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Sample records for mesopotamicus xcolossoma macropomum

  1. Chromosomal Mapping of Repetitive Sequences (Rex3, Rex6, and rDNA Genes) in Hybrids Between Colossoma macropomum (Cuvier, 1818) and Piaractus mesopotamicus (Holmberg, 1887).

    PubMed

    Ribeiro, Leila Braga; Moraes Neto, Americo; Artoni, Roberto Ferreira; Matoso, Daniele Aparecida; Feldberg, Eliana

    2017-04-01

    Some species of Characiformes are known for their high economic value, such as Colossoma macropomum and Piaractus mesopotamicus, and are used in aquaculture programs to generate hybrid tambacu (interbreeding of C. macropomum females and P. mesopotamicus males). The present work aimed to investigate the location of the Rex3 and Rex6 transposable elements in the hybrid and in the species, in addition to checking the genomic organization of the 18S and 5S rDNA in tambacu. The diploid number found for the hybrid was equal to 54 chromosomes, with heterochromatic blocks distributed mainly in the centromeric portions. The chromosomal location of the mobile elements Rex3 and Rex6 in C. macropomum, P. mesopotamicus, and in the hybrid between these species enabled knowledge expansion and the generation of data on such mobile elements. In addition, the location of such elements is not related to the distribution of ribosomal DNA sites. The mapping of the 18S rDNA was shown to be effective in cytogenetic identification of the hybrid tambacu, allowing for differentiation from the parent species and from the hybrid between C. macropomum and the other species from Piaractus (P. brachypomus).

  2. Oocyte quality of tambaqui (Colossoma macropomum) during the reproductive season.

    PubMed

    Galo, J M; Ribeiro, R P; Streit-Junior, D P; Albuquerque, D M; Fornari, D C; Roma, C F C; Guerreiro, L R J

    2015-05-01

    The study aimed to analyze the Colossoma macropomum reproductive behavior and quality of the female gametes throughout the reproductive season. The experiment was carried out in Pimenta Bueno - Rondônia State (Northern Brazil) during the reproductive season (2010-2011) using 36 females. Each sampling was performed on a 15 ± 5 days interval. Female gametes were collected by stripping and the following analyses were performed: weight of oocytes released (g); productivity index, fertilization and hatching rate. During the sampling period was verified effect (p < 0.05) of collecting time into the season for oocytes weight, productivity index and fertilization rate. Although the period 3 (December) did not differ significantly from other periods, it showed better parameters for the quality of C. macropomum oocytes.

  3. Injuries in pacu embryos (Piaractus mesopotamicus) after freezing and thawing.

    PubMed

    Neves, Patrícia Ribeiro; Ribeiro, Ricardo Pereira; Streit, Danilo Pedro; Natali, Maria Raquel M; Fornari, Darci Carlos; Santos, Alexandra Inês; Godoy, Leandro C

    2014-02-01

    Although the sperm cryopreservation of freshwater and marine teleosts has been feasible for years, the cryopreservation of some fish embryos still remains elusive. Thus, the objective of this experiment was to analyze the embryo morphology after freezing and thawing 40 embryos of Piaractus mesopotamicus immersed into methanol and ethylene glycol, both at 7, 10 and 13% plus 0.1 M sucrose for 10 min. Soon after thawing, three embryos were treated with historesin, stained with hematoxylin-eosin and analyzed under an optical microscope. From every treatment, one palette containing embryos was thawed and incubated, but none of the eggs hatched. Samples containing two embryos were immersed into 10% methanol or 10% ethylene glycol both in association with sucrose, and embryos immersed into only water or sucrose solution were frozen, processed and analyzed using scanning electron microscopy (SEM). In both cases, the control group was immersed into only water. Although the embryos had the chorion, vitello, yolk syncytial layer and blastoderm, all of them were found altered under the optical microscope and by SEM. The chorion was irregular and injured; there was no individuality in the yolk granules; the yolk syncytial layer had an irregular shape, thickness and size; the blastoderm showed injuries in the nucleus shape and sometimes was absent; the blastoderm was located in atypical areas and absent in some embryos. In conclusion, no treatment was effective in preserving the embryos, and none of the embryos avoided injury from intracellular ice formation. These morphological injuries during the freezing process made the P. mesopotamicus embryos unfeasible for hatching.

  4. 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.

  5. 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).

  6. 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

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

    PubMed

    Leão, M S L; Justo, M C N; Bueno, G W; Cohen, S C; São Clemente, S C

    2017-11-01

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

  8. Freezing injuries in the embryos of Piaractus mesopotamicus.

    PubMed

    Fornari, Darci Carlos; Ribeiro, Ricardo Pereira; Streit, Danilo Pedro; Vargas, Lauro; Barrero, Nelson M Lopera; de Moraes, Gentil Vanini

    2011-11-01

    Cryopreservation of mammal embryos has been technically feasible for many years, but morphological injuries still persist in fish embryos during cryopreservation. Thus, the objective of the present study was to describe these freezing injuries in Piaractus mesopotamicus embryos. Two hundred and twenty-five embryos were collected at the post-gastrula stage and assigned into four treatments of sucrose at 8.5, 17.0, 25.0 or 34.0% plus 9.0% methanol. The control was prepared with distilled water only. The gradual decrease in the temperature was 0.5°C/min. After the seeding stage, the fish embryos were stored in liquid nitrogen at -33°C. Thereafter, they were thawed for evaluating per cent hatching, and the samples collected from every treatment were submitted to scanning electron microscopy for morphological analysis. The micrographic images showed that there was substantial alterations in embryo morphology under the highest concentrations of sucrose. These solutions did not prevent the formation of ice crystals, which lead to deformities and killed the embryos, but the observed reduced level of morphological structure in these embryos when treated with 17.0% sucrose plus 9.0% methanol is a compelling argument for additional studies.

  9. [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.

  10. High genetic diversity and connectivity in Colossoma macropomum in the Amazon basin revealed by microsatellite markers.

    PubMed

    Fazzi-Gomes, Paola; Guerreiro, Sávio; Palheta, Glauber David Almeida; Melo, Nuno Filipe Alves Correa de; Santos, Sidney; Hamoy, Igor

    2017-02-06

    Colossoma macropomum is the second largest scaled fish of the Amazon. It is economically important for commercial fisheries and for aquaculture, but few studies have examined the diversity and genetic structure of natural populations of this species. The aim of this study was to investigate the levels of genetic variability and connectivity that exist between three natural populations of C. macropomum from the Amazon basin. In total, 247 samples were collected from the municipalities of Tefé, Manaus, and Santarém. The populations were genotyped using a panel of 12 multiplex microsatellite markers. The genetic diversity found in these populations was high and similar to other populations described in the literature. These populations showed a pattern of high gene flow associated with the lack of a genetic structure pattern, indicating that the number of migrants per generation and recent migration rates are high. The values of the FST, RST, and exact test of differentiation were not significant for pairwise comparisons between populations. The Bayesian population clustering analysis indicated a single population. Thus, the data provide evidence for high genetic diversity and high gene flow among C. macropomum populations in the investigated region of the Amazon basin. This information is important for programs aiming at the conservation of natural populations.

  11. High genetic diversity and connectivity in Colossoma macropomum in the Amazon basin revealed by microsatellite markers

    PubMed Central

    Fazzi-Gomes, Paola; Guerreiro, Sávio; Palheta, Glauber David Almeida; de Melo, Nuno Filipe Alves Correa; Santos, Sidney; Hamoy, Igor

    2017-01-01

    Abstract Colossoma macropomum is the second largest scaled fish of the Amazon. It is economically important for commercial fisheries and for aquaculture, but few studies have examined the diversity and genetic structure of natural populations of this species. The aim of this study was to investigate the levels of genetic variability and connectivity that exist between three natural populations of C. macropomum from the Amazon basin. In total, 247 samples were collected from the municipalities of Tefé, Manaus, and Santarém. The populations were genotyped using a panel of 12 multiplex microsatellite markers. The genetic diversity found in these populations was high and similar to other populations described in the literature. These populations showed a pattern of high gene flow associated with the lack of a genetic structure pattern, indicating that the number of migrants per generation and recent migration rates are high. The values of the FST, RST, and exact test of differentiation were not significant for pairwise comparisons between populations. The Bayesian population clustering analysis indicated a single population. Thus, the data provide evidence for high genetic diversity and high gene flow among C. macropomum populations in the investigated region of the Amazon basin. This information is important for programs aiming at the conservation of natural populations. PMID:28170026

  12. [Effects of parasitism on gill structure of Leporinus macrocephalus Garavello and Britsk, 1988 (Anastomidae) and Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes:Characidae)].

    PubMed

    Schalch, Ergio H C; de Moraes, Flávio R; de Moraes, Julieta R E

    2006-01-01

    This work described the lesions caused in different species of fish by gill parasites from fee-fishing at Guariba, State of São Paulo. The research was developed from april, 1997 to march to 1999, seeking to verified the kind tissues lesions from fish. Of these, forty and seven were Leporinus macrocephalus and fifty and five Piaractus mesopotamicus. About 87.2% of the L. macrocephalus, and 58.1% of the P. mesopotamicus were sponged by several species of parasites. The parasite most abundant in L. macrocephalus was Piscinoodinium pillulare, while monogenean, Trichodina sp and myxosporidian infected P. mesopotamicus. Severe gill lesions have been observed in L. macrocephalus and P. mesopotamicus caused by monogenean, P. pillulare e Trichodina sp. parasitism, such as intersticial hemorrhage, sub-epithelium edema, inflammation, epitelial hiperplasy in filaments and lamina, proliferation of mucosal cells and laminar fusion.

