Feeding protocol for the Amazonian ornamental cichlid Apistogramma cacatuoides and a histological approach to the nutritional condition of larvae.

The aim of this study was to develop a feeding protocol for the larviculture of Apistogramma cacatuoides, using the histological approach to larval nutrition conditions. For this, three experiments were carried out. Experiment 1 was carried out in a randomized design to determine the optimal amount of Artemia nauplii (AN) per larva, and three treatments were evaluated: P1-feeding with 25 A. nauplii per larva (AN/L) during the first 5 days, followed by 50 AN/L from the 6th to the 10th day and 100 AN/L from the 11th to the 20th day; P2 and P3-37 and 50 AN/L during the first 5 days, 75 and 100 AN/L from the 6th to the 10th day and 150 and 200 AN/L from the 11th to the 20th day. Experiment 2 was carried out in a randomized design to determine the daily frequency of feeding and evaluated four feeding frequencies: F1-feeding only once a day (09:00); (F2)-feeding twice a day (09:00 and 17:00); F3-feeding three times a day (09:00, 11:30 and 17:00); and F4-feeding four times a day (09:00, 11: 30, 14:00 and 17:00). Experiment 3 lasted 40 days and was conducted in a randomized design to evaluate three periods for the beginning of the feeding transition: WE10:AN for 10 days, followed by 3 days of co-feeding and commercial feed until the end of the experimental period; WE15:AN for 15 days, followed by 3 days of co-feeding and commercial feed; WE20:AN for 20 days, followed by 3 days of co-feeding and commercial feed. The results of this study showed that, for the best development of the larvae, they should receive the feeding protocol 50-100-200 AN/L (P3) until the 20th day of exogenous feeding. From the 21st day, the transition to inert food should begin with 3 days of co-feeding, and feeding during larviculture should be carried out at a frequency of twice a day; this protocol provided a good nutritional status for the larvae, as shown by the histological approach.

Salinity and prey concentration on larviculture of killifish Hypsolebias radiseriatus (Cyprinodontiformes: Rivulidae)

The aim of this study was to investigate the tolerance of Hypsolebias radiseriatuslarvae to different salinities, and the effects of different prey concentrations and water salinities on the larviculture of this species. Salinity tolerance was tested by subjecting newly-hatched larvae to 96 hours of osmotic shock testing (experiment I) and gradual acclimatization (experiment II) of the following salinities: freshwater (control), 2, 4, 6 and 8 g of salt L-1. A third experiment (experiment III) evaluated three water salinities (S0-freshwater, S2-2 g of salt L-1and S4–4 g of salt L-1) and three initial daily prey concentrations (100, 300 and 500 artemia nauplii larva-1). In experiments I and II, survival was only influenced by the salinity of 8 g of salt L-1(p < 0.01). After 35 days, weight was only influenced by prey concentration (p < 0.05), with the highest value being with 500 artemia nauplii larva-1. The lowest survival was for 4 g of salt L-1and for 100 artemia nauplii larva-1. H. radiseriatuslarviculture can be carried out in salinity of up to 2 g of salt L-1and initial daily prey concentrations with 500 artemia nauplii larva-1.(AU)

Salinity and prey concentration on larviculture of killifish Hypsolebias radiseriatus (Cyprinodontiformes: Rivulidae)

The aim of this study was to investigate the tolerance of Hypsolebias radiseriatuslarvae to different salinities, and the effects of different prey concentrations and water salinities on the larviculture of this species. Salinity tolerance was tested by subjecting newly-hatched larvae to 96 hours of osmotic shock testing (experiment I) and gradual acclimatization (experiment II) of the following salinities: freshwater (control), 2, 4, 6 and 8 g of salt L-1. A third experiment (experiment III) evaluated three water salinities (S0-freshwater, S2-2 g of salt L-1and S4–4 g of salt L-1) and three initial daily prey concentrations (100, 300 and 500 artemia nauplii larva-1). In experiments I and II, survival was only influenced by the salinity of 8 g of salt L-1(p < 0.01). After 35 days, weight was only influenced by prey concentration (p < 0.05), with the highest value being with 500 artemia nauplii larva-1. The lowest survival was for 4 g of salt L-1and for 100 artemia nauplii larva-1. H. radiseriatuslarviculture can be carried out in salinity of up to 2 g of salt L-1and initial daily prey concentrations with 500 artemia nauplii larva-1.

