RESUMO O presente estudo teve como objetivo avaliar a influência do óleo essencial de alho (OEA) sobre o desempenho produtivo e as variáveis morfométricas de pós-larvas de acará severo (Heros severus). Foi realizado ensaio de crescimento com 150 pós-larvas severas (1,6 ± 0,03 mg e 5,58 ± 0,1 mm), distribuídas em quinze aquários de 1 L, com aeração constante. Os peixes foram distribuídos em delineamento inteiramente casualizado com cinco tratamentos, dietas contendo diferentes níveis de OEA (0,00; 0,05; 0,50; 1,00 e 1,50 g kg-1) e três repetições. As dietas foram oferecidas quatro vezes ao dia, até saciedade aparente, por 30 dias. Ao final do experimento, os peixes foram contados, pesados e medidos, para avaliação do desempenho produtivo e das variáveis morfométricas. O aumento dos níveis de OEA na dieta resultou em redução linear nos parâmetros de desempenho produtivo, com exceção da taxa de sobrevivência e uniformidade de peso e comprimento do lote, que não apresentaram diferenças significativas, assim como as variáveis morfométricas. Concentrações elevadas de OEA na dieta podem ser prejudiciais para larvas e pós-larvas de peixes, que podem ser mais sensíveis ao dano potencial que altas concentrações deste óleo essencial podem causar. Portanto, a inclusão de OEA em níveis acima de 0,05 g kg-1 em dietas para pós-larvas de acará severo não é recomendada.

ABSTRACT The present study aimed to evaluate the influence of garlic essential oil (GEO) on the growth performance and morphometric variables of severum (Heros severus) post-larvae. A growth trial was performed using 150 severum post-larvae (1.6 ± 0.03 mg and 5.58 ± 0.1 mm), distributed in fifteen 1-L aquaria, with constant aeration. The fish were essayed in a completely randomized design with five treatments, using diets containing graded levels of GEO (0.00, 0.05, 0.50, 1.00 and 1.50 g kg-1) and three replicates. The diets were offered four times a day, until apparent satiation, for 30 days. At the end of the experiment, the fish were counted, weighed and measured, to evaluate growth performance and morphometric variables. Increased diet levels of GEO resulted in a linear reduction in growth performance parameters, except for the survival rate, weight and length uniformity of the batch, and morphometric variables which did not present significant differences. Elevated concentrations of dietary GEO may be detrimental to larvae and post-larvae of fish, which could be more sensitive to the potential damage that high concentrations of this essential oil may cause. Therefore, the inclusion of GEO in levels above 0.05 g kg-1 in diets for severum post-larvae is not recommended.

ABSTRACT The influence of feeding frequency on growth performance, batch uniformity, and survival rate of severum (Heros severus) larvae and juveniles was investigated in two experiments. In the first, 200 five-day-old severum larvae with 3.20±0.31 mg and 6.20±0.39 mm were randomly distributed into 20 aquaria (1 L) and fed 500 Artemia nauplii larvae−1 day−1 for 15 days. In the second, 120 severum juveniles, 178.19±33.59 mg and 1.82±0.09 cm, were randomly distributed into 15 aquaria (300 L) and hand-fed a commercial diet (400.0 g kg−1 crude protein and 21.2 kJ g−1 gross energy) until apparent satiety for 30 days. For both experiments, feeding frequencies of one, two, three, four, and five meals day−1 were evaluated. We used four replicates for the first experiment and three for the second. At the end of both experiments, survival rate and batch uniformity were unaffected by the feeding frequency. Severum larvae fed three, four, and five meals day−1 showed higher final weight, weight gain, and specific growth rate, but only the larvae fed five meals day−1 showed higher final length and length gain than those fed once and twice day−1. Severum juveniles fed two, four, and five meals day−1 showed higher final weight, weight gain, and specific growth rate. Growth performance parameters of final length and length gain were not affected by feeding frequencies. Thus, we recommend that the optimal feeding frequency for severum larvae fed Artemia nauplii is three meals day−1 and for juvenile severum fed a commercial diet, the optimal frequency is two meals day−1.