  13. Differential expression of a retrotransposable element, Rex6, in Colossoma macropomum fish from different Amazonian environments

    PubMed Central

    Barbosa, Cassiane Martins; Mareco, Edson Assunção; Silva, Maeli Dal Pai; Martins, Cesar; Alves-Costa, Fernanda Antunes

    2014-01-01

    Transposable elements (TEs) are DNA sequences that have the ability to move and replicate within the genomes. TEs can be classified according to their intermediates of transposition, RNA (retrotransposons) or DNA. In some aquatic organisms, it has been observed that environmental factors such as pH, temperature and pollution may stimulate differential transcription and mobilization of retrotransposons. In light of this information, the present study sought to evaluate the expression of Rex6 TE transcripts in Colossoma macropomum, which is a very commercially exploited fish in Brazil. In order to establish a comparative analysis using real-time PCR, the samples were collected from Amazonian rivers with different physical and chemical characteristics (distinguished by clear water and black water). Quantitative RT-PCR analyses revealed a differential pattern of expression between tissues collected from different types of water (clear and black waters). When it came to the hepatic and muscle tissues sampled, the levels of Rex6 transcripts were significantly different between the two Amazonian water types. These results suggest that environmental conditions operate differently in the regulation of Rex6 transcription in C. macropomum, results which have implications in the reshaping of the genome against environmental variations. PMID:25089227

  14. 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.

  15. Acute aerocystitis in Piaractus mesopotamicus: participation of eicosanoids and pro-inflammatory cytokines.

    PubMed

    Claudiano, Gustavo da Silva; Petrillo, Thalita R; Manrique, Wilson G; Castro, Marcello P; Loureiro, Bruna A; Marcusso, Paulo F; Belo, Marco A A; Moraes, Julieta R E; de Moraes, Flávio Ruas

    2013-05-01

    A total of 360 pacus (Piaractus mesopotamicus) were used to study vascular permeability (VP) and inflammatory cell component (CC) in induced aerocystitis in P. mesopotamicus through inoculation of inactivated Aeromonas hydrophila, and the effect of steroidal and nonsteroidal anti-inflammatory drugs. It was observed that after inoculation of A. hydrophila, the maximum VP occurred 180 min post-stimulus (MPS). Pretreatment with anti-inflammatory drugs inhibited VP, and the inhibitory effect of dexamethasone was seen earlier than the effects caused by meloxicam and indomethacin. Inoculation of the bacterium caused a gradual increase in the accumulation of cells, which reached a maximum 24 h post-stimulus (HPS). Pretreatment with dexamethasone, indomethacin and meloxicam reduced the accumulation of lymphocytes, thrombocytes, granulocytes and macrophages. There was no significant difference between the different doses of the drugs tested. The results suggest that eicosanoids and pro-inflammatory cytokines participate in chemical mediation in acute inflammation in pacus.

  16. 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

  17. 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

  18. Impacts of stocking on the genetic diversity of Colossoma macropomum in central Amazon, Brazil.

    PubMed

    de Queiroz, C A; Sousa, N R; da Silva, G F; Inoue, L A K A

    2016-04-07

    Tambaqui (Colossoma macropomum) is the main fish species farmed on a commercial scale in northern Brazil. In view of the current scenario of Brazilian aquaculture, studies on the genetic improvement and reproductive management of captive tambaqui are crucial in identifying the genetic variability of broodstocks and devising management practices. Genetic diversity of three tambaqui broodstocks in western Amazon was evaluated using molecular markers. Fin samples were collected from 89 fish; 38 from Balbina, 30 from a hatchery in Rio Preto da Eva, and 21 from the experimental farm of the Federal University of Amazonas (UFAM). Ten primers were used for the analysis of diversity and genetic structure. Of the 152 bands produced, 146 were polymorphic. The proportion of polymorphic loci showed little variation among the three stocks. The lowest and highest rates were found in the Rio Preto da Eva (80.92%) and Balbina (85.53%) stocks, respectively. Heterozygosity (H) and Shannon (I) indices were similar among the stocks; the lowest values were found in Balbina (H = 0.279 and I = 0.419), and the highest in UFAM (H = 0.294 and I = 0.439). Following analysis of the genetic structure and relationship, the sample was divided into two groups, with the Balbina stock clearly deviating from the others. The results suggest that, to increase genetic variability, molecular information may be used instead of replacement of wild breeders. The groups characterized here can be used in genetic improvement programs with other tambaqui broodstocks from different areas of South America.

  19. 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.

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

    PubMed

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

    2017-01-01

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

  1. Two sides of a coin: Effects of climate change on the native and non-native distribution of Colossoma macropomum in South America

    PubMed Central

    Lopes, Taise M.; Bailly, Dayani; Almeida, Bia A.; Santos, Natália C. L.; Gimenez, Barbara C. G.; Landgraf, Guilherme O.; Sales, Paulo C. L.; Lima-Ribeiro, Matheus S.; Cassemiro, Fernanda A. S.; Rangel, Thiago F.; Diniz-Filho, José A. F.; Agostinho, Angelo A.; Gomes, Luiz C.

    2017-01-01

    Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in Paraná River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions. PMID:28654663

  2. Two sides of a coin: Effects of climate change on the native and non-native distribution of Colossoma macropomum in South America.

    PubMed

    Lopes, Taise M; Bailly, Dayani; Almeida, Bia A; Santos, Natália C L; Gimenez, Barbara C G; Landgraf, Guilherme O; Sales, Paulo C L; Lima-Ribeiro, Matheus S; Cassemiro, Fernanda A S; Rangel, Thiago F; Diniz-Filho, José A F; Agostinho, Angelo A; Gomes, Luiz C

    2017-01-01

    Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in Paraná River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions.

  3. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

    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.

  5. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Fish sperm subpopulations: Changes after cryopreservation process and relationship with fertilization success in tambaqui (Colossoma macropomum).

    PubMed

    Gallego, V; Cavalcante, S S; Fujimoto, R Y; Carneiro, P C F; Azevedo, H C; Maria, A N

    2017-01-01

    Fish tambaqui (Colossoma macropomum) is the native Brazilian fish with the highest agricultural production under intensive aquaculture in South America. However, the decrease in the genetic variability in fish farms has become necessary the improvement of cryopreservation process through new statistical studies of spermatozoa (like subpopulation studies). The evaluation of the kinetic data obtained with a computer-assisted sperm analysis system, applying a two-step cluster analysis, yielded in tambaqui three different subpopulations in fresh sperm: SP1, considered as a slow nonlinear subpopulation; SP2, considered as a fast nonlinear subpopulation, and finally; SP3, considered as a fast linear subpopulation. For cryopreserved sperm, the cluster analysis yielded only two sperm subpopulations: SP1', considered as a slow nonlinear subpopulation and SP2', which seemed to be an intermediate subpopulation (showing medium motility and velocity values) merged from SP2 and SP3 obtained from fresh sperm. Coefficients of correlation (r) and determination (r(2)) between the sperm subpopulations from fresh sperm and the fertilization rates were calculated, and SP2 and SP3 (the fast-spermatozoa subpopulations) showed a high-positive correlation with the fertilization rates (r = 0.93 and 0.79, respectively). In addition, the positive significant correlations found in curvilinear velocity (r = 0.78), straight line velocity (r = 0.57), and average velocity (r = 0.75) indicate that sperm kinetic features seem to be a key factor in the fertilization process in tambaqui, as occur in other fish species.

  7. Characterization of a new strain of Aeromonas dhakensis isolated from diseased pacu fish (Piaractus mesopotamicus) in Brazil.

    PubMed

    Carriero, M M; Mendes Maia, A A; Moro Sousa, R L; Henrique-Silva, F

    2016-11-01

    This study provides a detailed description and characterization of a strain of Aeromonas dhakensis isolated from a diseased juvenile Piaractus mesopotamicus obtained from the fish farm of the National Center for Continental Fish Research and Conservation (CEPTA/ICMBio), in the state of São Paul, Brazil. Biochemical tests using the VITEK 2 automated bacterial identification system identified the isolate to genus level; however, further molecular analysis of the 16S rRNA, gyrB and rpoD genes showed that the strain belonged to the species A. dhakensis. As expected, the isolated A. dhakensis strain was resistant to ampicillin and ampicillin/sulbactam, as resistance to ampicillin is a typical characteristic of the genus Aeromonas. Resistance to cefoxitin and meropenem was also observed, but the strain was susceptible to most of the tested antibiotics. The isolated strain of A. dhakensis caused acute haemorrhagic septicaemia in experimentally infected P. mesopotamicus, with a fifty per cent lethal dose of 1.14 × 10(5)  CFU/fish. This is the first report of the occurrence of an A. dhakensis strain causing an infection in a fish species of South America, providing important epidemiologic data relating to this important pathogenic species. © 2016 John Wiley & Sons Ltd.

  8. Acute exposure of a glyphosate-based herbicide affects the gills and liver of the Neotropical fish, Piaractus mesopotamicus.

    PubMed

    Shiogiri, Natália S; Paulino, Marcelo G; Carraschi, Silvia P; Baraldi, Flávia G; da Cruz, Claudinei; Fernandes, Marisa Narciso

    2012-09-01

    The aim of this study was to determine the acute toxicity of Roundup(®) Ready (RR) in Piaractus mesopotamicus, and evaluate the effects on the morphology of the gills and liver of exposed surviving fish. Fish were exposed to 3.0, 3.5, 4.0 and 4.5mgL(-1) of glyphosate, and the LC(50);48h was estimated at 3.74±0.2mgL(-1). Gill histopathology was rare, and the activity of Na(+)/K(+)-ATPase enzyme did not change, suggesting normal function. However, the damage to the liver was classified as moderate to severe. Cytoplasmic vacuolization, lipid accumulation, nuclear and cellular membrane alterations and glycogen depletion were found in the liver, suggesting a reduction in the liver function. The glyphosate in the RR formulation was classified as moderately toxic for P. mesopotamicus, and the severe damage in the liver may affect the detoxification and/or tissue repair process and contribute to fish death.

