  14. Purification, characterization and substrate specificity of a trypsin from the Amazonian fish tambaqui (Colossoma macropomum).

    PubMed

    Marcuschi, Marina; Espósito, Talita S; Machado, Maurício F M; Hirata, Izaura Y; Machado, Marcelo F M; Silva, Márcia V; Carvalho, Luiz B; Oliveira, Vitor; Bezerra, Ranilson S

    2010-06-01

    An enzyme was purified from the pyloric caecum of tambaqui (Colossoma macropomum) through heat treatment, ammonium sulfate fractionation, Sephadex G-75 and p-aminobenzamidine-agarose affinity chromatography. The enzyme had a molecular mass of 23.9 kDa, NH(2)-terminal amino acid sequence of IVGGYECKAHSQPHVSLNI and substrate specificity for arginine at P1, efficiently hydrolizing substrates with leucine and lysine at P2 and serine and arginine at P1'. Using the substrate z-FR-MCA, the enzyme exhibited greatest activity at pH 9.0 and 50 degrees C, whereas, with BAPNA activity was higher in a pH range of 7.5-11.5 and at 70 degrees C. Moreover, the enzyme maintained ca. 60% of its activity after incubated for 3h at 60 degrees C. The enzymatic activity significantly decreased in the presence of TLCK, benzamidine (trypsin inhibitors) and PMSF (serine protease inhibitor). This source of trypsin may be an attractive alternative for the detergent and food industry. PMID:20438707

  15. Micronucleus frequency and hematologic index in Colossoma macropomum (Pisces, Ariidae) for environmental impact assessment at a protected area in Brazil

    SciTech Connect

    Sousa, Debora Batista Pinheiro; Neta, Raimunda Nonata Fortes Carvalho

    2014-10-06

    This study used micronucleus assays and erythrocyte indices in the freshwater fish tambaqui, Colossoma macropomum, to assess environmental impacts in the Environmental Protection Area at Maracanã, São Luis, Brazil. Fish were sampled from two locations within the protected area, Serena Lagoon and Ambude River, on four occasions. Biometric data (length and weight) and an aliquot of blood were collected from each fish for analysis. Erythrocyte indices including: mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were calculated, and blood samples were examined for micronuclei and nuclear morphological changes. Micronuclei were found in fish from both locations, although the frequency was higher in fish from Ambude River. Nuclear morphological changes were identified only in fish collected from Ambude River. Several nuclear morphological changes were found in erythrocytes stained with Giemsa, including: micronuclei and binucleate nuclei. On average, erythrocyte indices were lower in fish collected from Ambude River than in those from Serena Lagoon. Our results indicate that micronuclei and erythrocyte indices can be used in C. macropomum as indicators of environmental health.

  16. Acute and chronic toxicity of the benzoylurea pesticide, lufenuron, in the fish, Colossoma macropomum.

    PubMed

    Rafaela Leão Soares, Priscila; Lucas Corrêa de Andrade, André; Pinheiro Santos, Thamiris; Caroline Barros Lucas da Silva, Stephannie; Freitas da Silva, Jadson; Rodrigues Dos Santos, Amanda; Hugo Lima da Silva Souza, Elton; Magliano da Cunha, Franklin; Wanderley Teixeira, Valéria; Sales Cadena, Marilia Ribeiro; Bezerra de Sá, Fabrício; Bezerra de Carvalho Júnior, Luiz; Gonçalves Cadena, Pabyton

    2016-10-01

    Lufenuron is a benzoylurea insecticide that interfere in chitin synthesis in insects. Although lufenuron is widely used in agriculture and aquaculture, rare are studies described that relates to possible toxic effects in fish. This work aimed to evaluate acute and chronic toxic effects of benzoylurea pesticide (lufenuron) on biological parameters of Colossoma macropomum (Tambaqui). In the acute test, juveniles of Tambaqui were divided into control group and five experimental groups with exposure from 0.1 to 0.9 mg/L of lufenuron for 96 h. Animals were also submitted to chronic toxicity test for four months in concentrations of 0.1 and 0.3 mg/L of lufenuron, the concentration used in the treatment of ectoparasites in fish and 50% of LC50 96 h, respectively. The presence of hemorrhages was observed in eyes, fins and operculum of fish exposed to 0.7 and 0.9 mg/L of lufenuron. Histological analysis showed changes in the morphology of fish gills submitted to acute toxicity test, as lamellar aneurysm and blood congestion inside lamellae. Lufenuron promoted damage in fish retina as in ability to respond to stimuli in photoreceptors and in ON-bipolar cells in acute test. In chronic test, blood glucose analysis and morphometric parameters showed no significant differences (p > 0.05). In general, Tambaqui exhibited behaviors associated with stress when exposed to lufenuron. Thus, lufenuron showed several toxic effects in relation to biological parameters in Tambaqui. This concerns about the use and discard of lufenuron, and indicates the requirement of environmental actions to prevent potential contamination of aquatic biota. PMID:27448754

  17. Acute and chronic toxicity of the benzoylurea pesticide, lufenuron, in the fish, Colossoma macropomum.

    PubMed

    Rafaela Leão Soares, Priscila; Lucas Corrêa de Andrade, André; Pinheiro Santos, Thamiris; Caroline Barros Lucas da Silva, Stephannie; Freitas da Silva, Jadson; Rodrigues Dos Santos, Amanda; Hugo Lima da Silva Souza, Elton; Magliano da Cunha, Franklin; Wanderley Teixeira, Valéria; Sales Cadena, Marilia Ribeiro; Bezerra de Sá, Fabrício; Bezerra de Carvalho Júnior, Luiz; Gonçalves Cadena, Pabyton

    2016-10-01

    Lufenuron is a benzoylurea insecticide that interfere in chitin synthesis in insects. Although lufenuron is widely used in agriculture and aquaculture, rare are studies described that relates to possible toxic effects in fish. This work aimed to evaluate acute and chronic toxic effects of benzoylurea pesticide (lufenuron) on biological parameters of Colossoma macropomum (Tambaqui). In the acute test, juveniles of Tambaqui were divided into control group and five experimental groups with exposure from 0.1 to 0.9 mg/L of lufenuron for 96 h. Animals were also submitted to chronic toxicity test for four months in concentrations of 0.1 and 0.3 mg/L of lufenuron, the concentration used in the treatment of ectoparasites in fish and 50% of LC50 96 h, respectively. The presence of hemorrhages was observed in eyes, fins and operculum of fish exposed to 0.7 and 0.9 mg/L of lufenuron. Histological analysis showed changes in the morphology of fish gills submitted to acute toxicity test, as lamellar aneurysm and blood congestion inside lamellae. Lufenuron promoted damage in fish retina as in ability to respond to stimuli in photoreceptors and in ON-bipolar cells in acute test. In chronic test, blood glucose analysis and morphometric parameters showed no significant differences (p > 0.05). In general, Tambaqui exhibited behaviors associated with stress when exposed to lufenuron. Thus, lufenuron showed several toxic effects in relation to biological parameters in Tambaqui. This concerns about the use and discard of lufenuron, and indicates the requirement of environmental actions to prevent potential contamination of aquatic biota.

  18. Ultrastructural description of Myxobolus cuneus (Myxosporea) in the skeletal muscle and kidney of tropical farmed fish Piaractus mesopotamicus (Characiformes: Characidae).

    PubMed

    Manrique, Wilson Gómez; Figueiredo, Mayra Araguaia Pereira; de Andrade Belo, Marco Antonio; Martins, Maurício Laterça; Azevedo, Carlos

    2016-06-01

    This study characterizes by transmission electron microscopy (TEM) and morphometric features the myxozoan Myxobolus cuneus (Myxosporea) in Piaractus mesopotamicus and reports the skeletal muscle and kidney as site of infection. The register was based in 21 young fish from intensive fish farming in Southeast Brazil and the spores were analyzed in fresh-mounted slides of the infected organs stained with Toluidine blue and processed as usual for TEM. It differs from Myxobolus cunhai from the fish host and different polar capsule size, and from Myxobolus serrasalmi on the pyriform spore shape and an oval macrospore, differently to that reported in this study. Morphometric characteristics and TEM study confirmed the present material as M. cuneus.

  19. Ultrastructural description of Myxobolus cuneus (Myxosporea) in the skeletal muscle and kidney of tropical farmed fish Piaractus mesopotamicus (Characiformes: Characidae).

    PubMed

    Manrique, Wilson Gómez; Figueiredo, Mayra Araguaia Pereira; de Andrade Belo, Marco Antonio; Martins, Maurício Laterça; Azevedo, Carlos

    2016-06-01

    This study characterizes by transmission electron microscopy (TEM) and morphometric features the myxozoan Myxobolus cuneus (Myxosporea) in Piaractus mesopotamicus and reports the skeletal muscle and kidney as site of infection. The register was based in 21 young fish from intensive fish farming in Southeast Brazil and the spores were analyzed in fresh-mounted slides of the infected organs stained with Toluidine blue and processed as usual for TEM. It differs from Myxobolus cunhai from the fish host and different polar capsule size, and from Myxobolus serrasalmi on the pyriform spore shape and an oval macrospore, differently to that reported in this study. Morphometric characteristics and TEM study confirmed the present material as M. cuneus. PMID:27021179

  20. [Histopathology of liver, kidney and spleen of Piaractus mesopotamicus, Prochilodus lineatus and Pseudoplatystoma fasciatum infected by myxosporean parasite, caugth in Aquidauana River, State of Mato Grosso do Sul, Brazil].

    PubMed

    Campos, Cristiane M de; Moraes, Julieta R E de; Moraes, E Flávio R de

    2008-01-01

    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 5microm were stained with hematoxylin and eosin. Myxobolus porofilus, 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 to 50% of P. mesopotamicus and P. lineatus liver samples showed diffuse hepatodistrofy. Liver sections also showed concentric hialin structures in over 80% of samples and esteatosis in 50% of them. In P. mesopotamicus kidney, 95.23% of them showed tissue changes consisted of 60% with diffuse moderate nefrodistrofy and congestion of glomerular sinusoids. In P. lineatus kidney, 20% of the samples showed tissues changes. No heavy damage was observed in the fish spleen.

  1. Essential oils to control ichthyophthiriasis in pacu, Piaractus mesopotamicus (Holmberg): special emphasis on treatment with Melaleuca alternifolia.

