Environmental and ichthyofaunistic characteristics of Amazonian streams with and without fish farm.

The environmental impacts caused by fish farming can lead to changes in aquatic ecosystems, especially in fish communities. In this study, we investigated possible changes in water quality, in the number of species and individuals of the same species caused by the construction of fish nurseries in dammed Amazonian streams. For this purpose, four streams located in the municipalities of Novo Airão and Presidente Figueiredo were selected. Samples were collected in streams without fish farming and in streams with stretches used for fish farming, where collections took place both downstream and upstream. The fish were captured, identified, quantified and the water was collected for physical and chemical analyses, in addition to the environmental characterization that was carried out. Comparisons were made using fish richness and abundance indices between the sampled points and correspondence analysis of the species identified at the collection sites, using the Mantel test and principal component analysis (PCA) for the environmental characteristics of the water and variables physical and chemical, and permutational multivariate analysis of variance (PERMANOVA) to verify the possible effects of species composition on the sampled conditions and on the analyzed environmental variables. In total, 2,302 fish belonging to 53 species, 15 families and six orders were found. We conclude that the Amazonian streams dammed for fish farming, under the analyzed conditions, can be characterized as environments with different and specific levels of richness and abundance, however, the data set analyzed in this study did not show that these characteristics are directly related to productive activity. We recommend that further studies be carried out following the current research.

Ovarian development of Xiphopenaeus kroyeri (Crustacea: Penaeidae) from Espírito Santo, southeastern Brazil.

This study aimed to describe and characterize the stages of gonadal development of females of Xiphopenaeus kroyeri caught by artisanal fishers in Espírito Santo state, southeastern region of Brazil. All females (n= 1,831) were subjected to macroscopic and microscopic morphological analysis (n= 333) of the ovaries. From the morphology, coloration and degree of turgidity of the fresh ovary, macroscopic analysis determined five stages of gonadal development. The macroscopic analysis showed difficulties in differentiating the immature and spawning stages due to the similarity between the colors of the ovaries, which confirms the need to perform the macroscopic and histological analysis simultaneously for fisheries management studies. Microscopic observations allowed us to analyze the following six stages of cell development: oogonia, previtellogenic oocytes, primary vitellogenic oocytes, secondary vitellogenic oocytes, mature oocytes and atretic oocytes. From this, five stages of gonadal development were defined, i.e., immature, early development, advanced development, mature and spawned. The presence of peripheral bodies was not observed in this species. These results help to clarify and better understand the reproductive and population aspects of the Atlantic Seabob, which are fundamental for the establishment of management and conservation measures of this resource.

Influence of garlic extract on larval performance and survival of juvenile angelfish Pterophyllum scalare during transport / Influência do extrato de alho no desempenho larval e na sobrevivência durante o transporte de juvenis de acará bandeira Pterophyllum scalare

The objective of this study was to evaluate the properties of garlic as a growth promoter in larvae of angelfish Pterophyllum scalare and its benefits during transport of juveniles of this species. The experiment was conducted in recirculation aquaculture system, consisting of 20 tanks of 40 L equipped with independent water input and output. We used 1,400 larvae distributed among five treatments, with four repetitions, which totaled 20 experimental units. The treatments were 0, 50, 100, 200, and 400 mg of garlic extract per kilo of feed. The results showed that the inclusion of levels of garlic extract in the feed did not significantly effect the fish’s development or their transport. Neither did the inclusion of levels of garlic extract affect the survival of the larvae during the trial period. New research with extracts of higher dosages should be performed to elucidate the effect of garlic extract as a growth promoter.

O estudo teve como objetivo avaliar as propriedades do alho como promotor de crescimento em larvas de acará bandeira Pterophyllum scalare e seus benefícios no transporte de juvenis da mesma espécie. O experimento foi conduzido em sistema de recirculação composto por 20 aquários de 40 L de volume útil, dotado de entrada e saída de água independentes e teve a duração de 40 dias. O delineamento experimental adotado foi o inteiramente casualizado (DIC), com cinco tratamentos e quatro repetições, totalizando 20 unidades experimentais. Foram utilizadas 1.400 larvas de acará bandeira (Pterophyllum scalare) divididas entre os tratamentos. Os tratamentos consistiram em: 0, 50, 100, 200 e 400 mg de extrato de alho por quilo de ração. Os resultados mostraram que não houve efeito significativo dos níveis de inclusão do extrato do alho sobre os índices zootécnicos avaliados e posteriormente no transporte dos juvenis. Também não foi observado influência na sobrevivência das larvas durante o período experimental. Novas pesquisas com dosagens maiores de extratos devem ser realizados para melhor elucidação do efeito do extrato de alho como promotor de crescimento.