  9. Linking hematological, biochemical, genotoxic, and behavioral responses to crude oil in the Amazon fish Colossoma macropomum (Cuvier, 1816).

    PubMed

    Kochhann, Daiani; de Azevedo Brust, Sandra Maristher; Domingos, Fabíola Xochilt Valdez; Val, Adalberto Luis

    2013-08-01

    Despite safety protocols, crude oil extraction and transportation in the Amazon basin has a potential for inadvertent oil spills, which can impact aquatic organisms in local rivers. The objective of this study was to assess the effects of crude oil on juvenile Amazonian fish tambaqui, Colossoma macropomum, at various biological levels. Furthermore, the effect of crude oil on response to alarm substance, an important communication system in fish, was reported for the first time. Fish exposed to crude oil showed a 90 % decrease in their response to alarm substance and a 60 % decrease in swimming activity relative to control fish. Basic hematology was not affected, although an increase of 200 % of DNA damage and an increase of GST activity were observed in animals exposed to crude oil. Inverse correlations were found between genotoxicity end points and behavioral parameters, suggesting that genotoxic end points can also reflect behavioral changes.

  10. SHORT-COMMUNICATION Validation of reference genes for real-time quantitative PCR in tambaqui (Colossoma macropomum).

    PubMed

    Nascimento, A R; Silva, G F; Gualberto, G F; Almeida, F L

    2016-12-23

    Tambaqui, Colossoma macropomum, is the main native freshwater fish in Brazilian aquaculture. Therefore, intensive research pressure has been applied to the species to support new technologies for tambaqui farming. Molecular biology represents a tool that can be used to investigate every field of applied biology, from fish physiology to the effects of climate change. Based on the importance of reference genes for the relative or absolute quantification of gene transcripts, we cloned and sequenced three candidate reference genes in tambaqui (18S ribossomal RNA - 18s, glyceraldehyde-3-phosphate dehydrogenase - gapdh, and actin beta - β-actin), and validated a set of primers for each gene for use in real-time quantitative PCR. The results were evaluated by RefFinder, which indicated that β-actin is the most suitable reference gene for tambaqui among those studied, followed by 18s.

  11. 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.

  12. Acute toxicity by water containing hexavalent or trivalent chromium in native Brazilian fish, Piaractus mesopotamicus: anatomopathological alterations and mortality.

    PubMed

    Castro, Marcello Pardi; de Moraes, Flávio Ruas; Fujimoto, Rodrigo Yudi; da Cruz, Claudinei; Belo, Marco Antonio de Andrade; de Moraes, Julieta Rodini Engrácia

    2014-02-01

    This study evaluated the toxicity of hexavalent and trivalent compounds of chromium to the pacu, Piaractus mesopotamicus, in acute exposures of 96 h through mortality and histopathological responses. Hexavalent potassium dichromate was more toxic than trivalent compounds of chromium chloride, chromium oxide and chromium carbochelate. Sufficient mortalities occurred only with potassium dichromate to yield an LC50 value at 124.2 mg L(-1). Hexavalent chromium caused reversible and irreversible lesions, which may affect organ functionality. Histopathological evaluation showed that trivalent chromium caused lesions of lower severity. Pacu subjected to different concentrations of chromium carbochelate showed no histopathological changes in the kidneys, liver, skin and gills, being similar to those of the control fish. Among the three sources of Cr(3+), only chromium chloride at 200 mg L(-1) resulted in mortality, which reached 100 % within the first 18 h. These findings confirm that trivalent chromium, when administered within recommended levels, may be used safely in aquaculture.

  13. Antiparasitic activity, histopathology and physiology of Colossoma macropomum (tambaqui) exposed to the essential oil of Lippia sidoides (Verbenaceae).

    PubMed

    Soares, Bruna Viana; Neves, Lígia Rigôr; Ferreira, Drielly Oliveira; Oliveira, Marcos Sidney Brito; Chaves, Francisco Célio Maia; Chagas, Edsandra Campos; Gonçalves, Raissa Alves; Tavares-Dias, Marcos

    2017-01-30

    In vivo and in vitro antiparasitic activity of the essential oil of Lippia sidoides and blood and histological alterations were assessed in Colossoma macropomum (tambaqui). Essential oil concentrations of 10, 20, 40, 80, 160 and 320mg/L were assayed in vitro against monogenoideans Anacanthorus spathulatus, Notozothecium janauachensis and Mymarothecium boegeri from fish gills. Lippia sidoides essential oil concentrations of 320 and 160mg/L were 100% effective against monogenoideans in 10min and 1h of exposure, respectively. However, the effectiveness of 100% concentrations of 80mg/L and 40mg/L occurred in 3 and 6h, respectively. In the in vivo tests, juvenile fish were submitted to 60min of baths with 10mg/L and 15min of baths with 20mg/L of the essential oil of L. sidoides. These therapeutic baths were not efficient against Ichthyophthirius multifiliis, and monogenoideans present in the gills of C. macropomum. In addition, 10 and 20mg/L of the essential oil of L. sidoides caused an anesthetic effect on the fish and did not influence total glucose and protein plasma levels; however, it decreased the number of total erythrocytes in fish exposed to the higher concentration of this essential oil. Severe alterations and irreversible damage were observed in the fish gills just after L. sidoides essential oil baths and after 24h of recovery. The most recurrent lesions found were hyperplasia and fusion of the lamellar epithelium, vasodilation, detachment of the gill epithelium and lamellar aneurism, epithelial breakdown with hemorrhage, congestion, edema and necrosis, proliferation of the mucous cells and chloride cells and lamellar hypertrophy. Therefore, since the essential oil of L. sidoides has in vitro antiparasitic activity and low concentrations of it have shown toxic effects, the bioactive potential of its main chemical components should be investigated, as well as more efficient forms of its administration in therapeutic baths in order to eliminate fish parasites

  14. 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

    2016-08-18

    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.

  15. The effect of cryoprotectant agents on DNA methylation patterns and progeny development in the spermatozoa of Colossoma macropomum.

    PubMed

    de Mello, Fernanda; Garcia, Juliana Saraiva; Godoy, Leandro C; Depincé, Alexandra; Labbé, Catherine; Streit, Danilo P

    2017-05-01

    DNA methylation patterns are inherited from parents and are imperative for proper embryonic development; however, alterations in these patterns can compromise fertilization and development into a fully functioning adult animal because DNA methylation is part of a complex program of gene transcription. In this study, we investigated the impact of cryoprotectant agents (CPAs) on DNA methylation patterns in spermatozoa and the consequences on embryonic development and the survival rate of progeny. Global methylation was assessed by enzymatic reactions in Colossoma macropomum spermatozoa that were cryopreserved using dimethylsulfoxide, dimethylformamide, methanol, ethyl glycol and glycerol as CPAs. Fertilization was carried out to evaluate survival rates and abnormalities in embryonic development upon treatment with each of the CPAs. Fresh semen served as the control. Our results indicated that, compared to the control group, spermatozoa cryopreservation decreased the fertilization rate and delayed embryonic development from the midblastula stage. Furthermore, spermatozoa cryopreserved in all CPAs had lower methylation levels and exhibited more delays and abnormalities during embryonic development than did fresh semen. Methanol resulted in fertilization, hatching rates and embryonic development that were closer to the control but had lower methylation levels. In conclusion, ours results show significant alterations on spermatozoa DNA methylation patterns caused by CPAs that are used in the semen cryopreservation process. DNA methylation pattern alterations affected the viability of progeny (r=0.48); however, these effects can be minimized by choosing the CPA that will compose the freezing solution. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. 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

  17. The interaction of methyl-parathion with serum and albumin of the neo-tropical fish Piaractus mesopotamicus.

    PubMed

    Silva, Dilson; Cortez-Moreira, Madelayne; Cunha Bastos, Vera L F; Cunha Bastos, Jayme; Martins Cortez, Célia

    2010-01-01

    The interaction of methyl-parathion with serum and albumin of pacu, Piaractus mesopotamicus, was studied, using the fluorescence quenching technique. Pacu is a neo-tropical fish specie inhabitant of rivers from western regions of Brazil. Methyl-parathion (O,O-dimethyl O-p-nitrophenyl phosphorothioate) is an organophosphorous pesticide still used in agriculture and fish farming in many countries. The quenching of fluorescence can be mathematically expressed by the Stern-Volmer equation to calculate quenching constants. Stern-Volmer curves analysis is able to give important information about the pesticide-albumin interaction. Our results showed that the serum quenching reached 10% when the molar ratio of pesticide/albumin was about 7:1 for the three temperatures of the experiment. For the pure albumin quenching of 10%, methyl-parathion concentrations were 6, 7 and 9 times higher than albumin at 20, 25 and 30 degrees C, respectively. The calculated Stern-Volmer constants at 25 degrees C were 9.73x10(3)(+/-4.9x10(2))M(-1) for serum and 9.20x10(3)(+/-2.0x10(2))M(-1) for albumin. It was observed that albumin quenching is the phenomenon contributing to the quenching of the pacu serum fluorescence for methyl-parathion concentration lower than 10microM, suggesting that the protein is the most important carrier for the pesticide in serum.