ABSTRACT A 90-day feeding trial was conducted to estimate the dietary lysine requirement of adult lambari ( Astyanax altiparanae ), based on growth performance, whole-body composition, muscle development, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. Six isoproteic (345.0 g kg−1) and isoenergetic (19.51 MJ kg−1) diets were formulated, and crystalline L-lysine was added to obtain diets with lysine concentrations of 12.13, 13.31, 15.36, 18.79, 19.92, and 23.02 g kg−1 dry diet. Female adult lambari (n = 480; weight of 4.96±0.02 g) were distributed into 24 (70 L) aquaria and fed the experimental diets six times daily. Fish fed 12.13 to 19.92 g kg−1 lysine showed increased weight gain and percent weight gain, and fish from those treatments also showed improvement in final carcass quality by a decrease in whole-body lipid content. Fish fed 12.13 g kg−1 lysine showed lower ALT and AST activities in blood serum when compared with fish fed the highest lysine levels. No differences were observed in muscle growth in fish fed graded lysine levels. According to the broken-line model analysis of weight gain and dietary lysine levels, the dietary lysine requirement of adult lambari is estimated at 18.72 g kg−1 (5.41% of dietary protein).

Resumo O objetivo deste trabalho foi desenvolver massas de pizza com diferentes níveis de inclusão de farinha de atum (Tunnus spp.). Para a produção da farinha de atum, foram utilizados troncos de atum sem nadadeiras, cozidos por uma hora, prensados, moídos e desidratados por 24 horas a 60 °C. Foram elaboradas massas de pizza sem inclusão (0%) ou com inclusão de 5, 10, 15 e 20% de farinha de atum, sendo estas inclusões calculadas com base na quantidade de farinha de trigo. A farinha de atum e as diferentes massas foram analisadas quanto aos teores de umidade, proteína bruta, lipídeos totais, cinzas e carboidratos, além do valor calórico e do perfil de ácidos graxos. Análises microbiológica e sensorial foram realizadas nas massas de pizza. A crescente inclusão de farinha de atum resultou em aumento do teor de proteína bruta (10,89 a 18,94%), de lipídeos totais (4,63 a 5,89%) e de cinzas (2,54 a 3,54%) nas massas, sem influenciar no teor de umidade e no valor calórico. A inclusão de farinha de atum aumentou linearmente a quantidade de ácidos graxos da série n-3 nas massas, com aumento de 1,56 para 5,93 g/kg, em 20% de inclusão de farinha de atum. A relação entre ácidos graxos poli-insaturados e saturados da farinha de atum e das massas variou entre 1,21 e 1,85. A análise microbiológica demonstrou que as massas foram produzidas em condições adequadas de higiene. Observou-se que a inclusão de 5 a 20% de farinha de atum na massa de pizza não interferiu significativamente (p>0,05) nos parâmetros de aroma, sabor, impressão global e intenção de compra. Concluiu-se que a inclusão de 5 até 20% de farinha de atum é eficaz para melhorar o valor nutritivo e o perfil de ácidos graxos de massa de pizza.

Abstract The aim of this study was to develop pizza dough with different levels of tuna meal (Tunnus spp.). In order to produce tuna meal, tuna torsos without fins were used, cooked for 1 hour, pressed, milled and dehydrated for 24 hours at 60 °C. Pizza dough was produced without (0%) or with the addition of 5, 10, 15 and 20% of tuna meal, calculated based on the quantity of wheat flour. The tuna meal and different pizza pastries were analyzed for moisture content, crude protein, total lipids, ash, carbohydrates, caloric value and fatty acid profiles. Microbiological and sensory analyses were also carried out on the pizza pastries. The increasing addition of tuna meal resulted in gains in the crude protein (10.89 to 18.94%), total lipid (4.63 to 5.89%) and ash (2.54 to 3.54%) contents of the pizza pastries, not influencing the moisture content or caloric value. The inclusion of tuna meal linearly increased the quantity of n-3 series fatty acids in the pizza pastry, from 1.56 to 5.93 g/kg with the addition of 20% tuna meal. The ratio between the polyunsaturated and saturated fatty acids in the tuna meal and pizza pastries varied from 1.21 to 1.85. The microbiological analyses showed that the pizza pastries were produced under proper hygiene conditions. It was also observed that the addition of 5 to 20% of tuna meal to the pizza pastry did not significantly (p>0.05) alter the parameters of aroma, flavor, overall impression and purchase intention. It was therefore concluded that the addition of 5 to 20% tuna meal is effective in improving the nutritional value and fatty acid profile of pizza pastry.

Abstract Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal) and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07%) and salmon (72.40%). A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.