Influence of garlic extract on larval performance and survival of juvenile angelfish Pterophyllum scalare during transport

Abstract The objective of this study was to evaluate the properties of garlic as a growth promoter in larvae of angelfish Pterophyllum scalare and its benefits during transport of juveniles of this species. The experiment was conducted in recirculation aquaculture system, consisting of 20 tanks of 40 L equipped with independent water input and output. We used 1,400 larvae distributed among five treatments, with four repetitions, which totaled 20 experimental units. The treatments were 0, 50, 100, 200, and 400 mg of garlic extract per kilo of feed. The results showed that the inclusion of levels of garlic extract in the feed did not significantly effect the fishs development or their transport. Neither did the inclusion of levels of garlic extract affect the survival of the larvae during the trial period. New research with extracts of higher dosages should be performed to elucidate the effect of garlic extract as a growth promoter.

Resumo O estudo teve como objetivo avaliar as propriedades do alho como promotor de crescimento em larvas de acará bandeira Pterophyllum scalare e seus benefícios no transporte de juvenis da mesma espécie. O experimento foi conduzido em sistema de recirculação composto por 20 aquários de 40 L de volume útil, dotado de entrada e saída de água independentes e teve a duração de 40 dias. O delineamento experimental adotado foi o inteiramente casualizado (DIC), com cinco tratamentos e quatro repetições, totalizando 20 unidades experimentais. Foram utilizadas 1.400 larvas de acará bandeira (Pterophyllum scalare) divididas entre os tratamentos. Os tratamentos consistiram em: 0, 50, 100, 200 e 400 mg de extrato de alho por quilo de ração. Os resultados mostraram que não houve efeito significativo dos níveis de inclusão do extrato do alho sobre os índices zootécnicos avaliados e posteriormente no transporte dos juvenis. Também não foi observado influência na sobrevivência das larvas durante o período experimental. Novas pesquisas com dosagens maiores de extratos devem ser realizados para melhor elucidação do efeito do extrato de alho como promotor de crescimento.

Influence of garlic extract on larval performance and survival of juvenile angelfish Pterophyllum scalare during transport / Influência do extrato de alho no desempenho larval e na sobrevivência durante o transporte de juvenis de acará bandeira Pterophyllum scalare

Abstract The objective of this study was to evaluate the properties of garlic as a growth promoter in larvae of angelfish Pterophyllum scalare and its benefits during transport of juveniles of this species. The experiment was conducted in recirculation aquaculture system, consisting of 20 tanks of 40 L equipped with independent water input and output. We used 1,400 larvae distributed among five treatments, with four repetitions, which totaled 20 experimental units. The treatments were 0, 50, 100, 200, and 400 mg of garlic extract per kilo of feed. The results showed that the inclusion of levels of garlic extract in the feed did not significantly effect the fish's development or their transport. Neither did the inclusion of levels of garlic extract affect the survival of the larvae during the trial period. New research with extracts of higher dosages should be performed to elucidate the effect of garlic extract as a growth promoter.

Resumo O estudo teve como objetivo avaliar as propriedades do alho como promotor de crescimento em larvas de acará bandeira Pterophyllum scalare e seus benefícios no transporte de juvenis da mesma espécie. O experimento foi conduzido em sistema de recirculação composto por 20 aquários de 40 L de volume útil, dotado de entrada e saída de água independentes e teve a duração de 40 dias. O delineamento experimental adotado foi o inteiramente casualizado (DIC), com cinco tratamentos e quatro repetições, totalizando 20 unidades experimentais. Foram utilizadas 1.400 larvas de acará bandeira (Pterophyllum scalare) divididas entre os tratamentos. Os tratamentos consistiram em: 0, 50, 100, 200 e 400 mg de extrato de alho por quilo de ração. Os resultados mostraram que não houve efeito significativo dos níveis de inclusão do extrato do alho sobre os índices zootécnicos avaliados e posteriormente no transporte dos juvenis. Também não foi observado influência na sobrevivência das larvas durante o período experimental. Novas pesquisas com dosagens maiores de extratos devem ser realizados para melhor elucidação do efeito do extrato de alho como promotor de crescimento.