  18. Morphological, histochemical and morphometric study of the myotomal muscle tissue of the pacu (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei).

    PubMed

    Dal Pai, V; Pai-Silva, M D; Carvalho, E D; Fujihara, C Y; Gregório, E A; Curi, P R

    2000-10-01

    Histochemical, ultrastructural and morphometric methods were used to study growth patterns of red, pink and white muscle fibres and their relation to body weight and total length in the fast-growing freshwater fish Piaractus mesopotamicus Holmberg. The correlations amongst body weight, body length and diameter of red, pink and white fibres were low. From 10-15 to 40-50 cm, body weight increased 102.7 times, while the diameter of each type of fibre increased by factors of 0.94, 0.74 and 0.70, respectively. Muscle fibres revealed different morphological and histochemical stages of maturation. The frequencies of < 20 microns fibres of red, pink and white muscle tissue in the youngest and oldest classes were 64.5 and 11.0, 38.2 and 7.7 and 24.0 and 1.4%, respectively. In 30-40 cm fish, the frequency of < 20 microns fibres in the red and pink tissue was 24.5 and 25.5%, while in the white tissue it was 11.5%. During sexual maturity (40-50 cm), the recruitment of < 20 microns fibres in white muscle was 1.4%. Muscle fibres of this species showed continuous growth by both hyperplastic and hypertrophic mechanisms, and hyperplasia was particularly active in the juvenile phase.

  19. Myxobolus sp. and Henneguya sp. (Cnidaria: Myxobolidae) natural co-infection in the kidney of Piaractus mesopotamicus (Characiformes: Serrasalmidae).

    PubMed

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

    2017-08-05

    This study evaluated the myxozoan infection and histopathology of the kidney of freshwater fish Piaractus mesopotamicus from intensive fish farming in Brazil. A total of 55 fish were examined for myxozoan infection. Infected organs were processed by usual histology and stained with hematoxylin-eosin (H&E) and Ziehl-Neelsen (ZN). From the total of 55 fish analyzed, 47 (85.45%) presented myxospores, being 9.09% (5/55) only with Myxobolus sp., 5.45% (3/55) only with Henneguya sp., and 70.91% (39/55) presenting both parasites. The presence of myxospores was associated with histological alterations in both stromal and renal parenchyma. Myxospores were found mostly in the peritubular interstitial tissue and in low intensity in the glomerulus which caused nuclear hypertrophy and loss of Bowman space. An increase in the glomerular tuft and a reduction in the lumen of the collector tubules were also observed, besides the high number of melanomacrophage cells in the glomerulus. This study reports for the first time detection of myxozoan mixed infection in one organ of pacu and discuss the possible transportation of myxospores in the circulating blood.

  20. 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. © 2016 John Wiley & Sons Ltd.

  1. Changes on physiological parameters of tambaqui (Colossoma macropomum) fed with diets supplemented with Amazonian fruit Camu camu (Myrciaria dubia).

    PubMed

    Aride, P H R; Oliveira, A M; Batista, R B; Ferreira, M S; Pantoja-Lima, J; Ladislau, D S; Castro, P D S; Oliveira, A T

    2017-09-21

    The physiological responses of juvenile tambaqui (Colossoma macropomum) fed commercial feed supplemented with different concentrations of camu camu (Myrciaria dubia) were evaluated. The design was completely randomized, with treatments arranged in a factorial design with three proportions of camu camu (15%, 30% and 45%) and a control treatment (100% commercial diet), with four replicates per treatment. A total of 96 tambaqui specimens were used, with a mean initial weight of 11.69 ± 2.68 g and a mean length of 7.06 ± 0.44 cm. After 30 days, hematological parameters, metabolic variables, growth and fish swimming performance were evaluated. The different proportions of camu camu in the diet did not cause significant changes to the tambaqui's hematological parameters during the feeding period, except for hemoglobin (Hb) concentration and mean corpuscular hemoglobin concentration (MCHC) after the 30th day, and hematocrit (Ht) after the swimming stress test, which increased significantly (p < 0.05). The significant increases in metabolic variables, such as cortisol, glucose, proteins and triglycerides, and in hematologic variables after the Ucrit test reflect, respectively, biochemical adaptations for maintenance of the energy mobilization process and a regulatory necessity in tissue oxygen demand during intense exercise. Fish fed 15% and 30% camu camu gained the most weight and achieved the best swimming performance, respectively. The results for camu camu concentrations above 30% suggest a saturation of its intrinsic properties in the diet at this level and a loss of nutrients from the commercial feed replaced by the fruit, reducing productive performance and nutritional assimilation.

  2. Atrazine levels in the Jaboticabal water stream (São Paulo State, Brazil) and its toxicological effects on the pacu fish Piaractus mesopotamicus.

    PubMed

    Santos, Edson Aparecido dos; Cruz, Claudinei da; Carraschi, Silvia Patrícia; Marques Silva, José Roberto; Grossi Botelho, Rafael; Velini, Edivaldo Domingues; Pitelli, Robinson Antonio

    2015-03-01

    The aim of this study was to determine the environmental concentration of atrazine (ATZ) in five streams located in the north of São Paulo state (Brazil) and evaluate its toxicological impact on young specimens of the pacu fish Piaractus mesopotamicus. Samples of water were collected on three occasions between 2010 and 2011, corresponding to periods signifying the beginning, middle, and end of rain season. ATZ levels were estimated by a high-performance liquid chromatography coupled with a mass spectrometry (HPLC-MS/MS) triple quadrupole. Later, the quotient of environmental risk (QR) was determined based on the medium lethal concentration (LC50 48 h), non-observable effect concentration (NOEC), and the estimated environmental concentration (EEC) of ATZ detected in the environment. Histological changes in gills and liver were also studied, along with the brain activity of the enzyme acetylcholinesterase (AChE). The highest concentration of ATZ measured was 10.4 μg L(-1). The ATZ LC50 (48 h) for young P. mesopotamicus was 24.46 mg L(-1) and the QR was classified as "safe". Although the QR indicated that ATZ could be safe for the tested species, it caused many histological alterations in the liver and gills of the exposed specimens, and an increase in the AChE levels.

  3. Antioxidant defenses and biochemical changes in pacu (Piaractus mesopotamicus) in response to single and combined copper and hypoxia exposure.

    PubMed

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

    2008-01-01

    The effect of combined-factors (hypoxia+copper) on the biochemical parameters and antioxidant defenses were studied in the neotropical fish Piaractus mesopotamicus. Fish were exposed for 48 h to 0.4 mg Cu(2+) L(-1) (0.4Cu), hypoxia=50 mm Hg (Hpx), and 0.4 mg Cu(2) L(-1)+hypoxia=50 mm Hg (0.4CuHpx). The exposure to 0.4Cu increased the reactive oxygen species (ROS) in the liver, accompanied by increases in superoxide dismutase (SOD) and decreases in catalase (CAT) activity, showing the influence of copper in this protection. The exposure to Hpx decreased the activity of glutathione peroxidase (GSH-Px) and CAT. Exposure to a combined-factor caused an increase in the ROS production followed by an increase in SOD and a decrease in GSH-Px and CAT. At 0.4Cu, fish presented a reduction in CAT, while in Hpx decreases in SOD, CAT and GSH-Px were observed in red muscles. Single-factors were insufficient to cause ROS production. In combined-factors, increased ROS formation and decreased SOD, CAT and GSH-Px were observed. RBC increased in all groups, but only under combined-factors was there an increase in hemoglobin. Copper plasma concentration increased in groups exposed to copper. Na(+)/K(+)-ATPase activity in gills decreased in 0.4Cu and 0.4CuHpx, and increased in Hpx. Metallothionein concentration in gills increased under combined-factors. Combined-factors caused significant disturbances in the antioxidant defenses and biochemical parameters than single-factors.

  4. 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.

  5. Appetite regulating factors in pacu (Piaractus mesopotamicus): Tissue distribution and effects of food quantity and quality on gene expression.

    PubMed

    Volkoff, Hélène; Estevan Sabioni, Rafael; Coutinho, Luiz Lehmann; Cyrino, José Eurico Possebon

    2017-01-01

    The pacu Piaractus mesopotamicus is an omnivorous fish considered a promising species for aquaculture. Little is known about the endocrine regulation of feeding in this species. In this study, transcripts for orexin, cocaine and amphetamine regulated transcript (CART), cholecystokinin (CCK) and leptin were isolated in pacu. Orexin, CCK and leptin have widespread mRNA distributions in brain and periphery, CART is limited to the brain. To examine the role of these peptides in the regulation of feeding and energy status, mRNA expression levels were compared between fed and fasted fish and around feeding time. Both orexin and CART brain expressions were affected by fasting and displayed periprandial changes, suggesting a role in both short- and long-term regulation of feeding. CCK intestinal expression decreased in fasted fish and displayed periprandial changes, suggesting CCK acts as a peripheral satiety factor. Leptin was not affected by fasting but displayed periprandial changes, suggesting a role as a short-term regulator. To examine if these peptides are affected by diet, brain and gut expressions were assessed in fish fed with different diets containing soy protein concentrate. Food intake, weight gain and expressions of orexin, CART, CCK and leptin were little affected by replacement of fish protein with soy protein, suggesting that pacu is able to tolerate and grow well with a diet rich in plant material. Overall, our results suggest that orexin, CART, CCK and leptin are involved in the physiology of feeding of pacu and that their expressions are little affected by plant-based diets.

  6. 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

  7. 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

  8. Ventilatory flow relative to intrabuccal and intraopercular volumes in the serrasalmid fish Piaractus mesopotamicus during normoxia and exposed to graded hypoxia.