    PubMed

    Valladão, G M R; Gallani, S U; Ikefuti, C V; da Cruz, C; Levy-Pereira, N; Rodrigues, M V N; Pilarski, F

    2016-10-01

    In vitro effect of the Melaleuca alternifolia, Lavandula angustifolia and Mentha piperita essential oils (EOs) against Ichthyophthirius multifiliis and in vivo effect of M. alternifolia for treating ichthyophthiriasis in one of the most important South American fish, Piaractus mesopotamicus (Holmberg), were evaluated. The in vitro test consisted of three EOs, each at concentrations of 57 μL L(-1) , 114 μL L (-1) , 227 μL L(-1) and 455 μL L (-1) , which were assessed once an hour for 4 h in microtitre plates (96 wells). The in vitro results demonstrated that all tested EOs showed a cytotoxic effect against I. multifiliis compared to control groups (P < 0.05). The in vivo treatment for white spot disease was performed in a bath for 2 h day(-1) for 5 days using the M. alternifolia EO (50 μL L (-1) ). In this study, 53.33% of the fish severely infected by I. multifiliis survived after the treatment with M. alternifolia (50 μL L (-1) ) and the parasitological analysis has shown an efficacy of nearly 100% in the skin and gills, while all the fish in the control group died. Furthermore, the potential positive effect of M. alternifolia EO against two emergent opportunistic bacteria in South America Edwardsiella tarda and Citrobacter freundii was discussed. PMID:26776242

  2. pH drop impacts differentially skin and gut microbiota of the Amazonian fish tambaqui (Colossoma macropomum).

    PubMed

    Sylvain, François-Étienne; Cheaib, Bachar; Llewellyn, Martin; Gabriel Correia, Tiago; Barros Fagundes, Daniel; Luis Val, Adalberto; Derome, Nicolas

    2016-01-01

    Aquatic organisms are increasingly exposed to lowering of environmental pH due to anthropogenic pressure (e.g. acid rain, acid mine drainages). Such acute variations trigger imbalance of fish-associated microbiota, which in turn favour opportunistic diseases. We used the tambaqui (Colossoma macropomum), an Amazonian fish tolerant to significant pH variation in its natural environment, to assess the response of fish endogenous microbiota to acute short-term acid stress. We exposed 36 specimens of tambaquis to acidic water (pH 4.0) over 2 consecutive weeks and sampled cutaneous mucus, feces and water at 0, 7 &14 days. The 16S RNA hypervariable region V4 was sequenced on Illumina MiSeq. After two weeks of acidic exposure, fecal and skin microbiota taxonomic structures exhibited different patterns: skin microbiota was still exhibiting a significantly disturbed composition whereas fecal microbiota recovered a similar composition to control group, thus suggesting a stronger resilience capacity of the intestinal microbiota than cutaneous microbiota. PMID:27535789

  3. pH drop impacts differentially skin and gut microbiota of the Amazonian fish tambaqui (Colossoma macropomum).

    PubMed

    Sylvain, François-Étienne; Cheaib, Bachar; Llewellyn, Martin; Gabriel Correia, Tiago; Barros Fagundes, Daniel; Luis Val, Adalberto; Derome, Nicolas

    2016-01-01

    Aquatic organisms are increasingly exposed to lowering of environmental pH due to anthropogenic pressure (e.g. acid rain, acid mine drainages). Such acute variations trigger imbalance of fish-associated microbiota, which in turn favour opportunistic diseases. We used the tambaqui (Colossoma macropomum), an Amazonian fish tolerant to significant pH variation in its natural environment, to assess the response of fish endogenous microbiota to acute short-term acid stress. We exposed 36 specimens of tambaquis to acidic water (pH 4.0) over 2 consecutive weeks and sampled cutaneous mucus, feces and water at 0, 7 &14 days. The 16S RNA hypervariable region V4 was sequenced on Illumina MiSeq. After two weeks of acidic exposure, fecal and skin microbiota taxonomic structures exhibited different patterns: skin microbiota was still exhibiting a significantly disturbed composition whereas fecal microbiota recovered a similar composition to control group, thus suggesting a stronger resilience capacity of the intestinal microbiota than cutaneous microbiota.

  4. pH drop impacts differentially skin and gut microbiota of the Amazonian fish tambaqui (Colossoma macropomum)

    PubMed Central

    Sylvain, François-Étienne; Cheaib, Bachar; Llewellyn, Martin; Gabriel Correia, Tiago; Barros Fagundes, Daniel; Luis Val, Adalberto; Derome, Nicolas

    2016-01-01

    Aquatic organisms are increasingly exposed to lowering of environmental pH due to anthropogenic pressure (e.g. acid rain, acid mine drainages). Such acute variations trigger imbalance of fish-associated microbiota, which in turn favour opportunistic diseases. We used the tambaqui (Colossoma macropomum), an Amazonian fish tolerant to significant pH variation in its natural environment, to assess the response of fish endogenous microbiota to acute short-term acid stress. We exposed 36 specimens of tambaquis to acidic water (pH 4.0) over 2 consecutive weeks and sampled cutaneous mucus, feces and water at 0, 7 & 14 days. The 16S RNA hypervariable region V4 was sequenced on Illumina MiSeq. After two weeks of acidic exposure, fecal and skin microbiota taxonomic structures exhibited different patterns: skin microbiota was still exhibiting a significantly disturbed composition whereas fecal microbiota recovered a similar composition to control group, thus suggesting a stronger resilience capacity of the intestinal microbiota than cutaneous microbiota. PMID:27535789

  5. Effects of re-stripping on the seminal characteristics of pacu (Piaractus mesopotamicus) during the breeding season.

    PubMed

    Kuradomi, Rafael Y; De Souza, Thiago G; Foresti, Fausto; Schulz, Rüdiger W; Bogerd, Jan; Moreira, Renata G; Furlan, Luiz R; Almeida, Eduardo A; Maschio, Lucilene R; Batlouni, Sergio R

    2016-01-01

    Seminal characteristics in teleost fish with an annual reproductive period, such as pacu (Piaractus mesopotamicus), may vary during the breeding season. The sperm formed before the beginning of the spawning period may be stored for a long time, causing damage to the cells. Therefore, re-stripping may be an important way to eliminate the "old" and allow for the collection of "new" spermatozoids. In this study, we analyzed the seminal characteristics of hormonally induced pacu at the beginning, middle and end of the breeding season, and we analyzed samples from re-stripped males (stripped first at the beginning, re-stripped in the middle, and re-stripped again at the end of the season) during two breeding seasons. The sperm density, ionic composition, pH, and osmolality were similar among the groups. The semen volume, seminal plasma protein concentration and incidence of morphologically anomalous sperm increased over time. In addition, some parameters that are associated with good-quality semen decreased, such as sperm motility, viability and DNA integrity. Moreover, we observed a positive association among motility, viability and DNA integrity for sperm with elevated 11-ketotestosterone, but there was no such association for fshb or lhb mRNA levels in the pituitary. The semen that was obtained earlier (at the beginning) or from re-stripped males exhibited better characteristics than the other samples collected. In conclusion, collecting semen from pacu at the end of breeding season should be avoided; it is preferable to strip early and then re-strip later in the season, and this approach may be used for diverse aquaculture purposes.

  6. The basis of vagal efferent control of heart rate in a neotropical fish, the pacu, Piaractus mesopotamicus.

    PubMed

    Taylor, E W; Leite, C A C; Florindo, L H; Beläo, T; Rantin, F T

    2009-04-01

    The role of the parasympathetic nervous system, operating via the vagus nerve, in determining heart rate (f(H)) and cardiorespiratory interactions was investigated in the neotropical fish Piaractus mesopotamicus. Motor nuclei of branches of cranial nerves VII, IX and X, supplying respiratory muscles and the heart, have an overlapping distribution in the brainstem, while the Vth motor nucleus is more rostrally located. Respiration-related efferent activity in the cardiac vagus appeared to entrain the heart to ventilation. Peripheral stimulation of the cardiac vagus with short bursts of electrical stimuli entrained the heart at a ratio of 1:1 over a range of frequencies, both below and sometimes above the intrinsic heart rate. Alternatively, at higher bursting frequencies the induced f(H) was slower than the applied stimulus, being recruited by a whole number fraction (1:2 to 1:6) of the stimulus frequency. These effects indicate that respiration-related changes in f(H) in pacu are under direct, beat-to-beat vagal control. Central burst stimulation of respiratory branches of cranial nerves VII, IX and X also entrained the heart, which implies that cardiorespiratory interactions can be generated reflexly. Central stimulation of the Vth cranial nerve was without effect on heart rate, possibly because its central projections do not overlap with cardiac vagal preganglionic neurons in the brainstem. However, bursts of activity recorded from the cardiac vagus were concurrent with bursts in this nerve, suggesting that cardiorespiratory interactions can arise within the CNS, possibly by irradiation from a central respiratory pattern generator, when respiratory drive is high. PMID:19282487

  7. [Performance of recirculating aquaculture systems in the intensive farming of Pacú Piaractus mesopotamicus (Characiformes: Characidae)].

    PubMed

    Domínguez Castanedo, Omar; Martínez Espinosa, David Alberto

    2012-03-01

    An alternative to intensify fish production, reducing the environmental impact and production costs are recirculating aquaculture systems (RAS). The performance of a RAS was evaluated, as fish growth and water quality conditions, in a culture of Piaractus mesopotamicus reared for ornamental purposes. Two commercial food brands with different protein contents (18%-T1 and 28%-T2), were given to juvenile fishes during an eight weeks period. Growth was measured bi-weekly: standard length (Lp), peak height (A), weight and multiple condition factor (KM). The evaluation of water parameters included: dissolved oxygen, NH3-NH4, pH, NO2, NO3, KH carbonate hardness and PO4. NH3-N rate production was analyzed following Timmons-Ebeling model. Results demonstrated significant differences in weight only, and T2 showed a 7.5% higher value than T1; nevertheless, treatment T1 had a higher KM. In general, water quality values were suitable for growth: OD=T1: 4.23 +/- 1.23; T2: 4.13 +/- 0.86; NH3=T1: 0.02 +/- 0.02; T2: 0.06 +/- 0.10; however, pH was an exception (T1: 6.95 +/- 0.98; T2: 7.11 +/- 1.03), displaying lethal rates (<5) by the fifth week. Systems NH3 removal had a 99.4% to 100% efficiency. Final fish biomass was 22.03kg for T1 and 27.49kg for T2. We concluded that the systems were able to maintain suggested density up to the experimental fifth week. Water quality parameters remained in suitable levels, with the pH exception. Cultured fishes reached their commercial size (10cm) in eight weeks.

  8. Structural indexes and sexual maturity of tambaqui Colossoma macropomum (Cuvier, 1818) (Characiformes: Characidae) in central Amazon, Brazil.

