Lysine demand and essential aminoacids estimate for tambaqui, Colossoma macropomum (Cuvier, 1818) / Exigência de lisina e estimativa dos aminoácidos essenciais para tambaqui, Colossoma macropomum (CUVIER, 1818)

Four hundred-fifty (450) 7.7±0.06 g juvenile tambaqui were distributed in 500L boxes, fed a casein, gelatin and free amino acids-based semipurified diet containing six lysine levels (L-lysine HCL 0.9; 1.2; 1.5; 1.8; 2,1; 2.4% of the diet), in a completely randomized design, so that their lysine requirements could be determined. Findings demonstrated that diets with rising lysine levels did not influence the assessed zootechnical parameters. Tambaqui presented reduced consumption, low weight gains and high feed conversion with the use of the semipurified diet. This diet affected the hematological parameters significantly with no changes on total proteins and plasmatic glucose. The reduction on the plasmatic cortisol with the increase of lysine in the diet suggests the lower lysine levels to have had an influence on plasmatic cortisol level values. The reduced levels of triglycerides, cholesterol and body lipids with increasing lysine levels suggest a relationship of this amino acid with the accumulation of body lipids. Essencial amino acids demand estimated from tambaqui body amino acids content, showed to be similar to that found for other species and the lysine was estimated at dietary protein 6.0 and 6.2%, through the two utilized methods. The zootechnical performance exhibited by tambaqui, using semipurified diet for the lysine 0.9 to 2.4% interval in the diet did not allow its demand to be determined through dose-response method

Perfis nutricionais e lipídicos dos músculos dorsal e ventral em pirarucus selvagens

The objective of this work was to analyze the proximate and fatty acid composition of the dorsal and ventral muscles of wild pirarucu (Arapaima gigas) captured from a Brazilian Amazonian lake. Dorsal and ventral muscles were dissected out, freeze-dried, vacuum-packed, and had the proximate and fatty acid composition analyzed. Ash, total proteins, and lipids were inversely proportional to moisture and had higher levels in the ventral muscles. Twenty-seven fatty acids were quantified in both muscles without significant differences between them, except for the heneicosylic, palmitoleic, γ-linolenic, and dihomo-γ-linolenic acids. Saturated and monounsaturated fatty acids were predominant in both muscles. The eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were quantitatively similar: 9.25 (dorsal) to 10.14 (ventral) and 8.50 (dorsal) to 10.63 (ventral) mg g-1 of total lipids, respectively. The EPA+DHA content of the dorsal and ventral muscles were 113.25 and 165.78 mg 100 g-1, respectively. The ratios of polyunsaturated/saturated (0.54 and 0.59 for the dorsal and ventral muscles, respectively), n-3/n-6 (0.20 and 0.21), and hypocholesterolemic/ hypercholesterolemic fatty acids (1.41 and 1.45) ratios, as well as the atherogenicity (0.59 and 0.53) and thrombogenicity (1.02 and 0.94) indices, indicate that pirarucu muscle is a good dietary source of EPA+DHA, and its nutritional lipid quality can be beneficial for human health.O objetivo deste trabalho foi avaliar a composição proximal e de ácidos graxos dos músculos dorsal e ventral em pirarucus (Arapaima gigas) selvagens, capturados em um lago amazônico brasileiro. Os músculos dorsal e ventral foram dissecados, liofilizados, embalados a vácuo, e sua composição proximal e de ácidos graxos foram analisadas. Cinzas, proteínas totais e lipídeos foram inversamente proporcionais à umidade e apresentaram teores maiores no músculo ventral. Foram quantificados 27 ácidos graxos em ambos os músculos sem diferença significativa entre eles, exceto para os ácidos heneicosílico, palmitoleico, γ-linolênico e dihomo- γ-linolênico. Ácidos graxos saturados e monoinsaturados predominaram em ambos os músculos. O ácido eicosapentaenoico (EPA) e o docosahexaenoico (DHA) foram quantitativamente similares 9,25 (dorsal) a 10,14 (ventral) e 8,50 (dorsal) a 10,63 (ventral) mg g-1 do total de lipídeos, respectivamente. O conteúdo de EPA+DHA nos músculos dorsal e ventral foi 113,25 e 165,78 mg 100 g-1, respectivamente. A proporção de ácidos graxos poli-insaturados/saturados (0,54 e 0,59 para os músculos dorsal e ventral, respectivamente), n-3/n-6 (0,20 e 0,21) e hipocolesterolêmicos/hipercolesterolêmicos (1,41 e 1,45), assim como os índices de aterogenicidade (0,59 e 0,53) e trombogenicidade (1,02 e 0,94), indicam que o músculo do pirarucu pode ser considerado uma boa fonte dietética de EPA+DHA, e a qualidade nutricional de seus lipídios pode ser benéfica para a saúde humana

Weight-length relationship, condition factor and blood parameters of farmed cichla temensis humboldt, 1821 (Cichlidae) in central Amazon

Farming of native carnivore fish species has drawn attention due to their promising use in aquaculture. Among these species, tucunaré of the genus Cichla stand out, them being of high economical interest for sport fishing and Amazon's industry of ornamental fish. The present study describes the weight-length relationship (WLR), relative condition factor (Kn), red blood cell parameters, thrombocytes and leukocytes count of Cichla temensis Humboldt, 1821, farmed in central Amazon. Fish that underwent food training during fingerling culture received extruded ration containing 45% of crude protein during fattening, and had Kn with values from 0.925-1.199, which indicated good health condition during the culture. The equation obtained from the WLR was W = 0.0073Lt3.1435, indicating an isometric growth, which is the desirable for fish of fish farm. Red blood cell counts, total thrombocyte and leukocyte counts, hematocrit, hemoglobin concentration, mean corpuscular volume (MCV), concentration of mean corpuscular hemoglobin (MCHC), lymphocytes, monocytes and neutrophils had intra-specific variation. A significant (p<0.001) positive correlation of the red blood cells number with the hemoglobin concentration and hematocrit was found. These are the first sets of blood parameters for C. temensis and could be used as reference for comparison in further studies to evaluate the health status of this fish in different environments, because assessment of these parameters may be used as quick tool for diagnosing diseases, stress and malnutrition. © 2011 Sociedade Brasileira de Ictiologia

Dietas para a engorda de pirarucu em tanque rede: Desempenho, parâmetros fisiológicos, composição do filé e custos da alimentação

The present study evaluated practical diets with increasing levels of protein and energy on performance, fillet composition, feed cost, and physiological responses of pirarucu (Arapaima gigas) juveniles during the grow-out phase in a net cage system. In an on-farm trial for 90 days 225 pirarucu juveniles with initial weight ± standard deviation of 2025 ± 335 g were fed to apparent satiety with extruded diets containing 37.4 (T-37), 40.8 (T-40), 43.9 (T-43), 45.5 (T-46), and 47.1% (T-49) crude protein (CP), increasing lipid levels, and energy:protein ratio fixed in 10 kcal g-1. Protein and lipid concentrations in the diets influenced the cost, fillet composition, and important physiological aspects of the health maintenance and productive performance of the pirarucu juveniles. Fish fed the T-37 diet had lower concentrations of fat in body cavity, fillet and blood, and had a lower cost associated with feeding. The increase in protein and energy levels in the other diets tested reduced the economic return, did not improve the zootechnical performance and caused physiological changes in the fish. © 2019, Instytut Technologii Drewna. All rights reserved