    PubMed

    Kalinin; Severi; Guerra; Costa; Rantin

    2000-05-01

    Ventilation volume Vg - mlH2O.min-1 ), respiratory frequency (fR - breaths.min-1) and tidal volume (VT - mlH2O.breath-1 ) were measured in a group of Piaractus mesopotamicus (650.4 +/- 204.7 g; n = 10) during normoxia and in response to graded hypoxia. The fR was maintained constant, around 100 breaths.min-1, from normoxia until the O2 tension of the inspired water (PiO2) of 53 mmHg, below which it increased progressively, reaching maximum values (157.6 +/- 6.3 breaths.min-1) at 10 mmHg. The VT rose from 1.8 +/- 0.1 to 6.0 +/- 0.5 and 5.7 +/- 0.4 mlH2O. breath-1 in the PiO2 of 16 and 10 mmHg, respectively. The Vg increased from 169.3 11.0 (normoxia) to 940.1 +/- 85.6 mlH2O. min-1 at the PiO2 of 16 mmHg, below which it also tended to decrease. A second group of fish (29 to 1510.0 g, n = 34) was used for the evaluation of allometric relationships concerning ventilation and dimensions of the buccal and opercular cavities. At maximum Vg, the VT corresponded to 93.2 +/- 2.4% of the buccal volume and 94.9 2.3% of the opercular volume, suggesting that the Vg of P. mesopotamicus is limited by the volumes of buccal and opercular cavities in severe hypoxia.

  9. Large-scale SNP discovery and construction of a high-density genetic map of Colossoma macropomum through genotyping-by-sequencing

    PubMed Central

    Nunes, José de Ribamar da Silva; Liu, Shikai; Pértille, Fábio; Perazza, Caio Augusto; Villela, Priscilla Marqui Schmidt; de Almeida-Val, Vera Maria Fonseca; Hilsdorf, Alexandre Wagner Silva; Liu, Zhanjiang; Coutinho, Luiz Lehmann

    2017-01-01

    Colossoma macropomum, or tambaqui, is the largest native Characiform species found in the Amazon and Orinoco river basins, yet few resources for genetic studies and the genetic improvement of tambaqui exist. In this study, we identified a large number of single-nucleotide polymorphisms (SNPs) for tambaqui and constructed a high-resolution genetic linkage map from a full-sib family of 124 individuals and their parents using the genotyping by sequencing method. In all, 68,584 SNPs were initially identified using minimum minor allele frequency (MAF) of 5%. Filtering parameters were used to select high-quality markers for linkage analysis. We selected 7,734 SNPs for linkage mapping, resulting in 27 linkage groups with a minimum logarithm of odds (LOD) of 8 and maximum recombination fraction of 0.35. The final genetic map contains 7,192 successfully mapped markers that span a total of 2,811 cM, with an average marker interval of 0.39 cM. Comparative genomic analysis between tambaqui and zebrafish revealed variable levels of genomic conservation across the 27 linkage groups which allowed for functional SNP annotations. The large-scale SNP discovery obtained here, allowed us to build a high-density linkage map in tambaqui, which will be useful to enhance genetic studies that can be applied in breeding programs. PMID:28387238

  10. Morphological and histochemical changes associated with massive infection by Neoechinorhynchus buttnerae (Acanthocephala: Neoechinorhynchidae) in the farmed freshwater fish Colossoma macropomum Cuvier, 1818 from the Amazon State, Brazil.

    PubMed

    de Matos, Lorena V; de Oliveira, Maria Inês B; Gomes, Ana Lúcia S; da Silva, Grazyelle S

    2017-03-01

    The study describes the morphological changes associated with parasitism by the intestinal acanthocephalan Neoechinorhynchus buttnerae in tambaqui juveniles Colossoma macropomum farmed in an excavated nursery, in Manaus (Amazon) in September 2013. After fish biometrics, analysis of macroscopic changes in morphology and counting of parasites, bowel fragments were fixed and submitted to histological and histochemical processing. All fish analyzed had acanthocephalans in the intestine; intestinal loops were milky white in color, with the presence of nodules with heavy parasitism. The changes in tissues that form the intestine varied according to the arrangement of the parasites: either free in the intestinal lumen or fixed by the proboscis on the organ wall. In the first case, the changes found were flaking, abrasion, compression, hypertrophy of goblet cells and disappearance of the villi on the mucosa, leukocytic cell infiltration in the submucosa, and muscle layer thickening. In the second case, in addition to these, other changes were observed as metaplasia in muscle tissue with its replacement by a loose connective tissue with severe leukocytic infiltration, edema in blood vessels, and necrotic foci. The histochemical analysis revealed that positive Alcian Blue mucosal cells (pH 2.5) were more expressive in parasitized intestines than in intestines not parasitized by N. buttnerae.

  11. Ras oncogene and Hypoxia-inducible factor-1 alpha (hif-1α) expression in the Amazon fish Colossoma macropomum (Cuvier, 1818) exposed to benzo[a]pyrene.

    PubMed Central

    da Silva, Grazyelle Sebrenski; Fé, Luciana Mara Lopes; da Silva, Maria de Nazaré Paula; Val, Vera Maria Fonseca de Almeida e

    2017-01-01

    Abstract Benzo[a]pyrene (B[a]P) is a petroleum derivative capable of inducing cancer in human and animals. In this work, under laboratory conditions, we analyzed the responses of Colossoma macropomum to B[a]P acute exposure through intraperitoneal injection of four different B[a]P concentrations (4, 8, 16 and 32 μmol/kg) or corn oil (control group). We analyzed expression of the ras oncogene and the Hypoxia-inducible factor-1 alpha (hif-1α) gene using quantitative real-time PCR. Additionally, liver histopathological changes and genotoxic effects were evaluated through the comet assay. Ras oncogene was overexpressed in fish exposed to 4, 8 of 16 μmol/kg B[a]P, showing 4.96, 7.10 and 6.78-fold increases, respectively. Overexpression also occurred in hif-1α in fish injected with 4 and 8 μmol/kg B[a]P, showing 8.82 and 4.64-fold increases, respectively. Histopathological damage in fish liver was classified as irreparable in fish exposed to 8, 16 and 32 μmol/kg μM B[a]P. The genotoxic damage increased in fish injected with 8 and 16 μmol/kg in comparison with the control group. Acute exposure of B[a]P was capable to interrupt the expression of ras oncogene and hif-1α, and increase DNA breaks due to tissue damage. PMID:28486571

  12. 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.

  13. 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.

  14. A simple method for the determination of fluoroquinolone residues in tilapia (Oreochromis niloticus) and pacu (Piaractus mesopotamicus) employing LC-MS/MS QToF.

    PubMed

    Quesada, Silvia Pilco; Paschoal, Jonas Augusto Rizzato; Reyes, Felix Guillermo

    2013-01-01

    The use of antimicrobials in livestock production is a powerful resource applied throughout the world to guarantee high yield and control bacterial diseases in aquaculture. However, residues of these substances in animal products represent a potential risk to consumer health when residue levels are above the established maximum residue limits (MRLs). Fluoroquinolones (FQs) are antimicrobials commonly used worldwide in aquaculture. The aim of this work was to develop and validate a simple analytical method for the simultaneous determination of norfloxacin, danofloxacin, enrofloxacin and ciprofloxacin levels in tilapia (Oreochromis niloticus) and pacu (Piaractus mesopotamicus) fillets using liquid chromatography-tandem mass spectrometry (LC-MS/MS) quadrupole time of flight (QToF). The FQs were extracted from the fillets with 1% acetic acid-methanol and 1% acetic acid-acetonitrile solutions using ultrasonic assistance. The clean-up was performed with hexane. Chromatographic separation was conducted in an XTerra RP18 column (2.1 × 150 mm, 5 µm) at 25 °C with a flow of 0.2 mL min⁻¹. The mobile phase consisted of 0.1% aqueous formic acid and acetonitrile, with gradient elution. The validation parameters for all FQs were linearity (>0.99), intra-day precision (CV of 1%-9%), inter-day precision (CV of 3%-17%), decision limit (63-126 ng g⁻¹), detection capability (76 -152 ng g⁻¹) and accuracy (90%-111%). The limit of quantification was lower than the MRL for each FQ, indicating that the method is suitable for the determination of the FQ levels in the fish fillets. The mass analyser of the QToF type was able to confirm the identities of the FQs with an error of the accuracy of the mass (reasons m/z) of less than 10 ppm.

  15. Food restriction increase the expression of mTORC1 complex genes in the skeletal muscle of juvenile pacu (Piaractus mesopotamicus).