    PubMed

    Villacorta-Correa, M A; Saint-Paul, U

    1999-11-01

    Length, weight, structural index and sexual maturity in tambaqui Colossoma macropomum were analysed. 449 specimens were obtained from the commercial fishing fleet arriving at Manaus Harbour from the floodplain areas from May 1992 to July 1993. The objective of this study is to describe changes in structural index during one hidrological cycle and to interpret them according to the water level fluctuations and to also determine the time, reproductive period and length in sexual maturity. Sex ratio in tambaqui was 1:1 however, the length of females was significantly longer than males'. Length/weight relationship was described by the expression: Pt = 0.00058*Cp2.9039. b value was significantly different from 3 which meant an alometric growth. Lower condition index values (Kn) were found from August to October at the end of receding water and dry period. The feeding index was significantly lower during the receding water and dry period. Lower hepatosomatic index values were found in December during the dry period. Fishes in lengths longer than 550 mm which were more common from September to December during the dry period, stored larger cavitary fat reserves. Fishes smaller than the standard length of 550 mm stored less fat reserves and were more common during the rising of the water and flooding period. Spawning period of tambaqui extends from September to February in a total spawning synchronized with "repiquetes" (native term used to name a sudden recending and rising of the water level). Length of tambaqui was 60.69 cm, at sexual maturity.

  9. Differential microRNA Expression in Fast- and Slow-Twitch Skeletal Muscle of Piaractus mesopotamicus during Growth

    PubMed Central

    Duran, Bruno Oliveira da Silva; Fernandez, Geysson Javier; Mareco, Edson Assunção; Moraes, Leonardo Nazario; Salomão, Rondinelle Artur Simões; Gutierrez de Paula, Tassiana; Santos, Vander Bruno; Carvalho, Robson Francisco; Dal-Pai-Silvca, Maeli

    2015-01-01

    Pacu (Piaractus mesopotamicus) is a Brazilian fish with a high economic value in pisciculture due to its rusticity and fast growth. Postnatal growth of skeletal muscle in fish occurs by hyperplasia and/or hypertrophy, processes that are dependent on the proliferation and differentiation of myoblasts. A class of small noncoding RNAs, known as microRNAs (miRNAs), represses the expression of target mRNAs, and many studies have demonstrated that miR-1, miR-133, miR-206 and miR-499 regulate different processes in skeletal muscle through the mRNA silencing of hdac4 (histone deacetylase 4), srf (serum response factor), pax7 (paired box 7) and sox6 ((sex determining region Y)-box 6), respectively. The aim of our work was to evaluate the expression of these miRNAs and their putative target mRNAs in fast- and slow-twitch skeletal muscle of pacu during growth. We used pacus in three different development stages: larval (aged 30 days), juvenile (aged 90 days and 150 days) and adult (aged 2 years). To complement our study, we also performed a pacu myoblast cell culture, which allowed us to investigate miRNA expression in the progression from myoblast proliferation to differentiation. Our results revealed an inverse correlation between the expression of the miRNAs and their target mRNAs, and there was evidence that miR-1 and miR-206 may regulate the differentiation of myoblasts, whereas miR-133 may regulate the proliferation of these cells. miR-499 was highly expressed in slow-twitch muscle, which suggests its involvement in the specification of the slow phenotype in muscle fibers. The expression of these miRNAs exhibited variations between different development stages and between distinct muscle twitch phenotypes. This work provides the first identification of miRNA expression profiles in pacu skeletal muscle and suggests an important role of these molecules in muscle growth and in the maintenance of the muscle phenotype. PMID:26529415

  10. Differential microRNA Expression in Fast- and Slow-Twitch Skeletal Muscle of Piaractus mesopotamicus during Growth.

    PubMed

    Duran, Bruno Oliveira da Silva; Fernandez, Geysson Javier; Mareco, Edson Assunção; Moraes, Leonardo Nazario; Salomão, Rondinelle Artur Simões; Gutierrez de Paula, Tassiana; Santos, Vander Bruno; Carvalho, Robson Francisco; Dal-Pai-Silva, Maeli; Dal-Pai-Silvca, Maeli

    2015-01-01

    Pacu (Piaractus mesopotamicus) is a Brazilian fish with a high economic value in pisciculture due to its rusticity and fast growth. Postnatal growth of skeletal muscle in fish occurs by hyperplasia and/or hypertrophy, processes that are dependent on the proliferation and differentiation of myoblasts. A class of small noncoding RNAs, known as microRNAs (miRNAs), represses the expression of target mRNAs, and many studies have demonstrated that miR-1, miR-133, miR-206 and miR-499 regulate different processes in skeletal muscle through the mRNA silencing of hdac4 (histone deacetylase 4), srf (serum response factor), pax7 (paired box 7) and sox6 ((sex determining region Y)-box 6), respectively. The aim of our work was to evaluate the expression of these miRNAs and their putative target mRNAs in fast- and slow-twitch skeletal muscle of pacu during growth. We used pacus in three different development stages: larval (aged 30 days), juvenile (aged 90 days and 150 days) and adult (aged 2 years). To complement our study, we also performed a pacu myoblast cell culture, which allowed us to investigate miRNA expression in the progression from myoblast proliferation to differentiation. Our results revealed an inverse correlation between the expression of the miRNAs and their target mRNAs, and there was evidence that miR-1 and miR-206 may regulate the differentiation of myoblasts, whereas miR-133 may regulate the proliferation of these cells. miR-499 was highly expressed in slow-twitch muscle, which suggests its involvement in the specification of the slow phenotype in muscle fibers. The expression of these miRNAs exhibited variations between different development stages and between distinct muscle twitch phenotypes. This work provides the first identification of miRNA expression profiles in pacu skeletal muscle and suggests an important role of these molecules in muscle growth and in the maintenance of the muscle phenotype.

  11. Responses of an Amazonian teleost, the tambaqui (Colossoma macropomum), to low pH in extremely soft water.

    PubMed

    Wood, C M; Wilson, R W; Gonzalez, R J; Patrick, M L; Bergman, H L; Narahara, A; Val, A L

    1998-01-01

    Our goal was to compare the internal physiological responses to acid challenge in an acidophilic tropical teleost endemic to dilute low-pH waters with those in nonacidophilic temperate species such as salmonids, which have been the subjects of most previous investigations. The Amazonian tambaqui (Colossoma macropomum), which migrates between circumneutral water and dilute acidic "blackwater" of the Rio Negro, was exposed to a graded low-pH and recovery regime in representative soft water (Na+ = 15, Cl- = 16, Ca2+ = 20 mumol L-1). Fish were fitted with arterial catheters for repetitive blood sampling. Water pH was altered from 6.5 (control) to 5.0, 4.0, 3.0, and back to 6.5 (recovery) on successive days. Some deaths occurred at pH 3.0. Throughout the regime, there were no disturbances of blood gases (O2 and CO2 tensions and contents) or lactate levels, and only very minor changes in acid-base status of plasma and red cells. However, erythrocytic guanylate and adenylate levels increased at pH's less than or equal to 5.0. Down to pH 4.0, plasma glucose, cortisol, and total ammonia levels remained constant, but all increased at pH 3.0, denoting a stress response. Plasma Na+ and Cl- levels declined and plasma protein concentration increased at pH 3.0, indicative of ionoregulatory and fluid volume disturbance, and neither recovered upon return to pH 6.5. Cortisol and ammonia elevations also persisted. Transepithelial potential changed progressively from highly negative values (inside) at pH 6.5 to highly positive values at pH 3.0; these alterations were fully reversible. Experimental elevations in water calcium levels drove the transepithelial potential positive at circumneutral pH, attenuated or prevented changes in transepithelial potential at low pH, and reduced Na+ and Cl- loss rates to the water during acute low-pH challenges. In general, tambaqui exhibited responses to low pH that were qualitatively similar but quantitatively more resistant than those previously

  12. [RNA/DNA ratio as an index of physiological condition of Colossoma macropomum and Piaractus branchypomus (Pisces: Characiformes) during embryonic development].

    PubMed

    Gil, Humberto; Chung, Kyung S; Lemus, Mairin; Altuve, Douglas

    2003-06-01

    We evaluated RNA/DNA ratio as an index of physiological condition during larval development of a hybrid between the fishes Colossoma macropomum (cachama) and Piaractus brachypomus (morocoto). The samples were obtained by induced reproductive technology and the eggs were maintained in acrylic conical incubator with a continuous waterflow. Embryonic development, from egg fertilization to cell division and hatch out, took 12 hours 20 minutes at 29.5 degrees C, dissolved oxygen contents of 6.0 ppm and pH 7.5. Nucleic acids quantification was determined by fluorometry with ethidium bromide and Hoechst 33258 dyes. We observed significant changes of RNA/DNA ratios during all stages of the embryonic larval development. Therefore, RNA/DNA relation is an useful technique to evaluate physiological condition in short period and could be utilized as nutritional condition and/or instantaneous growth for routine check to verify the health status in early life of cultivated species. PMID:15264559

  13. The immune system is limited by oxidative stress: Dietary selenium promotes optimal antioxidative status and greatest immune defense in pacu Piaractus mesopotamicus.

    PubMed

    Biller-Takahashi, Jaqueline D; Takahashi, Leonardo S; Mingatto, Fábio E; Urbinati, Elisabeth C

    2015-11-01

    Reactive oxygen species (ROS) are reactive molecules containing oxygen, that form as byproducts of aerobic metabolism, including immune system processes. Too much ROS may cause oxidative stress. In this study, we examined whether it can also limit the production of immune system compounds. To assess the relationship between antioxidant status and immunity we evaluated the effect of dietary supplementation with organic selenium, given at various levels for 10 days, on the antioxidant and immune system of the pacu fish (Piaractus mesopotamicus). Fish fed a diet containing 0.6 mg Se-yeast kg(-1) showed significant improvement in antioxidant status, as well as in hematological and immunological profiles. Specifically, they had the highest counts for catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), red blood cells, and thrombocytes; the highest leukocyte count (particularly for monocytes); and the highest serum lysozyme activity. There was also a positive correlation between GPx and lysozyme in this group of fish. These findings indicate that short-term supplementation with 0.6 mg Se-yeast kg(-1) reestablished the antioxidative status, allowing the production of innate components which can boost immunity without the risk of oxidative stress. This study shows a relationship between oxidative stress and immunity, and, from a practical perspective, shows that improving immunity and health in pacu through the administration of selenium could improve their growth performance. PMID:26370542

  14. The combined effect of copper and low pH on antioxidant defenses and biochemical parameters in neotropical fish pacu, Piaractus mesopotamicus (Holmberg, 1887).