Socioeconomic aspects and profile of fishing according to fishers of commercial edible fish in the municipality of Barcelos, middle Negro River, Amazonas, Brazil.

Fishing plays a prominent role in the socioeconomic scope of the Negro River basin and is considered one of the main extractive activities in the region. The objective of this study was to describe the socioeconomic aspects of commercial fishers of edible fish who work in the municipality of Barcelos, in the middle Negro River region, as well as to highlight the scenario of the fishing activity from the point of view of the fishers. The information was collected between January and December 2016 in the municipality of Barcelos, state of Amazonas, via semi-structured questionnaires. Most interviewees were male (71.14%), aged between 18 and 82 years and a mean age of 48 years. With a low level of education, 45.0% had only incomplete elementary education and 15% were illiterate. The fishing tackle most used by fishermen was the gillnet, especially by urban fishermen (70%). Among the fishing sites, the main one was the Demeni River (50%). Commercial fishing for edible fish in Barcelos focused on Characiformes, Perciformes and Siluriformes fish. The main difficulties faced by the activity are related to the seasonality of the level of rivers and local tributaries, as well as the lack of buyers and low selling price of fish, in addition to conflicts over the use of fishing resources. Commercial fishing for edible fish is an activity of great socioeconomic importance for riverside families in the Middle River Negro basin, which needs greater attention from the public authorities. Therefore, it is expected that the information contained in this study can help in the decision-making process for the management of local fisheries resources and contribute to the resumption of growth and sustainability of commercial edible fish fisheries.

Zootechnical indices and digestibility in juveniles of tambaqui Colossoma macropomum fed a diet containing particulate maize / Índices zootécnicos e digestibilidade em juvenis de tambaqui Colossoma macropomum alimentados com dieta contendo milho particulado

Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 μm) had better results digestibility. Smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 μm of corn be used for tambaqui.

Três experimentos foram realizados com diferentes tamanhos de partícula de ração para o desempenho zootécnico, taxa de aprovação e digestibilidade aparente de tambaqui juvenil (Colossoma macropomum). No primeiro, foram utilizados 200 juvenis e distribuídos em 20 tanques (220 L), 10 peixes por unidade (quatro repetições). O sistema experimental utilizado para registrar o tempo de passagem foi composto por cinco incubadoras com 200 L. No segundo, 75 juvenis foram utilizados por 55 dias (três repetições). No terceiro, 75 juvenis foram utilizados e distribuídos em cinco incubadoras de 200 L. Todos os experimentos foram realizados aleatoriamente. Diferentes tratamentos de comportamento linear foram observados para digestibilidade aparente da proteína bruta; e o menor tamanho de partícula (150 μm) apresentou melhor digestibilidade dos resultados. menor tamanho de partícula do milho apresentou melhores resultados, afetou o desempenho de crescimento de tambaquis e a digestibilidade aparente da proteína bruta e extrato etéreo. Portanto, recomenda-se o uso de um tamanho de partícula de 150 μm de milho para o tambaqui.

Trophic relationships among three species of ornamental fish from the region of Lake Amanã, Amazon / Relações tróficas entre três espécies de peixes ornamentais da região do lago de Amanã, Amazonas

The present study objectified to evaluate the trophic relationships and the possible aggressive mimicry involving Carnegiella strigata, Carnegiella marthae and Gnathocharax steindachneri, in lowland forest streams. Samplings occurred in November 2002, March and August 2003 in Amanã Sustainable Development Reserve (ASDR). The total of 943 fish was caught, being 79.43% of C. marthae, 3.18% of C. strigata and 17.39% of G. steindachneri. Stomach contents, degree of stomach repletion, relative volume and frequency of occurrence of food items were evaluated. Thirteen food items were identified, and the presence of terrestrial and aquatic insects indicates the high dependence of these species and the flooded forest. Low feeding overlap was observed between Carnegiella strigata and C. marthae compared to Gnathocharax steindachneri. However, the overlap between the two Carnegiella species was relatively high, which could explain the low frequency of syntopic occurrence among these species, suggesting a possible case of competitive exclusion.