    PubMed

    Paula, Tassiana Gutierrez de; Zanella, Bruna Tereza Thomazini; Fantinatti, Bruno Evaristo de Almeida; Moraes, Leonardo Nazário de; Duran, Bruno Oliveira da Silva; Oliveira, Caroline Bredariol de; Salomão, Rondinelle Artur Simões; Silva, Rafaela Nunes da; Padovani, Carlos Roberto; Santos, Vander Bruno Dos; Mareco, Edson Assunção; Carvalho, Robson Francisco; Dal-Pai-Silva, Maeli

    2017-01-01

    Skeletal muscle is capable of phenotypic adaptation to environmental factors, such as nutrient availability, by altering the balance between muscle catabolism and anabolism that in turn coordinates muscle growth. Small noncoding RNAs, known as microRNAs (miRNAs), repress the expression of target mRNAs, and many studies have demonstrated that miRNAs regulate the mRNAs of catabolic and anabolic genes. We evaluated muscle morphology, gene expression of components involved in catabolism, anabolism and energetic metabolism and miRNAs expression in both the fast and slow muscle of juvenile pacu (Piaractus mesopotamicus) during food restriction and refeeding. Our analysis revealed that short periods of food restriction followed by refeeding predominantly affected fast muscle, with changes in muscle fiber diameter and miRNAs expression. There was an increase in the mRNA levels of catabolic pathways components (FBXO25, ATG12, BCL2) and energetic metabolism-related genes (PGC1α and SDHA), together with a decrease in PPARβ/δ mRNA levels. Interestingly, an increase in mRNA levels of anabolic genes (PI3K and mTORC1 complex: mTOR, mLST8 and RAPTOR) was also observed during food restriction. After refeeding, muscle morphology showed similar patterns of the control group; the majority of genes were slightly up- or down-regulated in fast and slow muscle, respectively; the levels of all miRNAs increased in fast muscle and some of them decreased in slow muscle. Our findings demonstrated that a short period of food restriction in juvenile pacu had a considerable impact on fast muscle, increasing the expression of anabolic (PI3K and mTORC1 complex: mTOR, mLST8 and RAPTOR) and energetic metabolism genes. The miRNAs (miR-1, miR-206, miR-199 and miR-23a) were more expressed during refeeding and while their target genes (IGF-1, mTOR, PGC1α and MAFbx), presented a decreased expression. The alterations in mTORC1 complex observed during fasting may have influenced the rates of protein

  16. 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

  17. 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.

  18. 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.

  19. 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).

  20. 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

  1. Kinetic modeling to study the quality of tambaqui (Colossoma macropomum) sous vide during storage at different temperatures.

    PubMed

    Ramos, Fabiane C P; Ribeiro, Suezilde C A; Peixoto Joele, Maria R S; Sousa, Consuelo L; Lourenço, Lúcia F H

    2017-07-01

    This study aimed to assess the changes in quality of tambaqui sous vide during refrigerated storage using degradation kinetics. Tambaqui sous vide was prepared and stored at three temperatures (1, 4, 10 °C). The microorganism counts and the physicochemical analyses were analyzed every three days. The results obtained were fitted to the Labuza models and by Arrhenius equation. The results of the microbiological and physicochemical analyses obtained better fits to the zero-order model. The Arrhenius equation better fit to the velocity constants of the zero-order model, which showed that the changes in the values of attributes are related to temperature. Higher Ea values were found for the microorganism counts than for the physicochemical parameters, which proves the greater dependency of microorganisms on variations in temperature. The assessment of changes in quality based on temperature allows the storage conditions to be optimized.

  2. 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.

  3. Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia.

    PubMed

    Wood, Chris M; de Souza Netto, José Gadelha; Wilson, Jonathan M; Duarte, Rafael M; Val, Adalberto Luis

    2017-01-01

    The total rate of N-waste excretion (M N) in juvenile tambaqui living in ion-poor Amazonian water comprised 85 % ammonia-N (M Amm-N) and 15 % urea-N (M Urea-N). Both occurred mainly across the gills with only ~5 % of M Amm-N and ~39 % of M Urea-N via the urine. Tambaqui were not especially tolerant to high environmental ammonia (HEA), despite their great resistance to other environmental factors. Nevertheless, they were able to maintain a continued elevation of M Amm-N during and after 48-h exposure to 2.5 mmol L(-1) HEA. The normally negative transepithelial potential (-18 mV) increased to -9 mV during the HEA period, which would help to reduce branchial NH4(+) entry. During 3 h of acute environmental hypoxia (30 % saturation), M Amm-N declined, and recovered thereafter, similar to the response seen in other hypoxia-tolerant teleosts; M Urea-N did not change. However, during gradual hypoxia, M Amm-N remained constant, but M Urea-N eventually fell. The acute temperature sensitivities of M Amm-N and M N were low from 28 °C (acclimation) to 33 °C (Q10 ~1.5), but high (~3.8) from 33 to 38 °C, relative to [Formula: see text] (~1.9 throughout). In contrast, M Urea-N exhibited a different pattern over these temperature ranges (Q10 2.6 and 2.1, respectively). The nitrogen quotient (NQ = 0.16-0.23) was high at all temperatures, indicating a 60-85 % reliance on protein to fuel aerobic metabolism in these fasting animals. During steady-state aerobic exercise, [Formula: see text] and M Urea-N increased in parallel with velocity (up to 3.45 body lengths s(-1)), but M Amm (and thus M N) remained approximately constant. Therefore, the NQ fell progressively, indicating a decreasing reliance on protein-based fuels, as work load increased. In group feeding trials using 45 % protein commercial pellets, tambaqui excreted 82 % (range 39-170 %) of the dietary N within 24 h; N-retention efficiency was inversely related to the ration voluntarily consumed. M Amm-N peaked at 4-6 h, and M Urea-N at 6-9-h post-feeding, with an additional peak in M Amm-N only at 21 h. During subsequent fasting, M N stabilized at a high endogenous rate from 2 through 8 days post-feeding. Possible reasons for the high wasting of protein-N during both fasting and feeding are discussed.

  4. Long-term organic selenium supplementation overcomes the trade-off between immune and antioxidant systems in pacu (Piaractus mesopotamicus).

    PubMed

    Takahashi, Leonardo Susumu; Biller-Takahashi, Jaqueline Dalbello; Mansano, Cleber Fernando Menegasso; Urbinati, Elisabeth Criscuolo; Gimbo, Rodrigo Yukihiro; Saita, Marcos Vinícius

    2017-01-01

    Selenium (Se) is an essential nutrient for antioxidant defenses in fish because of its role in preventing immunosuppression caused by oxidative stress. In this study it was demonstrated the relation between the oxidative stress and immune status after a long Se supplementation period, as a result of the evaluation of immunological, hematological and antioxidant responses, as well as growth performance of pacu fed diets supplemented with different concentrations of organic selenium (0, 0.3, 0.6, 0.9, and 1.8 mg Se-yeast/kg, but the final analyzed selenium concentrations were 0.72, 0.94, 1.15, 1.57 and 2.51 mg/kg, respectively) for 65 days. Dietary Se supplementation at 1.15 mg Se-yeast/kg (analyzed value) restored the production of antioxidant enzymes (glutathione peroxidase (GPx) and glutathione S-transferase (GST)), and consequently allowed the increased of some immunological parameters (leukocyte respiratory burst activity and lysozyme activity), hematological parameters (red blood cell count (RBC), hematocrit (HTC), mean corpuscular volume (MCV), and white blood cell count (WBC)). Se supplementation in pacu diets at 1.15 mg Se-yeast/kg for 65 days improved immune response and antioxidant defenses, suggesting that oxidative stress impairs immune system response to prevent excessive reactive oxygen species in cells and indicating the occurrence of a physiological trade-off between immune and antioxidant systems. Higher Se levels, such as 1.57 mg Se-yeast/kg increased the leukocyte respiratory burst activity, the WBC and thrombocyte counts, the RBC and HTC, and the GST and GPx enzymes. However, 2.51 mg Se-yeast/kg decreased the lysozyme levels, the WBC and thrombocyte counts, the RBC, HTC and MCV, and the GST and GPx enzymes. Those findings are important to future studies because showed the negative effect of oxidative stress on immunity, and may help to prevent any inhibition of the expected immune response after immunomodulators administration and vaccination. Also it was possible to meet the dietary selenium requirement of pacu, that was estimated to be 1.56 mg/kg.

  5. [Praziquantel, levamisole and diflubenzuron in the control of Dolops carvalhoi (Crustacea: Branchiura) and Anacanthorus penilabiatus (Monogenea: Dactylogyridae) in Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae)].

    PubMed

    Schalch, Sergio Henrique Canello; de Moraes, Flávio Ruas; Soares, Vando Edésio

    2009-01-01

    This assay evaluated the control efficacy of diflubenzuron, praziquantel and levamisole added to the diet of pacu (Piaractus mesoptamicus) infected with Anacanthorus penilabiatus and Dolops carvalhoi. 19 water tanks of 300 L capacity were utilized with 28 fish in each one. The treatments were made by mixing the active principles in the diet. The experiment was evaluated in four harvests done 1 day before and 3, 7 and 15 days after the treatment. The medicated feeding was applied for 7 days. The results of efficacy suggest that the diflubenzuron alone or associated with levamisole and praziquantel was efficient against the crustacean D. carvalhoi and the efficacy in the 3, 7 and 15 days evaluations ranged from 96.2 to 100%. Against the monogenean the drugs did not present efficacy. The results suggest the use of diflubenzuron for the control of D. carvalhoi in captive fishes in special conditions.

  6. 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.

  7. 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.

  8. One-step purification of metallothionein extracted from two different sources.

    PubMed

    Honda, Rubens T; Araújo, Roziete Mendes; Horta, Bruno Brasil; Val, Adalberto L; Demasi, Marilene

    2005-06-25

    We describe a one-step purification of hepatic metallothionein from the Amazon fish Colossoma macropomum injected with cadmium and from the copper-loaded metallothionein from the yeast Saccharomyces cerevisiae, performed by affinity chromatography through metal-chelating columns. Yeast metallothionein was purified from Cu2+-loaded resin and eluted by a continuous EDTA gradient whereas hepatic metallothionein extracted from fishes was purified by Ni2+-loaded resin and eluted by a continuous imidazol gradient. Purified metallothioneins were evaluated by SDS-PAGE and characterized by UV spectra of the apo- and Cd2+-loaded protein. This method allowed high purity and yield as well as rapid one-step extraction of both metal-loaded and apoprotein.