    PubMed

    Sampaio, Fernanda Garcia; de Lima Boijink, Cheila; Dos Santos, Laila Romagueira Bichara; Oba, Eliane Tie; Kalinin, Ana Lúcia; Rantin, Francisco Tadeu

    2010-06-01

    Copper sulfate is widely used in aquaculture. Exposure to this compound can be harmful to fish, resulting in oxidative metabolism alterations and gill tissue damage. Pacu, Piaractus mesopotamicus, (wt = 43.4 +/- 3.35 g) were distributed in experimental tanks (n = 10; 180 l) and exposed for 48 h to control (without copper addition), 0.4Cu (0.4 mg l(-1)), 0CupH (without copper addition, pH = 5.0) and 0.4CupH (0.4 mg l(-1), pH = 5.0). In liver and red muscle, the superoxide dismutase (SOD) was responsive to the increases in the aquatic copper. The plasmatic intermediary metabolites and hematological variables in the fish of group 0.4Cu were similar to those of the control group. Conversely, the exposure to 0.4CupH caused an increase in the plasmatic lactate, number of red blood cells (RBC) and hemoglobin (Hb). Plasmatic copper concentration [Cu(p)] increased in group 0.4Cu and 0.4CupH, which is higher in group 0.4CupH, suggests an effect of water pH on the absorbed copper. Exposure to 0.4Cu and 0.4CupH resulted in a reduction in the Na(+)/K(+)-ATPase activity and an increase in metallothionein (MT) in the gills. Exposure to 0CupH caused a decrease in glucose and pyruvate concentrations and an increase in RBC, Hb, and the branchial Na(+)/K(+)-ATPase activity. These responses suggest that the fish triggered mechanisms to revert the blood acidosis, save energy and increase the oxygen uptake. MT was an effective biomarker, responding to copper in different pHs and dissolved oxygen. Combined-factors caused more significant disturbance in the biomarkers than single-factors. PMID:20213433

  15. Purification and characterization of insulin and peptides derived from proglucagon and prosomatostatin from the fruit-eating fish, the pacu Piaractus mesopotamicus.

    PubMed

    de Lima, J A; Oliveira, B; Conlon, J M

    1999-01-01

    The fruit-eating teleost fish, the pacu Piaractus mesopotamicus (Characiformes, Characidae) is classified along with the carp and the catfish in the superorder Ostariophysi. The pacu is able to survive and grow in captive conditions feeding exclusively on carbohydrates. Hormonal polypeptides in an extract of pacu Brockmann bodies were purified to homogeneity by reversed phase HPLC and their primary structures determined by automated Edman degradation. Pacu insulin contains only two substitutions, Glu-->Asp at A15 and Thr-->Ser at B24 (corresponding to B22 in mammalian insulins) compared with carp insulin. The B-chains of both insulins contain a dipeptide extension to the N-terminus and a deletion of the C-terminal residue compared with human insulin. Pacu glucagon differs from catfish glucagon by a single substitution at position 17 (Arg-->Gln. The primary structure of the 34 amino acid residue glucagon-like peptide (GLP) differs from catfish GLP only at positions 12 (Ser-->Ala) and 33 (Pro-->Gln). In common with other teleost species, the pacu expresses two somatostatin genes. Somatostatin-14, derived from preprosomatostatin-I (PSS-I), is identical to mammalian/catfish somatostatin-14. Although pacu somatostatin-II was not identified in this study, a peptide was purified that shows 67% sequence identity with residues (1-58) of catfish preprosomatostatin-II (PSS-II). This relatively high degree of sequence similarity contrasts with the fact that catfish PSS-II shows virtually no sequence identity with the corresponding PSS-II from anglerfish (Acanthopterygii) and trout (Protoacanthopterygii). A comparison of the primary structures of the islet hormones suggest that amino acid sequences may have been better conserved within the Ostariophysi than in other groups of the taxon Euteleostei that have been studied. PMID:10327603

  16. Effects of copper and cadmium on ion transport and gill metal binding in the Amazonian teleost tambaqui (Colossoma macropomum) in extremely soft water.

    PubMed

    Matsuo, Aline Y O; Wood, Chris M; Val, Adalberto L

    2005-09-30

    Metal toxicity in fish is expected to be most severe in soft waters because of the low availability of cations (particularly Ca(2+)) to out-compete the metal forms for binding sites on the gills. Natural waters in the Amazon basin are typically soft due to regional geochemistry, but few studies have focused on metal toxicity in fish native to the basin. We assessed the ionoregulatory effects of waterborne copper (Cu) and cadmium (Cd) on tambaqui (Colossoma macropomum) in extremely soft water (10 micromoll(-1) Ca(2+)). Tambaqui had a very high tolerance to Cu (50-400 microgl(-1)), as indicated by a complete lack of inhibition of Na(+) uptake and an ability to gradually recover over 6h from elevated diffusive Na(+) losses caused by Cu. The insensitivity of active Na(+) influx to Cu further supports the notion that Amazonian fish may have a unique Na(+) transport system. Addition of 5-10 mgCl(-1) of dissolved organic matter (DOM) did not prevent initial (0-3h) negative Na(+) balance in tambaqui exposed to Cu. Exposure to 40 mgCl(-1) DOM prevented Na(+) losses in tambaqui even at 400 microgl(-1) Cu, probably because most Cu was complexed to DOM. Tambaqui exposed to waterborne Cd (10-80 microgl(-1)) experienced an average of 42% inhibition in whole body Ca(2+) uptake relative to controls within 3h of exposure to the metal. Inhibition of Ca(2+) uptake increased over time and, at 24h, Ca(2+) uptake was suppressed by 51% and 91% in fish exposed to 10 and 80 microgl(-1) Cd, respectively. Previous acclimation of fish to either elevated [Ca(2+)] or elevated [DOM] proved to be very effective in protecting against acute short-term metal accumulation at the gills of tambaqui in soft water (in the absence of the protective agent during metal exposure), suggesting a conditioning effect on gill metal binding physiology. PMID:16051381

  17. Biochemical and behavioral responses of the Amazonian fish Colossoma macropomum to crude oil: the effect of oil layer on water surface.

    PubMed

    Kochhann, Daiani; Meyersieck Jardim, Manoela; Valdez Domingos, Fabíola Xochilt; Val, Adalberto Luis

    2015-01-01

    The largest Brazilian terrestrial province of petroleum mining is located at the margins of Urucu River, Amazonas. Mined crude oil is transported along 400 km across Solimões River to be refined in Manaus. Thus, the main goal of this study was to evaluate the effects of crude oil exposure on biochemical, physiological and behavioral parameters of juveniles of the Amazonian fish tambaqui (Colossoma macropomum). The toxicity of water-soluble and insoluble oil fractions and the influence of a layer formed by the oil on the water surface from low and high concentrations of crude oil were analyzed. The results showed a strong physical effect of oil at the water surface and a significant effect on fish behavior. Swimming time and response to alarm substance decreased when fish was exposed for just one day to water insoluble fraction, and remain lower after 30 days of exposure, compared to control. Chronic exposure to water insoluble fraction of the inert oil also affected these two parameters. Critical swimming velocity decreased in fish exposed to both crude and inert oil water insoluble fraction. These reductions are possibly related to a decrease in aerobic capacity. Only exposure to high concentrations of petroleum water-soluble fractions induced transient alterations of the analyzed parameters. The exposure of fish to low and high concentrations of water insoluble fraction of Urucu oil caused a reduction of responses to alarm substance, spontaneous swimming activity and swimming capacity (Ucrit), decreased activity of acetylcholinesterase, and increased activity of alkaline phosphatase. Severe hypertrophy of lamellar epithelium and extensive lamellar fusion of the gills were also observed. Overall, these results show significant behavioral and physiological changes caused by the oil layer on the water surface, which means that toxicity of petroleum produced by its chemical components is, in fact, in this fish species, enhanced by the presence of an oil phase as a

  18. Influence of the natural Rio Negro water on the toxicological effects of a crude oil and its chemical dispersion to the Amazonian fish Colossoma macropomum.

    PubMed

    Sadauskas-Henrique, Helen; Braz-Mota, Susana; Duarte, Rafael Mendonça; de Almeida-Val, Vera Maria Fonseca

    2016-10-01

    The increment in crude oil exploitation over the last decades has considerably increased the risk of polycyclic aromatic hydrocarbon (PAH) contamination to Amazonian aquatic environments, especially for the black water environments such as the Rio Negro. The present work was designed to evaluate the acute toxicity of the Urucu crude oil (CO), the chemically dispersed Urucu crude oil (CO + D), and the dispersant alone (D) to the Amazonian fish Colossoma macropomum. Acute toxicity tests were performed, using a more realistic approach, where fish were acclimated to both groundwater (GW), used as internal control, and natural Rio Negro water (RNW) and exposed to CO, CO + D and D. Then, biomarkers such as ethoxyresorufin-O-deethylase (EROD), superoxide dismutase (SOD), lipid peroxidation (LPO), serum sorbitol dehydrogenase (s-SDH) in liver, DNA damage in blood cells, and the presence of the benzo[a]pyrene-type, pyrene-type, and naphthalene-type metabolites in fish bile were assessed. Fish exposed to CO and CO + D, at both water types tested, presented increased biomarker responses and higher PAH-type metabolites in the bile. However, fish exposed to these treatments after the acclimation to RNW increased the levels of LPO, s-SDH (hepatotoxicity), DNA damage in blood cells (genotoxicity), and benzo[a]pyrene-type metabolites when compared to fish in GW. Our data suggests that some physicochemical properties of Rio Negro water (i.e., presence of natural organic matter (NOM)) might cause mild chemical stress responses in fish, which can make it more susceptible to oxidative stress following exposure to crude oil, particularly to those chemically dispersed.

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

    PubMed

    Pamplona-Basilio, M C; Kohn, A; Feitosa, V A

    2001-07-01

    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. PMID:11500767

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

    PubMed

    Ribeiro, Leila Braga; Matoso, Daniele Aparecida; Feldberg, Eliana

    2014-03-01

    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. PMID:24688290

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

    PubMed Central

    Ribeiro, Leila Braga; Matoso, Daniele Aparecida; Feldberg, Eliana

    2014-01-01

    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. PMID:24688290

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

    PubMed

    Hashimoto, Diogo Teruo; Senhorini, José Augusto; Foresti, Fausto; Martínez, Paulino; Porto-Foresti, Fábio

    2014-01-01

    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. PMID:24594674

  3. Genetic Identification of F1 and Post-F1 Serrasalmid Juvenile Hybrids in Brazilian Aquaculture

    PubMed Central

    Hashimoto, Diogo Teruo; Senhorini, José Augusto; Foresti, Fausto; Martínez, Paulino; Porto-Foresti, Fábio

    2014-01-01

    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. PMID:24594674

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

    PubMed

    Pilarski, F; Rossini, A J; Ceccarelli, P S

    2008-05-01

    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.

  5. A new species of Mymarothecium and new host and geographical records for M. viatorum (Monogenea: Dactylogyridae), parasites of freshwater fishes in Brazil.

