The aim of this study was to evaluate the effect of dietary supplementation with the autochthonous probiotic bacteria Bacillus cereus on growth performance, haematological parameters and survival of tambaqui (Colossoma macropomum). Tambaqui fingerlings (0.94 ± 0.02 g) were fed for 120 days the following diets: basal (without probiotic) and three supplemented diets (4.2 × 10 4 , 3.9 × 10 6 and 3.3 × 10 8 CFU/ g). Growth performance and haematological parameters were evaluated every 30 days. Thereafter, fish were challenged against Aeromonas hydrophila and survival was evaluated. Probiotic B. cereus improved weight and length gains (p < 0.05), and increased neutrophils and thrombocyte counts (p < 0.05) in tambaqui supplemented with 3.9 × 10 6 CFU/g diet. Challenged fish fed unsupplemented diet presented the lowest survival rate (33.4%) while fish fed diets supplemented at 4.2 × 10 4 , 3.9 × 10 6 and 3.3 × 10 8 CFU/g B. cereus had 88.8%, 80.5% and 80.5% relative per cent survival respectively. These results demonstrated that B. cereus supplemented as probiotics to C. macropomum for 120 days improved physiological and haematological responses, leading to enhanced survival in this fish species. K E Y W O R D Samazon, bacterium, fish, haematology, nutrition, performance

The banded cichlid (Herus severus) is an Amazonian species with potential as ornamental fish, however basic handlings as quantity and feeding frequency as well as stocking density in larviculture are still unknown in order to allow the rational production of this species in captivity. Then the objective was to evaluate the amount of food, feeding frequency and stocking density during the larviculture of Herus severus. Therefore, two experiments were conducted: the first assessed the food concentration (100, 150, 200, 250 and 300 Artemia larvae-1) and feed rate (2 or 4 meals day-1), and the second experiment evaluated different stocking densities (1, 5, 10, 15, 20 larvae L-1) with four replications each. Feeding of 250 nauplii larva day-1 distributed in four daily meals promoted the highest weight, length, specific growth rate, weight gain and survival. In the second experiment, reduction in growth was observed with increased in density due to lower concentrations of dissolved oxygen and elevated total ammonia from 5 larvae L-1. Thus, to promote the rational cultivation of the Banded cichlid larvae in captivity, the species should be reared at 5 larvae L-1 fed with 250nauplii distributed along 4 daily meals.

RESUMOO tambaqui Colossoma macropomum é criado em diferentes sistemas e ambientes com boa produção em tanques-rede. O objetivo deste trabalho foi avaliar o crescimento do tambaqui em diferentes densidades de estocagem em tanques-rede em lago abastecido com água de chuva e seus efeitos sobre a qualidade ambiental. O experimento foi conduzido em fases consecutivas: recria nas densidades de 50, 100, 200 e 300 alevinos m -3 e terminação nas densidades de 20, 40, e 60 juvenis m -3. A temperatura da água, oxigênio dissolvido, pH e condutividade da água foram medidas diariamente. Amostras de sedimento e água foram coletadas para análise de nitrogênio e fósforo mensalmente. Na recria, a produção de 14,03 kg m -3 foi significativamente maior na densidade de 300 alevinos m . A sobrevivência na recria foi superior a 97%. Na terminação, o ganho de peso e o crescimento específico foram inversamente proporcionais as densidades. A conversão alimentar e o fator de condição não foram influenciados pelas densidades testadas. A densidade de 20 juvenis m -3 é a mais adequada para a terminação de tambaquis em tanques-rede. A criação de tambaqui em tanques-rede não alterou os níveis de nitrogênio e fósforo da água do lago. Aumento dos teores de matéria orgânica, nitrogênio e fósforo foram verificados no sedimento abaixo dos tanques-rede, sem causar eventos de eutrofização. O presente estudo demonstrou que a criação de tambaquis em tanques-rede é viável em lagos abastecidos com água de chuva e pode integrar-se aos preceitos dos usos múltiplos da água. PALAVRAS-CHAVE: produção, Colossoma macropomum, nitrogênio, fósforo, qualidade ambiental Tambaqui growth in response to stocking density in cages ABSTRACTThe tambaqui Colossoma macropomum is rearing on different systems and environments and has shown good production in cages. The aim of this study was to evaluate the growth of tambaqui at different stocking densities in a lake supplied by rainwater and its effects on environmental quality. The experiment was conducted in consecutive phases: nursery at densities of 50, 100, 200 and 300 fingerlings m -3 and growth at densities of 20, 40 and 60 juveniles m -3. Water temperature, dissolved oxygen, pH and conductivity were monitored daily. Sediment and water samples were collected for analyses of nitrogen and phosphorus monthly. In the nursery, yield of 14,03 kg m -3 was significantly higher for fish at 300 fingerlings m -3. The highest weight gain was obtained at 50 fingerlings m -3 . Survival over 97% was observed in the nursery. In the growth phase, weight gain and specific growth were inversely proportional to densities. Feed conversion and condition factor were not influenced by the evaluated densities. The density of 20 juveniles m -3 is more adequate to grow tambaqui in cages. Tambaqui cage culture did not alter the levels of nitrogen and phosphorus nutrients of lake water. Increased levels of organic matter, nitrogen and phosphorus in the sediment below the cages were verified without creating events of eutrophication. The results sho...