  9. Rainforest metropolis casts 1,000-km defaunation shadow.

    PubMed

    Tregidgo, Daniel J; Barlow, Jos; Pompeu, Paulo S; de Almeida Rocha, Mayana; Parry, Luke

    2017-08-08

    Tropical rainforest regions are urbanizing rapidly, yet the role of emerging metropolises in driving wildlife overharvesting in forests and inland waters is unknown. We present evidence of a large defaunation shadow around a rainforest metropolis. Using interviews with 392 rural fishers, we show that fishing has severely depleted a large-bodied keystone fish species, tambaqui (Colossoma macropomum), with an impact extending over 1,000 km from the rainforest city of Manaus (population 2.1 million). There was strong evidence of defaunation within this area, including a 50% reduction in body size and catch rate (catch per unit effort). Our findings link these declines to city-based boats that provide rural fishers with reliable access to fish buyers and ice and likely impact rural fisher livelihoods and flooded forest biodiversity. This empirical evidence that urban markets can defaunate deep into rainforest wilderness has implications for other urbanizing socioecological systems.

  10. Spectrofluorimetric study of the interaction of methyl-parathion with fish serum albumin.

    PubMed

    Silva, Dilson; Cortez-Moreira, Madelayne; Bastos, Vera Lúcia Freire Cunha; Bastos, Jayme Cunha; Cortez, Célia Martins

    2010-09-01

    The interaction of methyl-parathion with the albumin of Piaractus mesopotamicus (Holmberg 1887) (= pacu), a fish species typical of Brazilian rivers, was studied and the results compared with known values for human and bovine albumin obtained in an earlier investigation. Methyl-parathion (O,O-dimethyl O-p-nitrophenyl phosphorothioate) is an organophosphorous pesticide still used in agriculture and fish farming in many countries. The fluorescence quenching technique with tryptophan as a natural probe was used to detect for the presence of methyl-parathion. Fluorescence can be mathematically expressed by the Stern-Volmer equation to calculate quenching constants, and changes in the behavior of Stern-Volmer curves at different temperatures indicate the nature of the mechanism causing the quenching. Our results indicate that methyl-parathion forms a complex with fish albumin. The estimated association constant is 9.73 x 103 (+/- 4.9 x 102) M(-1) at 25 degrees C.

  11. Effects of Glyphosate-Based Herbicide Sub-Lethal Concentrations on Fish Feeding Behavior.

    PubMed

    Giaquinto, Percilia Cardoso; de Sá, Marina Borges; Sugihara, Vanessa Seiko; Gonçalves, Bruno Bastos; Delício, Helton Carlos; Barki, Assaf

    2017-04-01

    Glyphosate-based herbicides are widely used in agricultural systems. Although the target organism are particularly plant organisms, there are numerous studies showing adverse effects in aquatic animals, such as inhibition of acetyl cholinesterase, effects on kidney, liver, and gill and stressors effects. This study analyzed the effects of commercial formulation of glyphosate on feeding behavior in Pacu (Piaractus mesopotamicus). Fish were exposed to three glyphosate concentrations (0.2, 0.6, and 1.8 ppm) for 15 days. At concentrations of 0.2 and 0.6 ppm, food intake decreased on day 13 and then returned to normal on day 15. At the highest glyphosate-based herbicide concentration, 1.8 ppm, food consumption decreased dramatically and did not recover on day 15. This study showed that glyphosate-based herbicide at sub-lethal concentrations can affect feed intake in pacu and consequently inhibits its growth.

  12. Condition factor variations over time and trophic position among four species of Characidae from Amazonian floodplain lakes: effects of an anomalous drought.

    PubMed

    Tribuzy-Neto, I A; Conceição, K G; Siqueira-Souza, F K; Hurd, L E; Freitas, C E C

    2017-08-17

    The effects of extreme droughts on freshwater fish remain unknown worldwide. In this paper, we estimated the condition factor, a measure of relative fitness based on the relationship of body weight to length, in four fish species representing two trophic levels (omnivores and piscivores) from Amazonian floodplain lakes for three consecutive years: 2004, 2005 (an anomalous drought year), and 2006. The two omnivores, Colossoma macropomum and Mylossoma duriventre, exhibited trends consistent with their life cycles in 2004 and 2006: high values during the hydrologic seasons of high water, receding water, and low water, with a drop following reproduction following the onset of rising water. However during the drought year of 2005 the condition factor was much lower than normal during receding and low water seasons, probably as a result of an abnormal reduction in resource availability in a reduced habitat. The two piscivorous piranhas, Serrasalmus spilopleura and S. elongatus, maintained relatively stable values of condition factor over the hydrologic cycles of all three years, with no apparent effect of the drought, probably because the reduction in habitat is counterbalanced by the resulting increase in relative prey density. We suggest that if predictions of increasing drought in the Amazon are correct, predatory species may benefit, at least in the short run, while omnivores may be negatively affected.

  13. 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.

  14. 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

  15. [Characterization of the genetic diversity of the fish Brycon henni (Characiformes: Characidae) in central Colombia with RAPD markers].

    PubMed

    Pineda Santis, Hermes; Arboleda Chacón, Lucy; Echeverry Echavarria, Amparo; Urcuqui Inchima, Silvio; Pareja Molina, Diego; Olivera Angel, Martha; Builes Gómez, Juan

    2007-01-01

    Knowledge on the genetic diversity of wild fish species is essential for conservation and appropriate management of individuals in repopulation programs. In Colombia, Brycon henni has been reported in the Magdalena and Cauca river basins, but the population and range have diminished as a consequence of anthropic activities. In this study, the Random Amplified Polymorphic DNA (RAPD) was used to estimate the actual genetic structure in this species. For the purpose, six sample sites located in the department of Antioquia (Central Chain Mountains of Colombia) were used. Thirty five primers (87.5%), out of forty used, yielded 1 466 reliable and consistent fragments; 417 were considered as unique fragments able to discriminate among the Magdalena (Humarada-1 and Humarada-2) and Cauca (Piedras, La Clara y Guaracfi) river basins samples, suggesting that each is a discrete unit. This diversity suggests that anthropic effects of over fishing, dam building, deforestation and water pollution, have contributed to the isolation of these fish groups on the high mountains. Brycon moorei and Colossoma macropomum, as an interspecific control groups, were placed out of the B. henni general group, confirming their taxonomic classification through morphologic data. The RAPD technique was useful to know the genetic diversity and to discriminate among B. henni populations from different geographic origins, as a basis for an appropriate plan of repopulation, conservation and wildlife management.

  16. Characterization, specificity and sensibility of produced anti-Rhamdia quelen vitellogenin in Brazilian fish species.

    PubMed

    Moura Costa, Daniele Dietrich; Bozza, Dandie Antunes; Rizzo, Luiz Eduardo; Garcia, Juan; Costa, Michele Dietrich Moura; de Oliveira Ribeiro, Ciro Alberto

    2016-12-01

    Endocrine-disrupting chemicals (EDCs) are widespread used and can interfere on hormone regulation with adverse consequences for both biota and human. Vitellogenin (vtg) is a yolk precursor protein synthesized by the liver in response to estrogen. In order to characterize the vtg of tropical fish Rhamdia quelen and establish a molecular biomarker, adult male individuals were exposed to 17-β-estradiol (E2) for vtg induction and anti-R. quelen vtg polyclonal antibodies production. Vitellogenic female fish were used as positive control group. E2-induced vtg was characterized as a glycolipophosphoprotein of high molecular mass with peptide mass fingerprint very similar in E2-exposed male and vitellogenic female fish. A polyclonal serum containing anti-R. quelen vtg antibodies was produced and showed high specificity and sensibility to detect the vtg of three fish species: R. quelen, Piaractus mesopotamicus and Prochilodus lineatus. Wildlife and laboratory studies reported that EDCs released into the environment may alter the levels of plasma vtg in male fish, making this protein a valuable biomarker of xenoestrogens exposure. Then, we propose the use of anti-R. quelen vtg as a tool for biomonitoring studies and water quality assessment in Brazil and South American countries where the three fish species occur.

  17. 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.

  18. Melatonin affects conjugation of 4-hydroxynonenal with glutathione in liver of pacu, a hypoxia-tolerant fish.

    PubMed

    Bastos, F F; Tobar, S A L; Dantas, R F; Silva, E S; Nogueira, N P A; Paes, M C; Righi, B D P; Bastos, J Cunha; Bastos, V L F Cunha

    2013-10-01

    In cytosol from liver of pacu, Piaractus mesopotamicus, a hypoxia-tolerant fish that dwells in Pantanal, we found an enzyme activity capable of modulating the alkenal 4-hydroxy-2-nonenal (HNE) by conjugating it with glutathione (GST-HNE activity). HNE is a downstream metabolite from the oxidation of polyunsaturated fatty acids by reactive oxygen species arisen from mitochondria of animal cells. HNE production may increase more intensively under oxidative stress. Harmful effects to cell survival may occur when HNE increases over 10(-4) M. Pacus submitted to hypoxia in July (cold season in Pantanal) showed 40% less of this GST-HNE conjugating activity in their liver cytosol. Injecting pacus subjected to hypoxia during the cold season with a summer physiological dose of melatonin caused their liver cytosolic GST-HNE activity to increase up to the levels found in the warm season. From October to March (warm season in Pantanal), pacus are prone to oxidative stress particularly during potamodromous active oxygen-demanding swimming, when they migrate up rivers to spawn. Thus, our findings point out that the higher levels of melatonin in circulation during the summer are important to avoid the increase of 4-HNE inside liver cells of this fish species.

  19. 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

  20. 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.