    PubMed

    Cohen, Simone Chinicz; Kohn, Anna

    2005-11-01

    Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the "Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)", Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar. PMID:16405294

  6. Transcriptomic Characterization of Tambaqui (Colossoma macropomum, Cuvier, 1818) Exposed to Three Climate Change Scenarios.

    PubMed

    Prado-Lima, Marcos; Val, Adalberto Luis

    2016-01-01

    Climate change substantially affects biodiversity around the world, especially in the Amazon region, which is home to a significant portion of the world's biodiversity. Freshwater fishes are susceptible to increases in water temperature and variations in the concentrations of dissolved gases, especially oxygen and carbon dioxide. It is important to understand the mechanisms underlying the physiological and biochemical abilities of fishes to survive such environmental changes. In the present study, we applied RNA-Seq and de novo transcriptome sequencing to evaluate transcriptome alterations in tambaqui when exposed to five or fifteen days of the B1, A1B and A2 climate scenarios foreseen by the IPCC. The generated ESTs were assembled into 54,206 contigs. Gene ontology analysis and the STRING tool were then used to identify candidate protein domains, genes and gene families potentially responsible for the adaptation of tambaqui to climate changes. After sequencing eight RNA-Seq libraries, 32,512 genes were identified and mapped using the Danio rerio genome as a reference. In total, 236 and 209 genes were differentially expressed at five and fifteen days, respectively, including chaperones, energetic metabolism-related genes, translation initiation factors and ribosomal genes. Gene ontology enrichment analysis revealed that mitochondrion, protein binding, protein metabolic process, metabolic processes, gene expression, structural constituent of ribosome and translation were the most represented terms. In addition, 1,202 simple sequence repeats were detected, 88 of which qualified for primer design. These results show that cellular response to climate change in tambaqui is complex, involving many genes, and it may be controlled by different cues and transcription/translation regulation mechanisms. The data generated from this study provide a valuable resource for further studies on the molecular mechanisms involved in the adaptation of tambaqui and other closely related teleost species to climate change.

  7. Growth curve by Gompertz nonlinear regression model in female and males in tambaqui (Colossoma macropomum).

    PubMed

    De Mello, Fernanda; Oliveira, Carlos A L; Ribeiro, Ricardo P; Resende, Emiko K; Povh, Jayme A; Fornari, Darci C; Barreto, Rogério V; McManus, Concepta; Streit, Danilo

    2015-01-01

    Was evaluated the pattern of growth among females and males of tambaqui by Gompertz nonlinear regression model. Five traits of economic importance were measured on 145 animals during the three years, totaling 981 morphometric data analyzed. Different curves were adjusted between males and females for body weight, height and head length and only one curve was adjusted to the width and body length. The asymptotic weight (a) and relative growth rate to maturity (k) were different between sexes in animals with ± 5 kg; slaughter weight practiced by a specific niche market, very profitable. However, there was no difference between males and females up to ± 2 kg; slaughter weight established to supply the bigger consumer market. Females showed weight greater than males (± 280 g), which are more suitable for fish farming purposes defined for the niche market to larger animals. In general, males had lower maximum growth rate (8.66 g / day) than females (9.34 g / day), however, reached faster than females, 476 and 486 days growth rate, respectively. The height and length body are the traits that contributed most to the weight at 516 days (P <0.001).

  8. Transcriptomic Characterization of Tambaqui (Colossoma macropomum, Cuvier, 1818) Exposed to Three Climate Change Scenarios

    PubMed Central

    Prado-Lima, Marcos; Val, Adalberto Luis

    2016-01-01

    Climate change substantially affects biodiversity around the world, especially in the Amazon region, which is home to a significant portion of the world’s biodiversity. Freshwater fishes are susceptible to increases in water temperature and variations in the concentrations of dissolved gases, especially oxygen and carbon dioxide. It is important to understand the mechanisms underlying the physiological and biochemical abilities of fishes to survive such environmental changes. In the present study, we applied RNA-Seq and de novo transcriptome sequencing to evaluate transcriptome alterations in tambaqui when exposed to five or fifteen days of the B1, A1B and A2 climate scenarios foreseen by the IPCC. The generated ESTs were assembled into 54,206 contigs. Gene ontology analysis and the STRING tool were then used to identify candidate protein domains, genes and gene families potentially responsible for the adaptation of tambaqui to climate changes. After sequencing eight RNA-Seq libraries, 32,512 genes were identified and mapped using the Danio rerio genome as a reference. In total, 236 and 209 genes were differentially expressed at five and fifteen days, respectively, including chaperones, energetic metabolism-related genes, translation initiation factors and ribosomal genes. Gene ontology enrichment analysis revealed that mitochondrion, protein binding, protein metabolic process, metabolic processes, gene expression, structural constituent of ribosome and translation were the most represented terms. In addition, 1,202 simple sequence repeats were detected, 88 of which qualified for primer design. These results show that cellular response to climate change in tambaqui is complex, involving many genes, and it may be controlled by different cues and transcription/translation regulation mechanisms. The data generated from this study provide a valuable resource for further studies on the molecular mechanisms involved in the adaptation of tambaqui and other closely related teleost species to climate change. PMID:27018790

  9. Growth curve by Gompertz nonlinear regression model in female and males in tambaqui (Colossoma macropomum).

    PubMed

    De Mello, Fernanda; Oliveira, Carlos A L; Ribeiro, Ricardo P; Resende, Emiko K; Povh, Jayme A; Fornari, Darci C; Barreto, Rogério V; McManus, Concepta; Streit, Danilo

    2015-01-01

    Was evaluated the pattern of growth among females and males of tambaqui by Gompertz nonlinear regression model. Five traits of economic importance were measured on 145 animals during the three years, totaling 981 morphometric data analyzed. Different curves were adjusted between males and females for body weight, height and head length and only one curve was adjusted to the width and body length. The asymptotic weight (a) and relative growth rate to maturity (k) were different between sexes in animals with ± 5 kg; slaughter weight practiced by a specific niche market, very profitable. However, there was no difference between males and females up to ± 2 kg; slaughter weight established to supply the bigger consumer market. Females showed weight greater than males (± 280 g), which are more suitable for fish farming purposes defined for the niche market to larger animals. In general, males had lower maximum growth rate (8.66 g / day) than females (9.34 g / day), however, reached faster than females, 476 and 486 days growth rate, respectively. The height and length body are the traits that contributed most to the weight at 516 days (P <0.001). PMID:26628036

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

    PubMed

    Biller-Takahashi, J D; Montassier, H J; Takahashi, L S; Urbinati, E C

    2014-02-01

    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.

  11. Lethal effects of elevated pH and ammonia on juveniles of neotropical fish Colosoma macropomum (Pisces, Caracidae).

    PubMed

    de Croux, Parma; Julieta, Maria; Loteste, Alicia

    2004-01-01

    Ammonia is the main nitrogenous waste material excreted by gills, then is oxided first to nitrite and then to nitrate. The proportion of ionized-un-ionized ammonia depends on pH and temperature, when this variables increase in a solution containing ammonia the equation goes to left, so the proportion of NH3 increases and the solution becomes more toxic. The purpose of this study was to investigate the acute lethal effects of elevated pH and ammonia on tambaqui juveniles. With a constant ammonia concentration of 5.0 mg/l NH3, there was no mortality a pH of 6.0 (control) and 7.0; but was of 10-20% a pH of 8.0 and 100% at 9.0. The lethal effects of elevated pH and un-ionized ammonia should be recognized as a potential factor contributing to the variable success of tambaqui production ponds, but this species is highly resistant in comparison with other freshwater fish.

  12. Trichodina colisae (Ciliophora: Trichodinidae): new parasite records for two freshwater fish species farmed in Brazil.

    PubMed

    Jerônimo, Gabriela Tomas; Marchiori, Natália da Costa; Pádua, Santiago Benites de; Dias Neto, José; Pilarski, Fabiana; Ishikawa, Márcia Mayumi; Martins, Maurício Laterça

    2012-01-01

    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. PMID:23207983

  13. Teflubenzuron as a tool for control of trichodinids in freshwater fish: Acute toxicity and in vivo efficacy.

    PubMed

    Ikefuti, Cynthia Venâncio; Carraschi, Silvia Patrícia; Barbuio, Roberto; da Cruz, Claudinei; de Pádua, Santiago Benites; Onaka, Eduardo Makoto; Ranzani-Paiva, Maria José Tavares

    2015-07-01

    In this study we describe the anti-Trichodina effects of teflubenzuron (TFB) for Oreochromis niloticus and for Piaractus mesopotamicus. We also evaluated the acute toxicity, for both species, by using TFB in the concentrations of 700.0, 800.0, 900.0 and 1000.0 mg L(-1) and a control, without the drug. To assess the efficacy of TFB against Trichodina spp., we used the concentrations of 30.0 or 50.0 mg L(-1) for one hour exposure in tilapia, and the concentration of 30.0, 50.0 and 80.0 mg L(-1) for one hour and 50 mg L(-1) for two hours exposures in pacu. Teflubenzuron did not present significant toxicity in either species, with LC50;48h > 1000.0 mg L(-1). The drug effectiveness was observed against four identified Trichodina species: T. magna, T. heterodentata, T. compacta and T. centrostrigeata, with 87.9% parasite reduction with one hour exposure to 50.0 mg L(-1) TFB on O. niloticus and 96.1% with two hours exposure to 50.0 mg L(-1) TFB on P. mesopotamicus. Teflubenzuron is a drug with potential to be used in Brazilian aquaculture; it attends to important requirements, such as low toxicity and high efficacy in controlling Trichodina spp. infection in O. niloticus and P. mesopotamicus.