Diferentes estratégias alimentares na larvicultura do acará-bandeira (Peterolophyllum scalare,Cichlidae) / Different feeding strategies on larval rearing of angelfish (Peterolophyllum scalare, Cichlidae)

The hatchery is one of the most critical stages of the development of fish and their success is directly related to food handling that can provide greater survival and growth. The aim of this study was to evaluate the time of dietary transition and providing meta-nauplii of Artemia spp. (MNA) for the angelfish larvae. Two experiments were conducted in a completely randomized design with five treatments and four repetitions. On each experiment there were used 540 fishes, distributed in 20 tanks with 2 liters each. In the first experiment, there were evaluated the dietary transition periods (MNA + Diet) for 1, 2, 3, 4 and 5 days. In the second experiment, there were evaluated the supply of MNA for 5, 10, 15, 20 and 25 days. There were evaluated: weight gain, growth rate and specific development, survival and batch uniformity (only in the experiment to evaluate the time of fish feed with MNA). There was no significant effect of different periods of dietary transition on the growth variables (p>0.05), but survival was higher (p<0.05) in the treatments composed of 3, 4 and 5 days of joint feed. In relation to the time of supply of MNA worse results were observed (p<0.05) when the time of supply of live food was shorter (5, 10 and 15 days). The animals were fed with MNA before feeding transition, for longer time (20 and 25) showed the best results for growth (p<0.05). Therefore, a food transition of three days and a supply of MNA for 20 days is recommended to perform the total replacement of live food for feed.

A larvicultura é uma das etapas mais críticas do desenvolvimento dos peixes e o seu sucesso está diretamente relacionado ao manejo alimentar, que pode proporcionar maiores sobrevivência e crescimento. Objetivou-se avaliar o tempo de transição alimentar e de fornecimento de meta-náuplios de Artemia spp (MNA) na larvicultura do acará-bandeira. Dois experimentos foram conduzidos em delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Em cada experimento foram utilizados 540 peixes distribuídos em 20 aquários com 2 L. No primeiro experimento, avaliaram-se os períodos de transição alimentar (MNA + ração) por 1, 2, 3, 4 e 5 dias. No segundo experimento, avaliou-se o período de fornecimento de MNA por 5, 10, 15, 20 e 25 dias. Foram avaliados: ganho de peso, taxas de crescimento e desenvolvimento específico, sobrevivência e uniformidade do lote (apenas no experimento para avaliar o tempo de fornecimento de MNA). Não houve efeito significativo dos diferentes períodos de transição alimentar sobre as variáveis de crescimento (p>0,05), porém a sobrevivência foi maior (p<0,05) nos tratamentos compostos por 3, 4 e 5 dias de alimentação conjunta. Em relação ao tempo de fornecimento de MNA, foram observados piores resultados (p<0,05) quando o tempo de fornecimento do alimento vivo foi menor (5, 10 e 15 dias). Os animais que foram alimentados com MNA antes da transição alimentar, por mais tempo (20 e 25 dias), apresentaram os melhores resultados de crescimento (p<0,05). Portanto, recomenda-se uma transição alimentar de três dias e um fornecimento de MNA por 20 dias para realizar a substituição total do alimento vivo pela ração.