  1. 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

  2. A Morphological and Molecular Study of Spectatus spectatus (Kathlaniidae), Including Redescription of the Species and Amendment of Genus Diagnosis.

    PubMed

    Pereira, Felipe B; Tavares, Luiz E R; Paiva, Fernando; Scholz, Tomáš; Luque, José L

    2015-08-01

    Spectatus spectatus Travassos, 1923 (Nematoda: Kathlaniidae) found in the intestine of Piaractus mesopotamicus (Holmberg, 1887) (Characiformes: Serrasalmidae) from the River Miranda, Mato Grosso do Sul, Brazil is redescribed based on morphological evaluation of newly collected material and examination of type and voucher specimens from the Coleção Helmintológica do Instituto Oswaldo Cruz. The following characteristics previously unreported or insufficiently described were observed: morphology of lips, presence of lamellae-like supplementary lips, presence of pharynx and cuticular ring surrounding the oral opening associated with a complex cuticular apparatus anterior to the pharynx, the number and arrangement of caudal papillae (13 pairs plus 1 unpaired), and the position of nerve ring. Since S. spectatus is the type species of Spectatus, the diagnosis of this Neotropical genus is amended. Synonymy of Chabaudinema Díaz-Ungría, 1968 with Spectatus, first proposed in 1980 by Baker, is supported by the present data. Molecular data that include the first sequence of the SSU rDNA for any species of Spectatus indicate a basal position of S. spectatus within Cosmocercoidea, forming a distant lineage from that comprising 2 species of Falcaustra Lane, 1915. This separate position of S. spectatus supports validity of the genus.

  3. 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.

  4. 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.

  5. Systematic variation in the pattern of gene paralog retention between the teleost superorders Ostariophysi and Acanthopterygii.

    PubMed

    Garcia de la Serrana, Daniel; Mareco, Edson A; Johnston, Ian A

    2014-04-01

    Teleost fish underwent whole-genome duplication around 450 Ma followed by diploidization and loss of 80-85% of the duplicated genes. To identify a deep signature of this teleost-specific whole-genome duplication (TSGD), we searched for duplicated genes that were systematically and uniquely retained in one or other of the superorders Ostariophysi and Acanthopterygii. TSGD paralogs comprised 17-21% of total gene content. Some 2.6% (510) of TSGD paralogs were present as pairs in the Ostariophysi genomes of Danio rerio (Cypriniformes) and Astyanax mexicanus (Characiformes) but not in species from four orders of Acanthopterygii (Gasterosteiformes, Gasterosteus aculeatus; Tetraodontiformes, Tetraodon nigroviridis; Perciformes, Oreochromis niloticus; and Beloniformes, Oryzias latipes) where a single copy was identified. Similarly, 1.3% (418) of total gene number represented cases where TSGD paralogs pairs were systematically retained in the Acanthopterygian but conserved as a single copy in Ostariophysi genomes. We confirmed the generality of these results by phylogenetic and synteny analysis of 40 randomly selected linage-specific paralogs (LSPs) from each superorder and completed with the transcriptomes of three additional Ostariophysi species (Ictalurus punctatus [Siluriformes], Sinocyclocheilus species [Cypriniformes], and Piaractus mesopotamicus [Characiformes]). No chromosome bias was detected in TSGD paralog retention. Gene ontology (GO) analysis revealed significant enrichment of GO terms relative to the human GO SLIM database for "growth," "Cell differentiation," and "Embryo development" in Ostariophysi and for "Transport," "Signal Transduction," and "Vesicle mediated transport" in Acanthopterygii. The observed patterns of paralog retention are consistent with different diploidization outcomes having contributed to the evolution/diversification of each superorder.

  6. Feeding strategy with alternate fasting and refeeding: effects on farmed pacu production.

    PubMed

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

    2011-04-01

    A 36-day trial was conducted to determine the effects of repetitive periods of food restriction and refeeding on growth and energy metabolism in pacu (Piaractus mesopotamicus). A total 264 juvenile fish (36.9±2.8 g) were fed with the experimental diet for 36 days using three regimes: (i) feeding daily to satiation (FD); (ii) no feed for 3 days, then feeding the same amount offered to the control groups for the next 3 days (NF/R controlled); and (iii) no feed for 3 days, then feeding to apparent satiation for the next 3 days (NF/R at satiation). The treatments were distributed into four tanks each. WG and SGR were higher in FD group. Fish refed showed hyperphagia just up to the second day of refeeding. The worst feed conversion rate and the lowest protein efficiency ratio were found in fish NF/R controlled. The lowest values of visceral fat somatic index were found in both fasted fish groups, particularly in NF/R at satiation. The LL and glycogen concentrations, and the hepatosomatic index were all elevated in both feed restricted fish. Muscle lipid showed a tendency to decrease after the cycle of fasting and refeeding. Plasma free fatty acids and glucose levels were elevated in fish subjected to feeding restrictions while serum triglycerides levels were reduced. Triiodothyronine levels were significantly depressed in fish from the NF/R-controlled group and remained at the same levels as the control fish in fish NF/R at satiation. Results indicated that fish subjected to cyclic periods of 3-day satiation or controlled feeding after 3-days of fasting were unable to achieve the final body weight of fish fed to satiation after 36 days. © 2010 Blackwell Verlag GmbH.

  7. Systematic Variation in the Pattern of Gene Paralog Retention between the Teleost Superorders Ostariophysi and Acanthopterygii

    PubMed Central

    Garcia de la serrana, Daniel; Mareco, Edson A.; Johnston, Ian A.

    2014-01-01

    Teleost fish underwent whole-genome duplication around 450 Ma followed by diploidization and loss of 80–85% of the duplicated genes. To identify a deep signature of this teleost-specific whole-genome duplication (TSGD), we searched for duplicated genes that were systematically and uniquely retained in one or other of the superorders Ostariophysi and Acanthopterygii. TSGD paralogs comprised 17–21% of total gene content. Some 2.6% (510) of TSGD paralogs were present as pairs in the Ostariophysi genomes of Danio rerio (Cypriniformes) and Astyanax mexicanus (Characiformes) but not in species from four orders of Acanthopterygii (Gasterosteiformes, Gasterosteus aculeatus; Tetraodontiformes, Tetraodon nigroviridis; Perciformes, Oreochromis niloticus; and Beloniformes, Oryzias latipes) where a single copy was identified. Similarly, 1.3% (418) of total gene number represented cases where TSGD paralogs pairs were systematically retained in the Acanthopterygian but conserved as a single copy in Ostariophysi genomes. We confirmed the generality of these results by phylogenetic and synteny analysis of 40 randomly selected linage-specific paralogs (LSPs) from each superorder and completed with the transcriptomes of three additional Ostariophysi species (Ictalurus punctatus [Siluriformes], Sinocyclocheilus species [Cypriniformes], and Piaractus mesopotamicus [Characiformes]). No chromosome bias was detected in TSGD paralog retention. Gene ontology (GO) analysis revealed significant enrichment of GO terms relative to the human GO SLIM database for “growth,” “Cell differentiation,” and “Embryo development” in Ostariophysi and for “Transport,” “Signal Transduction,” and “Vesicle mediated transport” in Acanthopterygii. The observed patterns of paralog retention are consistent with different diploidization outcomes having contributed to the evolution/diversification of each superorder. PMID:24732281

  8. 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.

  9. 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

  10. A comparison of adrenergic stress responses in three tropical teleosts exposed to acute hypoxia.

    PubMed

    Perry, S F; Reid, S G; Gilmour, K M; Boijink, C L; Lopes, J M; Milsom, W K; Rantin, F T

    2004-07-01

    Experiments were performed to assess the afferent and efferent limbs of the hypoxia-mediated humoral adrenergic stress response in selected hypoxia-tolerant tropical fishes that routinely experience environmental O(2) depletion. Plasma catecholamine (Cat) levels and blood respiratory status were measured during acute aquatic hypoxia [water Po(2) (Pw(O(2))) = 10-60 mmHg] in three teleost species, the obligate water breathers Hoplias malabaricus (traira) and Piaractus mesopotamicus (pacu) and the facultative air breather Hoplerythrinus unitaeniatus (jeju). Traira displayed a significant increase in plasma Cat levels (from 1.3 +/- 0.4 to 23.3 +/- 15.1 nmol/l) at Pw(O(2)) levels below 20 mmHg, whereas circulating Cat levels were unaltered in pacu at all levels of hypoxia. In jeju denied access to air, plasma Cat levels were increased markedly to a maximum mean value of 53.6 +/- 19.1 nmol/l as Pw(O(2)) was lowered below 40 mmHg. In traira and jeju, Cat release into the circulation occurred at abrupt thresholds corresponding to arterial Po(2) (Pa(O(2))) values of approximately 8.5-12.5 mmHg. A comparison of in vivo blood O(2) equilibration curves revealed low and similar P(50) values (i.e., Pa(O(2)) at 50% Hb-O(2) saturation) among the three species (7.7-11.3 mmHg). Thus Cat release in traira and jeju occurred as blood O(2) concentration was reduced to approximately 50-60% of the normoxic value. Intravascular injections of nicotine (600 nmol/kg) elicited pronounced increases in plasma Cat levels in traira and jeju but not in pacu. Thus the lack of Cat release during hypoxia in pacu may reflect an inoperative or absent humoral adrenergic stress response in this species. When allowed access to air, jeju did not release Cats into the circulation at any level of aquatic hypoxia. The likeliest explanation for the absence of Cat release in these fish was that air breathing, initiated by aquatic hypoxia, prevented Pa(O(2)) values from falling to the critical threshold required