  14. Teflubenzuron as a tool for control of trichodinids in freshwater fish: Acute toxicity and in vivo efficacy.

    PubMed

    Ikefuti, Cynthia Venâncio; Carraschi, Silvia Patrícia; Barbuio, Roberto; da Cruz, Claudinei; de Pádua, Santiago Benites; Onaka, Eduardo Makoto; Ranzani-Paiva, Maria José Tavares

    2015-07-01

    In this study we describe the anti-Trichodina effects of teflubenzuron (TFB) for Oreochromis niloticus and for Piaractus mesopotamicus. We also evaluated the acute toxicity, for both species, by using TFB in the concentrations of 700.0, 800.0, 900.0 and 1000.0 mg L(-1) and a control, without the drug. To assess the efficacy of TFB against Trichodina spp., we used the concentrations of 30.0 or 50.0 mg L(-1) for one hour exposure in tilapia, and the concentration of 30.0, 50.0 and 80.0 mg L(-1) for one hour and 50 mg L(-1) for two hours exposures in pacu. Teflubenzuron did not present significant toxicity in either species, with LC50;48h > 1000.0 mg L(-1). The drug effectiveness was observed against four identified Trichodina species: T. magna, T. heterodentata, T. compacta and T. centrostrigeata, with 87.9% parasite reduction with one hour exposure to 50.0 mg L(-1) TFB on O. niloticus and 96.1% with two hours exposure to 50.0 mg L(-1) TFB on P. mesopotamicus. Teflubenzuron is a drug with potential to be used in Brazilian aquaculture; it attends to important requirements, such as low toxicity and high efficacy in controlling Trichodina spp. infection in O. niloticus and P. mesopotamicus. PMID:25913667

  15. Characterization of catalytic efficiency parameters of brain cholinesterases in tropical fish.

    PubMed

    de Assis, Caio Rodrigo Dias; Linhares, Amanda Guedes; Oliveira, Vagne Melo; França, Renata Cristina Penha; Santos, Juliana Ferreira; Marcuschi, Marina; Carvalho, Elba Verônica Matoso Maciel; Bezerra, Ranilson Souza; Carvalho, Luiz Bezerra

    2014-12-01

    Brain cholinesterases from four fish (Arapaima gigas, Colossoma macropomum, Rachycentron canadum and Oreochromis niloticus) were characterized using specific substrates and selective inhibitors. Parameters of catalytic efficiency such as activation energy (AE), k(cat) and k(cat)/k(m) as well as rate enhancements produced by these enzymes were estimated by a method using crude extracts described here. Despite the BChE-like activity, specific substrate kinetic analysis pointed to the existence of only acetylcholinesterase (AChE) in brain of the species studied. Selective inhibition suggests that C. macropomum brain AChE presents atypical activity regarding its behavior in the presence of selective inhibitors. AE data showed that the enzymes increased the rate of reactions up to 10(12) in relation to the uncatalyzed reactions. Zymograms showed the presence of AChE isoforms with molecular weights ranging from 202 to 299 kDa. Values of k(cat) and k(cat)/k(m) were similar to those found in the literature.

  16. Molecular phylogeny and ultrastructure of Myxobolus cf. cuneus, a parasite of patinga hybrid and Henneguya pseudoplatystoma, a parasite of pintado hybrid.

    PubMed

    Milanin, Tiago; Maia, Antônio Augusto Mendes; Silva, Márcia Ramos Monteiro; Carriero, Mateus Maldonado; Adriano, Edson Aparecido

    2015-09-01

    Through morphological, histopathological and ultrastructural analysis of Myxobolus cuneus Adriano, Arana et Cordeiro, 2006 and Henneguya pseudoplatystoma Naldoni, Arana, Maia, Ceccarelli, Tavares, Borges, Pozo et Adriano, 2009 were identified infecting pacu respectively (Piaractus mesopotamicus) and hybrid pintado (Pseudoplatystoma corruscans x Pseudoplatystoma reticulatum) taken from Brazilian fish farms. The present study describes 18S rDNA sequencing of Myxobolus cf. cuneus infecting the spleen of farmed patinga, a hybrid fish resulting from the crossing of P. mesopotamicus x Piaractus brachypomus, and H. pseudoplatystoma found in farmed hybrid pintado from the state of Sao Paulo, Brazil. The study also provides new details of the host-parasite interface of M. cf. cuneus, which reveal that the plasmodial wall is composed of a single membrane connected to the plasmodium ectoplasm by numerous pinocytic canals. The plasmodia also displayed asynchronous development but had disporic pansporoblasts at different developmental stages; immature and mature spores were found at different depth levels of the plasmodium. Maximum likelihood phylogenetic analysis showed that M. cf. cuneus appeared as a sister species of Henneguya pellucida Adriano, Arana et Cordeiro, 2005 in a sub-clade composed mainly of myxosporean parasites of characiforms, and that H. pseudoplatystoma clustered in a sub-clade composed of Henneguya/Myxobolus spp. parasites of siluriform fish. PMID:26204181

  17. Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent

    USGS Publications Warehouse

    Wagner, Ricardo Luiz; Makrakis, Sergio; Castro-Santos, Theodore R.; Makrakis, Maristela Cavicchioli; Dias, João Henrique Pinheiro; Belmont, René Fuster

    2012-01-01

    This paper presents results of a fishway evaluation performed at the Engenheiro Sérgio Motta Hydroelectric Power Plant (known as Porto Primavera) - CESP, Paraná River, Brazil. The evaluation was designed to quantify entry and passage proportions of 4 long-distance migratory fish species: Brycon orbignyanus (piracanjuba), Piaractus mesopotamicus (pacu), Prochilodus lineatus (curimba), and Rhinelepis aspera (cascudo-preto). Proportions finding and entering the fishway differed between species, ranged from 7.4 % (Prochilodus lineatus) to 55.4% (Piaractus mesopotamicus). Also, proportion passing was different between species, ranged from 31% (R. aspera) to 100% (Prochilodus lineatus). Fish that were marked and released within the fishway had greater failure rates than those that entered volitionally. Total time to pass ranged from 1.48 hours (Prochilodus lineatus) to 178.9 hours (R. aspera). Failure rates were greatest in the lower end of the fishway. Although some individuals of all species passed successfully, significant challenges remain to restoring connectivity of the upper Paraná River.

  18. Two new species of the tooth-carp Aphanius (Teleostei: Cyprinodontidae) and the evolutionary history of the Iranian inland and inland-related Aphanius species .

    PubMed

    Esmaeili, Hamid Reza; Teimori, Azad; Gholami, Zeinab; Reichenbacher, Bettina

    2014-01-01

    Two new species of Aphanius are described from the Kol drainage in southern Iran (Aphanius darabensis n. sp.) and the endorheic Kavir Basin in northern Iran (A. kavirensis n. sp.), and compared with eight closely related species. Aphanius darabensis n. sp. is sister to A. shirini, from which it is distinguished by molecular characters (cytochrome b) and the combination of three morphological characters: 9-18 flank bars in males (vs. 7-10), females with irregular vertical patches of brown color on the flank (vs. prominent dark brown blotches of round or irregular shape), and symmetrically-shaped triangular to trapezoid otoliths with a rostrum distinctly longer than the antirostrum (vs. quadrangular to trapezoid otoliths with short and equally sized rostrum and antirostrum). Aphanius kavirensis n. sp. is closely related to a group containing A. sophiae, A. mesopotamicus and A. pluristriatus, from which it is distinguished by cytochrome b characters and the combination of three morphological characters: females with irregularly arranged large blotches of dark brown color on the flank, short pectoral fin in both sexes (13.4-18.1% SL in males, 11.2-18.3% SL in females), and asymmetrically shaped triangular to trapezoid otoliths with a pronounced predorsal region. Our tree based on the cytochrome b data demonstrates that the Iranian inland and inland-related Aphanius species (IIRAS) form a monophyletic clade with three subclades (A. vladykovi -, A. shirini -, A. sophiae subclades). The A. sophiae subclade, which is the most diverse of the three subclades, can be further divided into three lineages (A. isfahanensis -, A. farsicus -, A. sophiae lineages). The temporal diversification of the IIRAS clade is discussed and two evolutionary groups of Aphanius are depicted. Aphanius vladykovi, together with A. shirini, A. darabensis n. sp. and A. isfahanensis characterize the "old" evolutionary group. Their divergences may have happened 10-5 m.y. ago (Late Miocene-Early Pliocene

  19. Extremely long-distance seed dispersal by an overfished Amazonian frugivore

    PubMed Central

    Anderson, Jill T.; Nuttle, Tim; Saldaña Rojas, Joe S.; Pendergast, Thomas H.; Flecker, Alexander S.

    2011-01-01

    Throughout Amazonia, overfishing has decimated populations of fruit-eating fishes, especially the large-bodied characid, Colossoma macropomum. During lengthy annual floods, frugivorous fishes enter vast Amazonian floodplains, consume massive quantities of fallen fruits and egest viable seeds. Many tree and liana species are clearly specialized for icthyochory, and seed dispersal by fish may be crucial for the maintenance of Amazonian wetland forests. Unlike frugivorous mammals and birds, little is known about seed dispersal effectiveness of fishes. Extensive mobility of frugivorous fish could result in extremely effective, multi-directional, long-distance seed dispersal. Over three annual flood seasons, we tracked fine-scale movement patterns and habitat use of wild Colossoma, and seed retention in the digestive tracts of captive individuals. Our mechanistic model predicts that Colossoma disperses seeds extremely long distances to favourable habitats. Modelled mean dispersal distances of 337–552 m and maximum of 5495 m are among the longest ever reported. At least 5 per cent of seeds are predicted to disperse 1700–2110 m, farther than dispersal by almost all other frugivores reported in the literature. Additionally, seed dispersal distances increased with fish size, but overfishing has biased Colossoma populations to smaller individuals. Thus, overexploitation probably disrupts an ancient coevolutionary relationship between Colossoma and Amazonian plants. PMID:21429923

  20. Extremely long-distance seed dispersal by an overfished Amazonian frugivore.

    PubMed

    Anderson, Jill T; Nuttle, Tim; Saldaña Rojas, Joe S; Pendergast, Thomas H; Flecker, Alexander S

    2011-11-22

    Throughout Amazonia, overfishing has decimated populations of fruit-eating fishes, especially the large-bodied characid, Colossoma macropomum. During lengthy annual floods, frugivorous fishes enter vast Amazonian floodplains, consume massive quantities of fallen fruits and egest viable seeds. Many tree and liana species are clearly specialized for icthyochory, and seed dispersal by fish may be crucial for the maintenance of Amazonian wetland forests. Unlike frugivorous mammals and birds, little is known about seed dispersal effectiveness of fishes. Extensive mobility of frugivorous fish could result in extremely effective, multi-directional, long-distance seed dispersal. Over three annual flood seasons, we tracked fine-scale movement patterns and habitat use of wild Colossoma, and seed retention in the digestive tracts of captive individuals. Our mechanistic model predicts that Colossoma disperses seeds extremely long distances to favourable habitats. Modelled mean dispersal distances of 337-552 m and maximum of 5495 m are among the longest ever reported. At least 5 per cent of seeds are predicted to disperse 1700-2110 m, farther than dispersal by almost all other frugivores reported in the literature. Additionally, seed dispersal distances increased with fish size, but overfishing has biased Colossoma populations to smaller individuals. Thus, overexploitation probably disrupts an ancient coevolutionary relationship between Colossoma and Amazonian plants.