Diferentes estratégias alimentares na larvicultura do acará-bandeira (Peterolophyllum scalare,Cichlidae) / Different feeding strategies on larval rearing of angelfish (Peterolophyllum scalare, Cichlidae)

The hatchery is one of the most critical stages of the development of fish and their success is directly related to food handling that can provide greater survival and growth. The aim of this study was to evaluate the time of dietary transition and providing meta-nauplii of Artemia spp. (MNA) for the angelfish larvae. Two experiments were conducted in a completely randomized design with five treatments and four repetitions. On each experiment there were used 540 fishes, distributed in 20 tanks with 2 liters each. In the first experiment, there were evaluated the dietary transition periods (MNA + Diet) for 1, 2, 3, 4 and 5 days. In the second experiment, there were evaluated the supply of MNA for 5, 10, 15, 20 and 25 days. There were evaluated: weight gain, growth rate and specific development, survival and batch uniformity (only in the experiment to evaluate the time of fish feed with MNA). There was no significant effect of different periods of dietary transition on the growth variables (p>0.05), but survival was higher (p<0.05) in the treatments composed of 3, 4 and 5 days of joint feed. In relation to the time of supply of MNA worse results were observed (p<0.05) when the time of supply of live food was shorter (5, 10 and 15 days). The animals were fed with MNA before feeding transition, for longer time (20 and 25) showed the best results for growth (p<0.05). Therefore, a food transition of three days and a supply of MNA for 20 days is recommended to perform the total replacement of live food for feed.(AU)

A larvicultura é uma das etapas mais críticas do desenvolvimento dos peixes e o seu sucesso está diretamente relacionado ao manejo alimentar, que pode proporcionar maiores sobrevivência e crescimento. Objetivou-se avaliar o tempo de transição alimentar e de fornecimento de meta-náuplios de Artemia spp (MNA) na larvicultura do acará-bandeira. Dois experimentos foram conduzidos em delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Em cada experimento foram utilizados 540 peixes distribuídos em 20 aquários com 2 L. No primeiro experimento, avaliaram-se os períodos de transição alimentar (MNA + ração) por 1, 2, 3, 4 e 5 dias. No segundo experimento, avaliou-se o período de fornecimento de MNA por 5, 10, 15, 20 e 25 dias. Foram avaliados: ganho de peso, taxas de crescimento e desenvolvimento específico, sobrevivência e uniformidade do lote (apenas no experimento para avaliar o tempo de fornecimento de MNA). Não houve efeito significativo dos diferentes períodos de transição alimentar sobre as variáveis de crescimento (p>0,05), porém a sobrevivência foi maior (p<0,05) nos tratamentos compostos por 3, 4 e 5 dias de alimentação conjunta. Em relação ao tempo de fornecimento de MNA, foram observados piores resultados (p<0,05) quando o tempo de fornecimento do alimento vivo foi menor (5, 10 e 15 dias). Os animais que foram alimentados com MNA antes da transição alimentar, por mais tempo (20 e 25 dias), apresentaram os melhores resultados de crescimento (p<0,05). Portanto, recomenda-se uma transição alimentar de três dias e um fornecimento de MNA por 20 dias para realizar a substituição total do alimento vivo pela ração.(AU)

Corn granulometry in diets for tambaqui juvenile / Granulometria do milho em rações para juvenis de tambaqui

This study aimed to evaluate the performance, carcass composition and viability of different corn granulometry (CG) in diets for tambaqui. It was distributed 160 fish (3.86±0.03g) into 20 aquaria (40-L) in a completely randomized design with five treatments and four replications. The treatments consisted of diets with different CG: 150, 300, 500, 710 and 850 µm. As performance parameters were evaluated: feed intake (FI), weight gain (WG), feed conversion rate (FCR),  final total length (FTL), final standard length (FSL), height (H), specific growth rate (SGR), specific development rate (SDR) and survival (SUR). For carcass composition were evaluated moisture, crude protein, ether extract and mineral matter. For the economic analysis of diet were analyzed the total cost of production (TCP), cost of feed per kg weight gain (CFK) and the index of economic efficiency (IEE). Data were subjected to analysis of variance at 5% probability and polynomial regression. There was quadratic effect for the variables FI, WG, FCR, FTL, FSL, H, SGR and SDR, obtaining the best results, respectively, for CG estimated at 530.22; 555.40; 597.47; 566.75; 562.07; 557.48; 562.70 e 555.68 µm. There was no influence of CG on the carcass composition. There was quadratic effect for TCP and CFK variables, with higher values for CG estimated at, respectively, 600.44 and 602.11 µm.(AU)