Este estudo teve como objetivo analisar as relações tróficas e a possível existência de uma relação de mimetismo agressivo envolvendo Carnegiella strigata, Carnegiella marthae e Gnathocharax steindachneri, em igarapés de terra firme. As coletas ocorreram em novembro de 2002, março e agosto de 2003 e foram realizadas na Reserva de Desenvolvimento Sustentável de Amanã (RDSA). Foram capturados 943 peixes, onde C. marthae representou 79,43%, C. strigata 3,18% e G. steindachneri 17,39%. Foram analisados os conteúdos estomacais e verificados grau de repleção, volume relativo e frequência de ocorrência dos alimentos. Foram identificados 13 itens alimentares, onde insetos terrestres e aquáticos denotaram alto grau de dependência destas espécies em relação à floresta alagada. Ocorreu baixa sobreposição alimentar das espécies Carnegiella strigata e C. marthae em relação a Gnathocharax steindachneri. Entretanto, a sobreposição entre as duas espécies de Carnegiella foi relativamente alta, o que poderia explicar a baixa frequência de ocorrência sintópica entre essas espécies, sugerindo um possível caso de exclusão competitiva.

Zootechnical indices and digestibility in juveniles of tambaqui Colossoma macropomum fed a diet containing particulate maize

Abstract Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 m) had better results digestibility. smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 m of corn be used for tambaqui.

Resumo Três experimentos foram realizados com diferentes tamanhos de partícula de ração para o desempenho zootécnico, taxa de aprovação e digestibilidade aparente de tambaqui juvenil (Colossoma macropomum). No primeiro, foram utilizados 200 juvenis e distribuídos em 20 tanques (220 L), 10 peixes por unidade (quatro repetições). O sistema experimental utilizado para registrar o tempo de passagem foi composto por cinco incubadoras com 200 L. No segundo, 75 juvenis foram utilizados por 55 dias (três repetições). No terceiro, 75 juvenis foram utilizados e distribuídos em cinco incubadoras de 200 L. Todos os experimentos foram realizados aleatoriamente. Diferentes tratamentos de comportamento linear foram observados para digestibilidade aparente da proteína bruta; e o menor tamanho de partícula (150 m) apresentou melhor digestibilidade dos resultados. menor tamanho de partícula do milho apresentou melhores resultados, afetou o desempenho de crescimento de tambaquis e a digestibilidade aparente da proteína bruta e extrato etéreo. Portanto, recomenda-se o uso de um tamanho de partícula de 150 m de milho para o tambaqui.

Trophic relationships among three species of ornamental fish from the region of Lake Amanã, Amazon

Abstract The present study objectified to evaluate the trophic relationships and the possible aggressive mimicry involving Carnegiella strigata, Carnegiella marthae and Gnathocharax steindachneri, in lowland forest streams. Samplings occurred in November 2002, March and August 2003 in Amanã Sustainable Development Reserve (ASDR). The total of 943 fish was caught, being 79.43% of C. marthae, 3.18% of C. strigata and 17.39% of G. steindachneri. Stomach contents, degree of stomach repletion, relative volume and frequency of occurrence of food items were evaluated. Thirteen food items were identified, and the presence of terrestrial and aquatic insects indicates the high dependence of these species and the flooded forest. Low feeding overlap was observed between Carnegiella strigata and C. marthae compared to Gnathocharax steindachneri. However, the overlap between the two Carnegiella species was relatively high, which could explain the low frequency of syntopic occurrence among these species, suggesting a possible case of competitive exclusion.