The study evaluated productive performance of larvae Nannostomus beckfordi submitted to feeding management (Experiment one) and different stock density (Experiment two) in captivity conditions. The first experiment evaluated feeding rate (100 and 200 nauplii of artemia larvae −1 day −1 ) and feeding frequency (2 and 4× per day). Second experiment evaluated different stock density (1, 5, 10, 20, 40 larvae per litre). At the end of 15 days, for both experiment, the survival and productive performance such as total length (TL), final weight (FW), specific development rate (SDR), specific growth rate (SGR), uniformity for weight (UW) uniformity for length (UL) and relative condition factor (Kr) was determined. For the main results, there is no significant difference to the rate and feeding frequency. The stock density has no significant difference for UW, Kr and survival. Nonetheless, a reduction in the TL, FW, SDR, SGR and FW with the increase in density (20 for 40 larvae per litre) was observed. Thus, for this species Nannostomus beckfordi during to initial stage using exogenous feeding, it is recommended 20 larvae per litre fed with 100 nauplii per larvae having two meals per day.

The objective of this work was to evaluate the acute toxicity of formalin and histopathological effects on the Amazon ornamental fish, bluespotted coridora (Corydoras melanistius). A randomized design was used, with ten concentrations of formalin (40%) (0, 3, 6, 12, 25, 50, 100, 150, 200 and 250mg.L -1 ) with four replicates and five fish per container (3L) in static system for 96 hours. The moribund fish were killed and fixed in 10% formalin to proceed the histopathological analysis of gill, liver and kidney. At the end of this experiment the following mortality rates (%) were obtained in increasing order of exposure: 0, 0, 0, 0, 0, 65, 85, 100, 100 and 100%. The lethal concentration 50% (LC 50-96h (I) ) estimated was 50.76 mg.L -1 with regression of y = 0.51x, and r2 = 0.80. Further, in higher concentrations morphological changes as gill hyperplasia, with filling of interlamellar spaces, disorganization of liver arrangement, and necrosis in kidney were observed. In this study, the formalin can be considered slightly toxic to bluespotted corydora, and cause morphological changes when exposed to high concentrations. The use of formalin to treat of ornamental fish in the inner river of capture with wrong concentration can provoke negative environmental and biological effects.

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The familial placement of four genera, Mycodidymella, Petrakia, Pseudodidymella, and Xenostigmina, was taxonomically revised based on morphological observations and phylogenetic analyses of nuclear rDNA SSU, LSU, tef1, and rpb2 sequences. ITS sequences were also provided as barcode markers. A total of 130 sequences were newly obtained from 28 isolates which are phylogenetically related to Melanommataceae (Pleosporales, Dothideomycetes) and its relatives. Phylogenetic analyses and morphological observation of sexual and asexual morphs led to the conclusion that Melanommataceae should be restricted to its type genus Melanomma, which is characterised by ascomata composed of a well-developed, carbonaceous peridium, and an aposphaeria-like coelomycetous asexual morph. Although Mycodidymella, Petrakia, Pseudodidymella, and Xenostigmina are phylogenetically related to Melanommataceae, these genera are characterised by epiphyllous, lenticular ascomata with well-developed basal stroma in their sexual morphs, and mycopappus-like propagules in their asexual morphs, which are clearly different from those of Melanomma. Pseudodidymellaceae is proposed to accommodate these four genera. Although Mycodidymella and Xenostigmina have been considered synonyms of Petrakia based on sexual morphology, we show that they are distinct genera. Based on morphological observations, these genera in Pseudodidymellaceae are easily distinguished by their synasexual morphs: sigmoid, multi-septate, thin-walled, hyaline conidia (Mycodidymella); globose to ovoid, dictyosporus, thick-walled, brown conidia with cellular appendages (Petrakia); and clavate with a short rostrum, dictyosporus, thick-walled, brown conidia (Xenostigmina). A synasexual morph of Pseudodidymella was not observed. Although Alpinaria was treated as member of Melanommataceae in a previous study, it has hyaline cells at the base of ascomata and pseudopycnidial, confluent conidiomata which is atypical features in Melanommataceae, and is treated as incertae sedis.

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