Objetivou-se avaliar diferentes granulometrias do milho (GM) em rações para juvenis de tambaqui sobre o desempenho zootécnico, composição da carcaça e viabilidade econômica. Foram distribuídos 160 peixes (3,86±0,03 g) em 20 aquários (40 L), em delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Os tratamentos consistiram de rações com diferentes GM: 150, 300, 500, 710 e 850 µm. Como parâmetros de desempenho zootécnico foram avaliados: consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), comprimento total final (CTF), comprimento padrão final (CPF), altura final (ALT), taxa de crescimento específico (TCE), taxa de desenvolvimento específico (TDE) e sobrevivência (SOB). Para composição de carcaça foram avaliados umidade, proteína bruta, extrato etéreo e matéria mineral. Na análise econômica das rações, foram analisados o custo médio com ração por quilograma de peso vivo ganho (CMR), o custo total de produção (CTP) e o índice de eficiência econômica (IEE). Os dados obtidos foram submetidos à análise de variância em nível de 5% de probabilidade e regressão polinomial. Verificou-se comportamento quadrático para as variáveis CR, GP, CA, TCE, TDE, CTF, CPF e ALT, obtendo-se os melhores resultados, respectivamente, para GM estimadas em 530,22; 555,40; 597,47; 566,75; 562,07; 557,48; 562,70 e 555,68 µm.(AU)

Corn granulometry in diets for tambaqui juvenile / Granulometria do milho em rações para juvenis de tambaqui

This study aimed to evaluate the performance, carcass composition and viability of different corn granulometry (CG) in diets for tambaqui. It was distributed 160 fish (3.86±0.03g) into 20 aquaria (40-L) in a completely randomized design with five treatments and four replications. The treatments consisted of diets with different CG: 150, 300, 500, 710 and 850 µm. As performance parameters were evaluated: feed intake (FI), weight gain (WG), feed conversion rate (FCR),  final total length (FTL), final standard length (FSL), height (H), specific growth rate (SGR), specific development rate (SDR) and survival (SUR). For carcass composition were evaluated moisture, crude protein, ether extract and mineral matter. For the economic analysis of diet were analyzed the total cost of production (TCP), cost of feed per kg weight gain (CFK) and the index of economic efficiency (IEE). Data were subjected to analysis of variance at 5% probability and polynomial regression. There was quadratic effect for the variables FI, WG, FCR, FTL, FSL, H, SGR and SDR, obtaining the best results, respectively, for CG estimated at 530.22; 555.40; 597.47; 566.75; 562.07; 557.48; 562.70 e 555.68 µm. There was no influence of CG on the carcass composition. There was quadratic effect for TCP and CFK variables, with higher values for CG estimated at, respectively, 600.44 and 602.11 µm.

Objetivou-se avaliar diferentes granulometrias do milho (GM) em rações para juvenis de tambaqui sobre o desempenho zootécnico, composição da carcaça e viabilidade econômica. Foram distribuídos 160 peixes (3,86±0,03 g) em 20 aquários (40 L), em delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Os tratamentos consistiram de rações com diferentes GM: 150, 300, 500, 710 e 850 µm. Como parâmetros de desempenho zootécnico foram avaliados: consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), comprimento total final (CTF), comprimento padrão final (CPF), altura final (ALT), taxa de crescimento específico (TCE), taxa de desenvolvimento específico (TDE) e sobrevivência (SOB). Para composição de carcaça foram avaliados umidade, proteína bruta, extrato etéreo e matéria mineral. Na análise econômica das rações, foram analisados o custo médio com ração por quilograma de peso vivo ganho (CMR), o custo total de produção (CTP) e o índice de eficiência econômica (IEE). Os dados obtidos foram submetidos à análise de variância em nível de 5% de probabilidade e regressão polinomial. Verificou-se comportamento quadrático para as variáveis CR, GP, CA, TCE, TDE, CTF, CPF e ALT, obtendo-se os melhores resultados, respectivamente, para GM estimadas em 530,22; 555,40; 597,47; 566,75; 562,07; 557,48; 562,70 e 555,68 µm.