Resumo Este estudo teve como objetivo analisar as relações tróficas e a possível existência de uma relação de mimetismo agressivo envolvendo Carnegiella strigata, Carnegiella marthae e Gnathocharax steindachneri, em igarapés de terra firme. As coletas ocorreram em novembro de 2002, março e agosto de 2003 e foram realizadas na Reserva de Desenvolvimento Sustentável de Amanã (RDSA). Foram capturados 943 peixes, onde C. marthae representou 79,43%, C. strigata 3,18% e G. steindachneri 17,39%. Foram analisados os conteúdos estomacais e verificados grau de repleção, volume relativo e frequência de ocorrência dos alimentos. Foram identificados 13 itens alimentares, onde insetos terrestres e aquáticos denotaram alto grau de dependência destas espécies em relação à floresta alagada. Ocorreu baixa sobreposição alimentar das espécies Carnegiella strigata e C. marthae em relação a Gnathocharax steindachneri. Entretanto, a sobreposição entre as duas espécies de Carnegiella foi relativamente alta, o que poderia explicar a baixa frequência de ocorrência sintópica entre essas espécies, sugerindo um possível caso de exclusão competitiva.

Trophic relationships among three species of ornamental fish from the region of Lake Amanã, Amazon / Relações tróficas entre três espécies de peixes ornamentais da região do lago de Amanã, Amazonas

The present study objectified to evaluate the trophic relationships and the possible aggressive mimicry involving Carnegiella strigata, Carnegiella marthae and Gnathocharax steindachneri, in lowland forest streams. Samplings occurred in November 2002, March and August 2003 in Amanã Sustainable Development Reserve (ASDR). The total of 943 fish was caught, being 79.43% of C. marthae, 3.18% of C. strigata and 17.39% of G. steindachneri. Stomach contents, degree of stomach repletion, relative volume and frequency of occurrence of food items were evaluated. Thirteen food items were identified, and the presence of terrestrial and aquatic insects indicates the high dependence of these species and the flooded forest. Low feeding overlap was observed between Carnegiella strigata and C. marthae compared to Gnathocharax steindachneri. However, the overlap between the two Carnegiella species was relatively high, which could explain the low frequency of syntopic occurrence among these species, suggesting a possible case of competitive exclusion.

Este estudo teve como objetivo analisar as relações tróficas e a possível existência de uma relação de mimetismo agressivo envolvendo Carnegiella strigata, Carnegiella marthae e Gnathocharax steindachneri, em igarapés de terra firme. As coletas ocorreram em novembro de 2002, março e agosto de 2003 e foram realizadas na Reserva de Desenvolvimento Sustentável de Amanã (RDSA). Foram capturados 943 peixes, onde C. marthae representou 79,43%, C. strigata 3,18% e G. steindachneri 17,39%. Foram analisados os conteúdos estomacais e verificados grau de repleção, volume relativo e frequência de ocorrência dos alimentos. Foram identificados 13 itens alimentares, onde insetos terrestres e aquáticos denotaram alto grau de dependência destas espécies em relação à floresta alagada. Ocorreu baixa sobreposição alimentar das espécies Carnegiella strigata e C. marthae em relação a Gnathocharax steindachneri. Entretanto, a sobreposição entre as duas espécies de Carnegiella foi relativamente alta, o que poderia explicar a baixa frequência de ocorrência sintópica entre essas espécies, sugerindo um possível caso de exclusão competitiva.

Zootechnical indices and digestibility in juveniles of tambaqui Colossoma macropomum fed a diet containing particulate maize / Índices zootécnicos e digestibilidade em juvenis de tambaqui Colossoma macropomum alimentados com dieta contendo milho particulado

Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 µm) had better results digestibility. smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 µm of corn be used for tambaqui.

Três experimentos foram realizados com diferentes tamanhos de partícula de ração para o desempenho zootécnico, taxa de aprovação e digestibilidade aparente de tambaqui juvenil (Colossoma macropomum). No primeiro, foram utilizados 200 juvenis e distribuídos em 20 tanques (220 L), 10 peixes por unidade (quatro repetições). O sistema experimental utilizado para registrar o tempo de passagem foi composto por cinco incubadoras com 200 L. No segundo, 75 juvenis foram utilizados por 55 dias (três repetições). No terceiro, 75 juvenis foram utilizados e distribuídos em cinco incubadoras de 200 L. Todos os experimentos foram realizados aleatoriamente. Diferentes tratamentos de comportamento linear foram observados para digestibilidade aparente da proteína bruta; e o menor tamanho de partícula (150 µm) apresentou melhor digestibilidade dos resultados. menor tamanho de partícula do milho apresentou melhores resultados, afetou o desempenho de crescimento de tambaquis e a digestibilidade aparente da proteína bruta e extrato etéreo. Portanto, recomenda-se o uso de um tamanho de partícula de 150 µm de milho para o tambaqui.