  1. Behaviour of the oxidant scavenger metallothionein in hypoxia-induced neotropical fish.

    PubMed

    Hauser-Davis, Rachel Ann; Bastos, Frederico Freire; Dantas, Rafael Ferreira; Tobar, Santiago Alonso Leitão; da Cunha Bastos Neto, Jayme; da Cunha Bastos, Vera Lucia Freire; Ziolli, Roberta Lourenço; Arruda, Marco Aurélio Zezzi

    2014-05-01

    The pacu (Piaractus mesopotamicus) is a hypoxia-tolerant neotropical fish species. There is little or no information in this species regarding biochemical adaptations to waters with different oxygen concentrations, such as the production of reactive oxygen species and antioxidant scavengers, which might be of interest in the study of antioxidant defense mechanisms. Metallothioneins (MT) have been widely applied as biomarkers for metal exposure in fish liver, and, recently, in bile. These metalloproteins, however, have also been reported as free radical scavengers, although studies in this regard are scarce in fish. In this context, normoxic and hypoxic controlled experiments were conducted with pacu specimens and MT levels were quantified in both liver and bile. Reduced glutathione (GSH) indicative of oxidative stress, and thiobarbituric acid reactive substances (TBARS), indicative of lipid peroxidation, were also determined in liver. The results demonstrate that hypoxic fish present significantly lower metallothionein levels in liver and bile and lower reduced glutathione levels in liver, whereas lipid peroxidation was not significantly different between hypoxic and normoxic fish. The results of the present study seem to suggest that metallothioneins may actively participate in redox regulation in hypoxic fish in both bile and liver. MT levels in these organs may be temporarily suppressed, supporting the notion that down-regulation of oxidant scavengers during the oxidative burst is important in defense signaling in these adapted organisms.

  2. New host records and a checklist of fishes infected with Austrodiplostomum compactum (Digenea: Diplostomidae) in Brazil.

    PubMed

    Ramos, Igor Paiva; Franceschini, Lidiane; Zago, Aline Cristina; Zica, Erica de Oliveira Penha; Wunderlich, Alison Carlos; Carvalho, Edmir Daniel; da Silva, Reinaldo José

    2013-01-01

    This study reports the infection of fishes by Austrodiplostomum compactum metacercariae in the Chavantes reservoir, medium Paranapanema River, municipality of Ipaussu, São Paulo State, Brazil. Twenty-three fish species were analysed, and 13 were infected with A. compactum metacercariae (56.5%) in their eyes. The following six fish species are new hosts for this metacercaria: Crenicichla haroldoi (1/1), Eigenmannia trilineata (11/6), Hoplosternum littorale (11/1), Iheringichthys labrosus (17/2), Leporinus amblyrhynchus (11/1), and Piaractus mesopotamicus (3/1). These new species increase the number of Brazilian fish species infected with this parasite to 36. Based on these findings, we hypothesise that the metacercariae larval stage of the parasite has a low specificity for the second intermediate host (fish). The majority of fish species infected in Brazil belong to the Loricariidae and Cichlidae families. For the fish species with higher mean abundances in Brazil, six are non-native species, and currently, Plagioscion squamosissimus has the highest mean abundance. The majority of fish species infected with A. compactum in Brazil are concentrated in the Paraná basin, although this may be related to the distribution of researchers.

  3. Review of subtribe Singilina Jeannel, 1949, of the Middle East and Central Asia (Coleoptera, Carabidae, Lebiini)

    PubMed Central

    Anichtchenko, Alexander

    2011-01-01

    Abstract Species of the genus Singilis Rambur, 1837 (Phloeozeteus Peyron, 1856, syn. n., Agatus Motschulsky, 1845, syn. n.), occurring in the Middle East and Central Asia are reviewed, with 24 species now recognized in the region, including ten species described as new: Singilis makarovi sp. n. (Tajikistan), Singilis jedlickai sp. n. (Afghanistan), Singilis kolesnichenkoi sp. n. (Iran), Singilis kabakovi sp. n. (Afghanistan, Iran), Singilis timuri sp. n. (Uzbekistan), Singilis klimenkoi sp. n. (Iran), Singilis saeedi sp. n. (Iran), Singilis felixi sp. n. (UAE), Singilis kryzhanovskii sp. n. (Iran, Turkmenistan), and Singilis timidus sp. n. (Iran); Singilis libani (Sahlberg, 1913) is recognized as a valid species; and Singilis solskyi nom. n. is proposed as a replacement name for Agatus bicolor (Solsky, 1874, not Rambur 1837), now placed in Singilis as junior homonym. New synonymies include: Singilis cingulatus (Gebler, 1843) = Singilis jakeschi Jedlička, 1967, syn. n.; Singilis mesopotamicus Pic, 1901 = Singilis apicalis Jedlička, 1956, syn. n. A key to species is provided. Habitus and aedeagal illustrations are provided for all species. Distributional data include many new country records. PMID:22291510

  4. Bioconcentration and Acute Intoxication of Brazilian Freshwater Fishes by the Methyl Parathion Organophosphate Pesticide

    PubMed Central

    Bosco de Salles, João; Matos Lopes, Renato; de Salles, Cristiane M. C.; Cassano, Vicente P. F.; de Oliveira, Manildo Marcião; Cunha Bastos, Vera L. F.; Bastos, Jayme Cunha

    2015-01-01

    Three species of freshwater Brazilian fishes (pacu, Piaractus mesopotamicus; piavussu, Leporinus macrocephalus, and curimbatá, Prochilodus lineatus) were exposed to an acute dose of 5 ppm methyl parathion organophosphate pesticide. Three to five individuals per species were exposed, one at a time, to 40 liters tap water spiked with Folidol 600. Pesticide concentrations and cholinesterase (ChE) activities were evaluated in serum, liver, brain, heart, and muscle. The bioconcentration of methyl parathion was similar for all studied fishes. Brain tissue showed the highest pesticide concentration, reaching 80 ppm after exposure for 30 min to methyl parathion. Three to 5 hours of 5 ppm methyl parathion exposure provoked the death of all P. lineatus at 92% brain AChE inhibition, whereas fish from the other two species survived for up to 78 hours with less than 80% brain AChE inhibition. Our results indicate that acute toxic effects of methyl parathion to fish are correlated with brain AChE sensitivity to methyl paraoxon. PMID:26339593

  5. Bioconcentration and Acute Intoxication of Brazilian Freshwater Fishes by the Methyl Parathion Organophosphate Pesticide.

    PubMed

    de Salles, João Bosco; Lopes, Renato Matos; de Salles, Cristiane M C; Cassano, Vicente P F; de Oliveira, Manildo Marcião; Bastos, Vera L F Cunha; Bastos, Jayme Cunha

    2015-01-01

    Three species of freshwater Brazilian fishes (pacu, Piaractus mesopotamicus; piavussu, Leporinus macrocephalus, and curimbatá, Prochilodus lineatus) were exposed to an acute dose of 5 ppm methyl parathion organophosphate pesticide. Three to five individuals per species were exposed, one at a time, to 40 liters tap water spiked with Folidol 600. Pesticide concentrations and cholinesterase (ChE) activities were evaluated in serum, liver, brain, heart, and muscle. The bioconcentration of methyl parathion was similar for all studied fishes. Brain tissue showed the highest pesticide concentration, reaching 80 ppm after exposure for 30 min to methyl parathion. Three to 5 hours of 5 ppm methyl parathion exposure provoked the death of all P. lineatus at 92% brain AChE inhibition, whereas fish from the other two species survived for up to 78 hours with less than 80% brain AChE inhibition. Our results indicate that acute toxic effects of methyl parathion to fish are correlated with brain AChE sensitivity to methyl paraoxon. PMID:26339593

  6. Ionoregulatory Aspects of the Osmorespiratory Compromise during Acute Environmental Hypoxia in 12 Tropical and Temperate Teleosts.

    PubMed

    Robertson, Lisa M; Val, Adalberto Luis; Almeida-Val, Vera F; Wood, Chris M

    2015-01-01

    In the traditional osmorespiratory compromise, as seen in the hypoxia-intolerant freshwater rainbow trout (Oncorhynchus mykiss), the branchial modifications that occur to improve O2 uptake during hypoxia result in unfavorable increases in the fluxes of ions and water. However, at least one hypoxia-tolerant freshwater species, the Amazonian oscar (Astronotus ocellatus), shows exactly the opposite: decreased branchial flux rates of ions, water, and nitrogenous wastes during acute hypoxia. In order to find out whether the two strategies were widespread, we used a standard 2-h normoxia, 2-h hypoxia (20%-30% saturation), 2-h normoxic recovery protocol to survey 10 other phylogenetically diverse tropical and temperate species. Unidirectional influx and efflux rates of Na(+) and net flux rates of K(+), ammonia, and urea-N were measured. The flux reduction strategy was seen only in one additional species, the Amazonian tambaqui (Colossoma macropomum), which is similarly hypoxia tolerant and lives in the same ion-poor waters as the oscar. However, five other species exhibited evidence of the increased flux rates typical of the traditional osmorespiratory compromise in the trout: the rosaceu tetra (Hyphessobrycon bentosi rosaceus), the moenkhausia tetra (Moenkhausia diktyota), the bluegill sunfish (Lepomis macrochirus), the zebra fish (Danio rerio), and the goldfish (Carassius auratus). Four other species exhibited no marked flux changes during hypoxia: the cardinal tetra (Paracheirodon axelrodi), the hemigrammus tetra (Hemigrammus rhodostomus), the pumpkinseed sunfish (Lepomis gibbosus), and the Atlantic killifish (Fundulus heteroclitus). Overall, a diversity of strategies exist; we speculate that these may be linked to differences in habitat and/or lifestyle. PMID:26052633

  7. High-quality seed dispersal by fruit-eating fishes in Amazonian floodplain habitats.

    PubMed

    Anderson, Jill T; Saldaña Rojas, Joe; Flecker, Alexander S

    2009-08-01

    Seed dispersal is a critical stage in the life history of plants. It determines the initial pattern of juvenile distribution, and can influence community dynamics and the evolutionary trajectories of individual species. Vertebrate frugivores are the primary vector of seed dispersal in tropical forests; however, most studies of seed dispersal focus on birds, bats and monkeys. Nevertheless, South America harbors at least 200 species of frugivorous fishes, which move into temporarily flooded habitats during lengthy flood seasons and consume fruits that fall into the water; and yet, we know remarkably little about the quality of seed dispersal they effect. We investigated the seed dispersal activities of two species of large-bodied, commercially important fishes (Colossoma macropomum and Piaractus brachypomus, Characidae) over 3 years in Pacaya-Samiria National Reserve (Peru). We assessed the diet of these fishes during the flood season, conducted germination trials with seeds collected from digestive tracts, and quantified fruit availability. In the laboratory, we fed fruits to captive Colossoma, quantified the proportion of seeds defecated by adult and juvenile fish, and used these seeds in additional germination experiments. Our results indicate that Colossoma and Piaractus disperse large quantities of seeds from up to 35% of the trees and lianas that fruit during the flood season. Additionally, these seeds can germinate after floodwaters recede. Overexploitation has reduced the abundance of our focal fish species, as well as changed the age structure of populations. Moreover, older fish are more effective seed dispersers than smaller, juvenile fish. Overfishing, therefore, likely selects for the poorest seed dispersers, thus disrupting an ancient interaction between seeds and their dispersal agents. PMID:19466459