Densidade de estocagem durante a larvicultura do kinguio / Stocking densities in the larviculture of goldfish

We evaluated the effect of stocking density on the performance of post-larvae goldfish. The experimental units were composed of plastic containers with a volume of one liter. Four hundred and fifteen post-larvae (average length of 4.11 ± 0.93 mm) were distributed in five different stocking densities: 5, 10, 15, 20 and 25 post-larvae L-1. The performance was evaluated after a 24 day period, by weight gain (GP), producing L-¹ (PA), specific growth rate (TCE), development rate specific (TDE) and flock uniformity (U). The survival and parameters of water quality were not affected by the densities studied (P 0.05). It was found a negative effect of increased stocking density in the development of post-larvae and uniformity, indicating that the density of 5 post-larvae L-1 is the most suitable for the larviculture of goldfish.(AU)

Avaliou-se o efeito da densidade de estocagem no desempenho produtivo de pós-larvas de kinguios alimentadas com náuplios de artêmia. As unidades experimentais foram compostas por recipientes plásticos com volume útil de um litro. Foram utilizadas 415 pós-larvas (comprimento médio de 4,11 ± 0,93 mm) distribuídas em cinco densidades de estocagem: 5, 10, 15, 20 e 25 pós-larvas L-1. O desempenho produtivo foi avaliado após 24 dias de cultivo, por meio dos parâmetros de ganho de peso (GP), produção L-1 (PA), taxa de crescimento específico (TCE), taxa de desenvolvimento específico (TDE) e uniformidade do lote (U). A sobrevivência e os parâmetros de qualidade da água não foram afetados pelas densidades estudadas (P 0,05). Verificou-se efeito negativo do aumento da densidade de estocagem no desenvolvimento das pós-larvas e na uniformidade do lote dos animais mantidos nas densidades superiores a 5 pós-larvas L-1, sendo essa indicada para a larvicultura do kinguio.(AU)

Densidade de estocagem durante a larvicultura do kinguio / Stocking densities in the larviculture of goldfish

We evaluated the effect of stocking density on the performance of post-larvae goldfish. The experimental units were composed of plastic containers with a volume of one liter. Four hundred and fifteen post-larvae (average length of 4.11 ± 0.93 mm) were distributed in five different stocking densities: 5, 10, 15, 20 and 25 post-larvae L-1. The performance was evaluated after a 24 day period, by weight gain (GP), producing L-¹ (PA), specific growth rate (TCE), development rate specific (TDE) and flock uniformity (U). The survival and parameters of water quality were not affected by the densities studied (P 0.05). It was found a negative effect of increased stocking density in the development of post-larvae and uniformity, indicating that the density of 5 post-larvae L-1 is the most suitable for the larviculture of goldfish.

Avaliou-se o efeito da densidade de estocagem no desempenho produtivo de pós-larvas de kinguios alimentadas com náuplios de artêmia. As unidades experimentais foram compostas por recipientes plásticos com volume útil de um litro. Foram utilizadas 415 pós-larvas (comprimento médio de 4,11 ± 0,93 mm) distribuídas em cinco densidades de estocagem: 5, 10, 15, 20 e 25 pós-larvas L-1. O desempenho produtivo foi avaliado após 24 dias de cultivo, por meio dos parâmetros de ganho de peso (GP), produção L-1 (PA), taxa de crescimento específico (TCE), taxa de desenvolvimento específico (TDE) e uniformidade do lote (U). A sobrevivência e os parâmetros de qualidade da água não foram afetados pelas densidades estudadas (P 0,05). Verificou-se efeito negativo do aumento da densidade de estocagem no desenvolvimento das pós-larvas e na uniformidade do lote dos animais mantidos nas densidades superiores a 5 pós-larvas L-1, sendo essa indicada para a larvicultura do kinguio.