Growth and hematological responses of tambaqui, Colossoma macropomum fed different levels of rice, Oryza spp / Crescimento e resposta hematológica do tambaqui, Colossoma macropomum alimentados com diferentes níveis de arroz, Oryza spp

Abstract The tambaqui (Colossoma macropomum) is a fish of primary importance in South American aquaculture, principally in the Amazon region and has a particularly unique diet in the wild. Oryza spp, or Wild rice as it is commonly known, is native to the floodplains of muddy rivers in the Amazon region. The aim of this study was to analyze the physical performance and the effects of dietary levels of Oryza spp. via the hematological parameters, total food intake, conversion efficiency, growth ratio and swimming performance of this fish. Diets containing 45% Oryza spp. induced the best performance in tambaqui. Diets containing 15% and 30% did not affect these indices, thus indicating that this amount of Oryza can be used as an alternative energy source for this important species within Brazilian aquaculture.

Resumo O tambaqui Colossoma macropomum é um peixe de importância na aquicultura brasileira, especialmente na região amazônica. O arroz silvestre é comum nas planícies inundadas dos rios de aguas barrentas da Amazônia. O objetivo deste trabalho foi analisar os efeitos combinados do treinamento físico e dos níveis dietéticos de Oryza spp. nos parâmetros hematológicos, consumo de alimentos, eficiência de conversão, taxa de crescimento e desempenho de natação deste peixe. Dietas contendo 45% de arroz apresentaram o melhor desempenho para tambaquis. As dietas contendo 15% e 30% não afetaram esses índices, indicando que alguma quantidade de arroz pode ser usada como fonte de energia alternativa para esta importante espécie dentro da aquicultura.

Influence of garlic extract on larval performance and survival of juvenile angelfish Pterophyllum scalare during transport.

The objective of this study was to evaluate the properties of garlic as a growth promoter in larvae of angelfish Pterophyllum scalare and its benefits during transport of juveniles of this species. The experiment was conducted in recirculation aquaculture system, consisting of 20 tanks of 40 L equipped with independent water input and output. We used 1,400 larvae distributed among five treatments, with four repetitions, which totaled 20 experimental units. The treatments were 0, 50, 100, 200, and 400 mg of garlic extract per kilo of feed. The results showed that the inclusion of levels of garlic extract in the feed did not significantly effect the fish's development or their transport. Neither did the inclusion of levels of garlic extract affect the survival of the larvae during the trial period. New research with extracts of higher dosages should be performed to elucidate the effect of garlic extract as a growth promoter.

Trophic relationships among three species of ornamental fish from the region of Lake Amanã, Amazon.

The present study objectified to evaluate the trophic relationships and the possible aggressive mimicry involving Carnegiella strigata, Carnegiella marthae and Gnathocharax steindachneri, in lowland forest streams. Samplings occurred in November 2002, March and August 2003 in Amanã Sustainable Development Reserve (ASDR). The total of 943 fish was caught, being 79.43% of C. marthae, 3.18% of C. strigata and 17.39% of G. steindachneri. Stomach contents, degree of stomach repletion, relative volume and frequency of occurrence of food items were evaluated. Thirteen food items were identified, and the presence of terrestrial and aquatic insects indicates the high dependence of these species and the flooded forest. Low feeding overlap was observed between Carnegiella strigata and C. marthae compared to Gnathocharax steindachneri. However, the overlap between the two Carnegiella species was relatively high, which could explain the low frequency of syntopic occurrence among these species, suggesting a possible case of competitive exclusion.

Zootechnical indices and digestibility in juveniles of tambaqui Colossoma macropomum fed a diet containing particulate maize.

Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 µm) had better results digestibility. smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 µm of corn be used for tambaqui.