  8. High-quality seed dispersal by fruit-eating fishes in Amazonian floodplain habitats.

    PubMed

    Anderson, Jill T; Saldaña Rojas, Joe; Flecker, Alexander S

    2009-08-01

    Seed dispersal is a critical stage in the life history of plants. It determines the initial pattern of juvenile distribution, and can influence community dynamics and the evolutionary trajectories of individual species. Vertebrate frugivores are the primary vector of seed dispersal in tropical forests; however, most studies of seed dispersal focus on birds, bats and monkeys. Nevertheless, South America harbors at least 200 species of frugivorous fishes, which move into temporarily flooded habitats during lengthy flood seasons and consume fruits that fall into the water; and yet, we know remarkably little about the quality of seed dispersal they effect. We investigated the seed dispersal activities of two species of large-bodied, commercially important fishes (Colossoma macropomum and Piaractus brachypomus, Characidae) over 3 years in Pacaya-Samiria National Reserve (Peru). We assessed the diet of these fishes during the flood season, conducted germination trials with seeds collected from digestive tracts, and quantified fruit availability. In the laboratory, we fed fruits to captive Colossoma, quantified the proportion of seeds defecated by adult and juvenile fish, and used these seeds in additional germination experiments. Our results indicate that Colossoma and Piaractus disperse large quantities of seeds from up to 35% of the trees and lianas that fruit during the flood season. Additionally, these seeds can germinate after floodwaters recede. Overexploitation has reduced the abundance of our focal fish species, as well as changed the age structure of populations. Moreover, older fish are more effective seed dispersers than smaller, juvenile fish. Overfishing, therefore, likely selects for the poorest seed dispersers, thus disrupting an ancient interaction between seeds and their dispersal agents.

  9. Indicative and pathogenic microbiological quality of aquacultured finfish grown in different production systems.

    PubMed

    Pullela, S; Fernandes, C F; Flick, G J; Libey, G S; Smith, S A; Coale, C W

    1998-02-01

    The nature and number of indicator and pathogenic microbes in fish reared using recirculating and nonrecirculating water systems were compared. For each system, 20 samples of rainbow trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.), hybrid striped bass (Morone saxatilis x M. chrysops), and pacu (Piaractus mesopotamicus) were randomly selected and gutted, and microbial analyses were performed using AOAC procedures. Five fish were subsampled and analyzed for indicative microbial quality with 3M Petrifilm (). The general microbial quality differed significantly (P < 0.05) among the production systems, except for total coliform counts. Rainbow trout cultured in recirculating and nonrecirculating water systems had lower counts for aerobes (2.00 to 3.11 log CFU/g) (p < 0.05), than other species, whereas trout reared in a recirculating water system had significantly lower psychrotrophic numbers (0.86 to 1.85 log CFU/g). Pacu had the highest fecal coliform counts (2.74 to 3.70 log CFU/g), whereas hybrid striped bass and rainbow trout grown in nonrecirculating systems had lower fecal coliform counts (0.00 to 1.39 log CFU/g). Rainbow trout grown in a nonrecirculating system had significantly higher Escherichia coli counts (0.00 to 2.11 log CFU/g). The human bacterial pathogens Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Salmonella spp. were not isolated form the fish sampled. However, Clostridium botulinum botulinum was isolated from all the aquacultured fish sampled except pacu and tilapia grown in a recirculating aquaculture system. However, the counts were very low, ranging from 0.0 to 2.3 MPN/g. PMID:9708283

  10. Indicative and pathogenic microbiological quality of aquacultured finfish grown in different production systems.

    PubMed

    Pullela, S; Fernandes, C F; Flick, G J; Libey, G S; Smith, S A; Coale, C W

    1998-02-01

    The nature and number of indicator and pathogenic microbes in fish reared using recirculating and nonrecirculating water systems were compared. For each system, 20 samples of rainbow trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.), hybrid striped bass (Morone saxatilis x M. chrysops), and pacu (Piaractus mesopotamicus) were randomly selected and gutted, and microbial analyses were performed using AOAC procedures. Five fish were subsampled and analyzed for indicative microbial quality with 3M Petrifilm (). The general microbial quality differed significantly (P < 0.05) among the production systems, except for total coliform counts. Rainbow trout cultured in recirculating and nonrecirculating water systems had lower counts for aerobes (2.00 to 3.11 log CFU/g) (p < 0.05), than other species, whereas trout reared in a recirculating water system had significantly lower psychrotrophic numbers (0.86 to 1.85 log CFU/g). Pacu had the highest fecal coliform counts (2.74 to 3.70 log CFU/g), whereas hybrid striped bass and rainbow trout grown in nonrecirculating systems had lower fecal coliform counts (0.00 to 1.39 log CFU/g). Rainbow trout grown in a nonrecirculating system had significantly higher Escherichia coli counts (0.00 to 2.11 log CFU/g). The human bacterial pathogens Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Salmonella spp. were not isolated form the fish sampled. However, Clostridium botulinum botulinum was isolated from all the aquacultured fish sampled except pacu and tilapia grown in a recirculating aquaculture system. However, the counts were very low, ranging from 0.0 to 2.3 MPN/g.

  11. Ion and acid-base balance in three species of Amazonian fish during gradual acidification of extremely soft water.

    PubMed

    Wilson, R W; Wood, C M; Gonzalez, R J; Patrick, M L; Bergman, H L; Narahara, A; Val, A L

    1999-01-01

    Sensitivity to acid water was assessed in three species of Amazonian fish that encounter naturally acidic blackwaters to differing degrees in the wild: tambaqui (Colossoma macropomum), matrincha (Brycon erythropterum), and tamoatá (Hoplosternum littorale), in decreasing order of occurrence in blackwater. Fish were exposed to a graded reduction in water pH, from pH 6 to 5 to 4 to 3.5, followed by return to pH 6. Fish were exposed to each new pH for 24 h. During these exposures, net transfers of ions (Na+, K+, Cl-, and Ca2+) and acid-base equivalents to and from the external water were used as physiological indicators of acid tolerance. Exposure to pH 5 had a minimal effect on net ion fluxes. Significant net losses of all ions (except Ca2+) were recorded in all three species during the first few hours of exposure to pH 4. However, ion balance was usually restored within 18 h at pH 4. Exposure to pH 3.5 caused even greater ion losses in all three species and proved to be acutely lethal to tamoatá. Matrincha sustained irreversible physiological damage at pH 3.5, as ion fluxes did not recover following return to pH 6 and there was some mortality. Tambaqui suffered the least ionoregulatory disturbances at pH 3.5 and was the only species to make a full recovery on return to pH 6. In all species, there was a tendency for ammonia excretion to increase at low water pH, but even at pH 3.5, there was no significant net uptake of acid from the water. Overall, there was a strong relationship between the magnitude of ionic disturbances and the lethality of exposure to low pH. The relative insensitivity of the ionoregulatory system of tambaqui to low pH indicates that this is a feature of fish native to blackwater systems rather than one that is common to all Amazon fish.

  12. Patterns of commercial fish landings in the Loreto region (Peruvian Amazon) between 1984 and 2006.

    PubMed

    Garcia, Aurea; Tello, Salvador; Vargas, Gladis; Duponchelle, Fabrice

    2009-03-01

    Patterns of commercial fish catches over the period from 1984 to 2006 were studied in the Loreto region and in Iquitos, which is the most important town of the region and the principal fish marketplace of the Peruvian Amazon. Despite important inter-annual variations, the overall fish landings have significantly increased in the region during this period. The same three species dominated the catches during the whole period (Prochilodus nigricans, Potamorhina altamazonica and Psectrogaster amazonica), making up about 62% of the catches. However, the number of species exploited by commercial fisheries increased considerably during the 22 years of this study (from about 21 species in 1984 to over 65 in 2006), although part of the difference may be accounted for by a better identification of individual species nowadays. At the same time, the large high-valued species, such as Arapaima gigas, Colossoma macropomum and Brachyplatystoma rousseauxii, declined significantly and were replaced by smaller, short-lived and lower-valued species. Catches of the silver Arahuana (Osteoglossum bicirrhosum) also declined significantly during the studied period, strengthening recent warnings about the species' conservation status (Moreau and Coomes, Oryx 40:152-160, 2006). The relative proportions of the trophic groups (detritivores, omnivores and piscivores) remained relatively constant over the study period, but there were significant changes in the relative abundances of the species groups. The proportion of the dominant group, the Characiformes, which averaged about 81% of the catches, increased between 1984 and 2006, whereas the proportion of the Siluriformes and Perciformes remained constant. On the other hand, the proportion of Osteoglossiformes, represented only by two well known species (Arapaima gigas and Osteoglossum bicirrhosum), declined sharply during the same period. Important differences were observed between the landings of Iquitos and the landing of the whole Loreto

  13. Patterns of commercial fish landings in the Loreto region (Peruvian Amazon) between 1984 and 2006.

    PubMed

    Garcia, Aurea; Tello, Salvador; Vargas, Gladis; Duponchelle, Fabrice

    2009-03-01

    Patterns of commercial fish catches over the period from 1984 to 2006 were studied in the Loreto region and in Iquitos, which is the most important town of the region and the principal fish marketplace of the Peruvian Amazon. Despite important inter-annual variations, the overall fish landings have significantly increased in the region during this period. The same three species dominated the catches during the whole period (Prochilodus nigricans, Potamorhina altamazonica and Psectrogaster amazonica), making up about 62% of the catches. However, the number of species exploited by commercial fisheries increased considerably during the 22 years of this study (from about 21 species in 1984 to over 65 in 2006), although part of the difference may be accounted for by a better identification of individual species nowadays. At the same time, the large high-valued species, such as Arapaima gigas, Colossoma macropomum and Brachyplatystoma rousseauxii, declined significantly and were replaced by smaller, short-lived and lower-valued species. Catches of the silver Arahuana (Osteoglossum bicirrhosum) also declined significantly during the studied period, strengthening recent warnings about the species' conservation status (Moreau and Coomes, Oryx 40:152-160, 2006). The relative proportions of the trophic groups (detritivores, omnivores and piscivores) remained relatively constant over the study period, but there were significant changes in the relative abundances of the species groups. The proportion of the dominant group, the Characiformes, which averaged about 81% of the catches, increased between 1984 and 2006, whereas the proportion of the Siluriformes and Perciformes remained constant. On the other hand, the proportion of Osteoglossiformes, represented only by two well known species (Arapaima gigas and Osteoglossum bicirrhosum), declined sharply during the same period. Important differences were observed between the landings of Iquitos and the landing of the whole Loreto