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 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.
A total of 281 specimens of freshwater armored ornamental fish species (Leporacanthicus galaxias, Lasiancistrus saetiger, Cochliodon sp., Hypostomus sp., Pseudacanthicus spinosus, Ancistrus sp. and Rineloricaria cf. lanceolata) were captured at the hydrological basin of Guamá River, Pará, Brazil. The infection by Trypanosoma spp. was inspected. The morphological and morphometric characterization of the parasites and the hematological parameters were determined. Leporacanthicus galaxias and Pseudacanthicus spinosus presented 100% infection prevalence, and the other species showed a variable prevalence of infection. The parasites showed clearly different morphotypes and dimensions, and probably belong to different species. The hematological response to the infection varied with the host. Cochliodon sp. showed no differences between infected and not infected fish. In other species several modifications on some hematological parameters were found, but apparently without causing disease. It is emphasized the possibility of introduction of the parasites in new environments due to the artificial movements of these ornamental fish.
Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 106 CFU/g and 1 × 108 CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 108 CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 108 CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 108 CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load.
RESUMO Este trabalho teve como objetivo avaliar a fauna parasitária de tambaquis na região do Baixo São Francisco-AL/SE-Brasil e correlacionar os índices de prevalência e intensidade média com fatores bióticos e abióticos. Foram coletados 252 espécimes para análise parasitológica de 10 pisciculturas. Os parasitos foram contabilizados, identificados, e determinaram-se os índices de prevalência e intensidade média, que foram correlacionados com fatores bióticos e abióticos. Dos peixes coletados, 65,5% estavam parasitados por pelo menos um táxon. Foram encontrados 10 táxons: Monogeneas, Ichthyophthirius multifiliis, tricodinídeos, Piscinoodinium pillulare, Ichthyobodo sp., Dolops carvalhoi, Lernaea cyprinacea, Procamallanus (Spirocamallanus) inopinatus, Henneguya sp. e Myxobolus sp. As maiores prevalências foram encontradas para Monogeneas (49,2%) e Myxobolus sp. (31,5%). Correlações negativas entre prevalência e fatores bióticos (peso e comprimento) foram observadas para Monogeneas (r2= -0,49; r2= -0,43), Myxobolus sp. (r²= -0,46; r²= -0,39) e Henneguya sp. (r²= -0,41; r²= -0,39). O fator abiótico temperatura apresentou correlação negativa com as prevalências de Lernaea cyprinacea (r= -0,39) e tricodinídeos (r= -0,33), enquanto a condutividade elétrica apresentou correlação positiva (r= 0,40) com a prevalência de tricodinídeos. Conclui-se que a fauna parasitária dos tambaquis cultivados na região do Baixo São Francisco é diversificada e com a carga parasitária dependente da qualidade de água e do estágio de desenvolvimento dos peixes.
RESUMO: A fitoterapia vem sendo utilizada em criação de peixes a fim de promover estabilidade no ambiente de cultivo e na profilaxia de doenças, contribuindo para melhoria do bem-estar animal. Dentre os fitoterápicos, a canela (Cinnamon zeylanicum) possui atividade antioxidante, antiinflamatória, antifúngica e antiparasitária, além de efeito imunoestimulante. O objetivo do trabalho foi avaliar os efeitos do extrato aquoso de canela sobre o desempenho produtivo de larvas do peixe ornamental amazônico Pyrrhulina brevis. Foram avaliadas cinco concentrações de extrato aquoso (0; 0,25; 0,50; 0,75 e 1,0 g/L) em 4 repetições, durante 20 dias. A utilização de 1,0g/L de extrato de Cinnamon zeylanicum favorece o desempenho produtivo das larvas, com melhores resultados para comprimento total final, taxa de crescimento específico para comprimento e promove 100% de sobrevivência ao lote (P<0,05). Este é o primeiro relato da eficácia do uso de extrato aquoso de canela como promotor de crescimento na larvicultura de peixes.Palavras-chave: fitoterapia, peixe ornamental, sanidade.
AQUEOUS CINNAMON EXTRACT AS A GROWTH PROMOTER FOR LARVAE OF THE ORNAMENTAL AMAZON FISH Pyrrhulina brevisABSTRACT: Phytotherapy has been used in fish farming to promote stability in the rearing environment and for the prophylaxis of diseases, improving animal well-being. Among phytotherapeutic agents, cinnamon (Cinnamon zeylanicum) exhibits antioxidant, anti-inflammatory, antifungal and antiparasitic activity, in addition to immunostimulatory effects. The objective of this study was to evaluate the effect of an aqueous cinnamon extract on the productive performance of larvae of the ornamental Amazon fish Pyrrhulina brevis. Five concentrations of the aqueous extract (0, 0.25, 0.5, 0.75 and 1.0 g/L) were evaluated in four replicates over a period of 20 days. The use of 1.0 g/L of Cinnamon zeylanicum extract favored larval performance, improving final total length and the specific growth rate in length and promoting 100% survival of the batch (P<0.05). This is the first study demonstrating the efficacy of the use of aqueous cinnamon extract as a growth promoter in fish larviculture.
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