Hematological parameters of three species of the peacock bass (Cichla spp. ) from Balbina lake, Presidente Figueiredo, Amazonas, Brazil / Parâmetros hematológicos de três espécies de tucunarés (Cichla spp. ) do lago de Balbina, Presidente Figueiredo, Amazonas, Brasil

Abstract The objective of this study was to characterize and compare the hematological variables (erythrogram, thrombogram, leukogram and plasma metabolites) of three cichlid species: Cichla monoculus, Cichla temensis and Cichla vazzoleri. A total of 45 specimens were captured in Balbina lake, Presidente Figueiredo, Amazonas, Brazil, with the aid of a rod and reel or hand line, with natural or artificial bait: 15 C. monoculus, 15 C. temensis and 15 C. vazzoleri. Their blood was removed by means of caudal puncture of the dorsal aorta, and hematological data were determined in accordance with methodology previously described in the literature. The erythrogram showed similarities between the species, while the thrombogram showed differences between C. vazzoleri and the other species studied (C. monoculus and C. temensis). The total leukocyte counts for C. temensis and C. vazzoleri were higher than those of C. monoculus. The predominant leukocyte in C. temensis and C. vazzoleri was lymphocytes, whereas it was monocytes in C. monoculus. The plasma metabolites showed differences between the three cichlid species, regarding their glucose, cholesterol, urea and potassium levels. It is concluded that these three species present hematological differentiation, thus indicating that they have differentiated blood-cell immune responses and plasma metabolite physiology.

Resumo O presente trabalho teve por objetivo caracterizar e comparar as variáveis hematológicas (eritrograma, trombograma, leucograma e metabólitos plasmáticos) de três espécies de tucunarés Cichla monoculus, Cichla temensis e Cichla vazzoleri. Um total de 45 animais foi capturado no lago de Balbina, Presidente Figueiredo, Amazonas, com auxílio de vara e carretilha, linha de mão com isca natural e artificial, sendo 15 C. monoculos, 15 C. temensis e 15 C. vazzoleri. O sangue foi retirado por punção caudal da aorta dorsal e os dados hematológicos foram determinados de acordo com metodologia previamente descrita na literatura. No eritrograma foram observadas similaridades entre as espécies, o trombograma demonstrou diferenças entre o C. vazzoleri e as demais espécies estudadas (C. monoculus e C. temensis), a contagem total de leucócitos demonstrou que em C. temensis e C. vazzoleri os valores são superiores ao C. monoculus. Foi demonstrado que os linfócitos foram às células predominantes em C. temensis e C. vazzoleri, diferentemente do C. monoculos que apresentou como leucócito predominante os monócitos. Nos metabólitos plasmáticos, foi possível observar diferenças entre as três espécies de tucunarés nos níveis de glicose, colesterol, uréia e potássio. Conclui-se que as três espécies de tucunarés apresentam diferenciação hematológica, indicando que as mesmas possuem respostas diferenciadas, na resposta imunológica de suas células do sangue e na fisiologia dos metabólitos plasmáticos.

Hematological parameters of three species of the peacock bass (Cichla spp.) from Balbina lake, Presidente Figueiredo, Amazonas, Brazil.

The objective of this study was to characterize and compare the hematological variables (erythrogram, thrombogram, leukogram and plasma metabolites) of three cichlid species: Cichla monoculus, Cichla temensis and Cichla vazzoleri. A total of 45 specimens were captured in Balbina lake, Presidente Figueiredo, Amazonas, Brazil, with the aid of a rod and reel or hand line, with natural or artificial bait: 15 C. monoculus, 15 C. temensis and 15 C. vazzoleri. Their blood was removed by means of caudal puncture of the dorsal aorta, and hematological data were determined in accordance with methodology previously described in the literature. The erythrogram showed similarities between the species, while the thrombogram showed differences between C. vazzoleri and the other species studied (C. monoculus and C. temensis). The total leukocyte counts for C. temensis and C. vazzoleri were higher than those of C. monoculus. The predominant leukocyte in C. temensis and C. vazzoleri was lymphocytes, whereas it was monocytes in C. monoculus. The plasma metabolites showed differences between the three cichlid species, regarding their glucose, cholesterol, urea and potassium levels. It is concluded that these three species present hematological differentiation, thus indicating that they have differentiated blood-cell immune responses and plasma metabolite physiology.