The objective of this study was to investigate the effect of different water salinities on juvenile Hoplias lacerdae during feed training. Salinity levels of 0, 3, 6 and 9 g salt L-1 were used. Juveniles (3.33±0.1 cm and 0.6±0.09 g) were stocked at a density of six fish L-1 in aquaria (10 L volume) with supplementary aeration. Weight gain, length gain, and rates of survival, mortality, and cannibalism were evaluated after 20 days. Total mortality was observed in 0 g of salt L-1. The best survival rates of 98.7 and 97.5% were recorded in 3 and 6 g of salt L-1, respectively. The greatest weight gain was recorded in fish grown in 3 g of salt L-1 followed by fish grown in 6 g of salt L-1. Length gain was similar in the 3 and 6 g salt L-1 groups. No weight or length gain was recorded in 9 g of salt L-1. According to regression equations, the optimum water salinity was 5.15, 4.03 and 4.55 g of salt L-1 for survival rate, weight, and length gain, respectively. Salinity between 4.03 and 5.15 g of salt L-1 during feed training of juvenile giant trahira improves productive performance.

The aim of this study was to evaluate the influence of light intensity on the feed training of juvenile giant trahiras (Hoplias lacerdae). A completely randomized design with four light treatments and three replicates was used, and the following light intensities were tested: 204.9; 177.58; 54.64 and 0.00 lux. Juvenile giant trahiras (length = 3.0 ± 0.4 cm and weight = 0.5 ± 0.05 g) were stocked at 6 fish L-1 in 12 rectangular tanks (24 × 20 × 14 cm) containing six liters of water, and subjected to feed training to accept dry diets. At the end of the experiment (21 days), weight gain, length gain, survival, cannibalism, and mortality rates were evaluated. Data were subjected to regression analysis at 5% probability. Different light intensities did not affect growth, survival, mortality, or cannibalism rates in juvenile giant trahiras during the feed training. Therefore, this species can be trained to accept dry diets in the presence or absence of light.

Com este trabalho objetivou-se avaliar a suplementação de vitamina C durante a fase de condicionamento alimentar de alevinos de trairão. Um experimento foi estabelecido em delineamento inteiramente casualizado com sete tratamentos (0,0; 17,5; 52,5; 87,5; 122,5; 175,0 e 350,0 mg de vitamina C/kg de ração) e quatro repetições. Alevinos de trairão (2,8 ± 0,2 cm) foram distribuídos em aquários de 6 L, na densidade de 6 peixes/L. Uma ração basal foi confeccionada com 44,0% proteína bruta, e diariamente foi adicionada vitamina C e coração bovino. Após 20 dias, realizou-se biometria dos peixes para avaliação do ganho de peso e do comprimento, das taxas de sobrevivência e canibalismo e da uniformidade do comprimento final e para observações macroscópicas de sinais clínicos de deficiência ou excesso da vitamina. Após a biometria, dez peixes de cada dieta testada foram coletados para análise do perfil de ácidos graxos e este perfil foi comparado ao perfil de peixes, na mesma fase de vida, alimentados com peixes forrageiros coletados de viveiros de criação. Os dados de desempenho produtivo e perfil de ácidos graxos foram submetidos a análise de regressão polinomial e a uniformidade do comprimento final avaliada pelo teste de Bartlett. Houve diferença significativa apenas para a uniformidade em comprimento final e perfil de ácidos graxos da carcaça. A suplementação com 52,5 mg de vitamina C/kg de ração proporcionou maior uniformidade do comprimento final dos peixes. Os peixes dos viveiros de criação apresentaram menor concentração de PUFA (polyunsaturated fatty acids) e maior de ácidos graxos saturados em comparação aos peixes condicionados a aceitar dietas secas.

The objective of this work was to evaluate suplemenation of vitamin C during feed training of giant trahira fingerlings. An experiment was established in a complete random design with seven treatments (0.0, 17.5, 52.5, 87.5, 122.5, 175.0 and 350.0 mg vitamin C/kg diet) and four repetitions. Giant trahira fingerlings (2.8 ± 0.2 cm) were distributed in 6-L aquaria at the density of 6 fish/L. A basal diet was formulated with 44.0% of crude protein and vitamin C and bovine heart were added in it daily. After 20 days, biometry of fish for evaluation of weight and length gains, rates of survival and cannibalism and uniformity of final length and for macroscopic observations of clinical signs of deficiency or excess of vitamin was carried out. After biometry evaluation, ten fish from each tested diet were collected for analysis of the fatty acid profile which was compared to profile of fish at the same life stage fed forage fish collected from breeding fishponds. Data on growth performance and fatty acid profiles were submitted to analyses of polynomial regression and uniformity of the final length was evaluated by the Bartlett test. There was a significant difference only for uniformity in final length and fatty acid profile of the carcass. Supplementation with 52.5 mg vitamin C/kg diet provided a greater uniformity of the final length of the fish. Fish from breeding fishponds presented lower concentration of PUFA (polyunsaturated fatty acids) and higher concentration of saturated fatty acids compared to fish trained to accept dry diets.