Growth and hematological responses of tambaqui, Colossoma macropomum fed different levels of rice, Oryza spp.

The tambaqui (Colossoma macropomum) is a fish of primary importance in South American aquaculture, principally in the Amazon region and has a particularly unique diet in the wild. Oryza spp, or Wild rice as it is commonly known, is native to the floodplains of muddy rivers in the Amazon region. The aim of this study was to analyze the physical performance and the effects of dietary levels of Oryza spp. via the hematological parameters, total food intake, conversion efficiency, growth ratio and swimming performance of this fish. Diets containing 45% Oryza spp. induced the best performance in tambaqui. Diets containing 15% and 30% did not affect these indices, thus indicating that this amount of Oryza can be used as an alternative energy source for this important species within Brazilian aquaculture.

Ornamental fishing in the region of Barcelos, Amazonas: socioeconomic description and scenario of activity in the view of piabeiros / A pesca ornamental na região de Barcelos, Amazonas: descrição socieconômica e cenário da atividade na visão dos piabeiros

Abstract The Negro river basin is considered the largest area of extractive of ornamental fish in Brazil. This area has fundamental importance for the populations from the Amazon. The present study aimed to describe socioeconomic profile of ornamental fishermen known as "piabeiros" in the Municipality of Barcelos, as well as the ornamental fishery, fisheries area, target species, environments, fishing techniques, equipment, capture techniques and main difficulties faced by the current activity. This study was carried out in municipality of Barcelos, through semi - structured interviews, with artisanal ornamental fishermen (N= 89). The main families of ornamental fish caught and traded were: Characidae, Lebiasinidae, Gasteropelecidae, Cichilidae, Anostomidae, Loricaridae, Potamotrygonidae and Gymnotidae. The main catchment areas were igarapés, lakes, flooded fields, beaches, river banks and igapó forest. Rapiché was the most used equipment in the fisheries both by the fishermen of the urban areas (43.81%) and rural (41.89%). Most of the fishermen are associated with the colony of fishermen of Barcelos (Z33). The data showed that the dynamics of ornamental fishing have changed in a short time and directly affected fishermen, in addition to the low age renewal with the participation of younger fishermen, threatening the transmission of ecological knowledge to future generations. As a result, the increase of the problems related to the productive chain and absence of public power to the activity, since ornamental fishing has already been treated as one of the main economic activities more important for the local communities and for the State of Amazonas.

Resumo A bacia do rio Negro é considerada a maior área de extrativismo de peixes ornamentais do Brasil. Esta área possui importância fundamental para as populações da Amazônia. O presente estudo objetivou descrever o perfil socioeconômico de pescadores conhecidos como "piabeiros" no município de Barcelos, bem como a pesca ornamental, área de pesca, espécies-alvo, ambientes, técnicas de pesca, equipamentos, técnicas de captura e dificuldades enfrentadas nesta atividade. O estudo foi realizado por meio de entrevistas semi - estruturadas, com pescadores artesanais ornamentais (N= 89). Os dados mostram que as famílias de peixes ornamentais capturados e comercializados foram: Characidae, Lebiasinidae, Gasteropelecidae, Cichilidae, Anostomidae, Loricaridae, Potamotrygonidae e Gymnotidae. As áreas de captura descritas foram igarapés, lagos, alagados, praias, margens de rios e floresta de igapó. O Rapiché foi o equipamento mais utilizado nas pescarias tanto pelos pescadores das áreas urbanas (43,81%) como rurais (41,89%). A maioria dos pescadores está associada à colônia de pescadores de Barcelos (Z33). Os dados coletados mostraram que a dinâmica da pesca ornamental mudou em pouco tempo e afetou diretamente os pescadores. Além da baixa taxa de renovação, com a participação de pescadores mais jovens, ameaçando a transmissão de conhecimento ecológico para as gerações futuras. Como resultado, notamos o aumento dos problemas relacionados à cadeia produtiva e a ausência de poder público na atividade. A pesca ornamental já foi tratada como uma das principais atividades econômicas para as comunidades locais e para o Estado do Amazonas.