Parâmetros metabólicos de pacus alimentados com diferentes fontes de óleo

Abstract

Resumo -O objetivo deste trabalho foi avaliar parâmetros metabólicos de pacus (Piaractus mesopotamicus) alimentados com dietas com diferentes óleos. O experimento foi conduzido em laboratório, em maio de 2009, durante 28 dias. Foram utilizados 64 pacus com peso inicial de 61 g, mantidos em tanques de 250 L. Os tratamentos foram: dieta controle mais óleo de oliva; dieta controle mais óleo de milho; dieta controle mais óleo de peixe; e dieta controle mais óleo de milho e de peixe. Utilizou-se o delineamento inteiramente casualizado, com quatro repetições, em arranjo fatorial 4x4 (quatro dietas e quatro tempos de coleta: 7, 14, 21 e 28 dias). Foram avaliados: níveis sanguíneos de colesterol e lipoproteínas, composição química muscular, e atividade de glicose-6-fosfato desidrogenase (G6PD) e enzima málica (EM). Os dados foram submetidos à análise de variância, à comparação das médias pelo teste de Tukey, e à análise de regressão. Não houve diferença nos teores musculares de umidade e cinzas, mas foram observadas alterações na deposição lipídica e proteica, conforme os tempos de coleta, em todos os tratamentos. As dietas interferiram nos parâmetros sanguíneos avaliados. A atividade de G6PD é superior à da EM, sendo maior nos animais alimentados com óleo de oliva e milho, o que sugere maior deposição lipídica muscular nestes peixes. Portanto, o metabolismo lipídico do pacu é influenciado pela composição do lipídio da dieta.Termos para indexação: Piaractus mesopotamicus, ácido graxo, enzimas, nutrição, peixe. Metabolic parameters of pacu fed different oil sourcesAbstract -The objective of this work was to evaluate the metabolic parameters of pacu (Piaractus mesopotamicus) fed diets with different oils. The experiment was conducted in the laboratory, on May 2009, during 28 days. Sixty four fish with initial weight of 61 g, kept in 250 L tanks, were used. The treatments were: control diet plus olive oil; control diet plus corn oil; control diet plus fish oil; and control diet plus corn oil and fish oil. A completely randomized design was used, with four replicates and a 4x4 factorial arrangement (four diets and four sampling times: 7, 14, 21, and 28 days). The following were evaluated: cholesterol and lipoprotein blood levels, muscle chemical composition, and activity of glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME). The data were subjected to analysis of variance, comparisons of means using the Tukey test, and to regression analysis. There were no differences in muscle levels of moisture or ash, but changes were observed in lipid and protein deposition, depending on collection time, for all treatments. The diets interfered in the evaluated blood parameters. G6PD activity is higher than that of ME, being higher in animals fed with olive and corn oil, suggesting more lipid deposition in the muscles of these fish. Therefore, the lipid metabolism of pacu is influenced by the lipid composition of the diet.

Effect of corn in diets for carnivorous catfish (Lophiosilurus alexandri) on metabolic and performance parameters

“…Malic enzyme and G6PD are lipogenic enzymes involved in catalysing NADPH production, which is essential for fatty acid biosynthesis (Enes et al, 2009;Lin & Shiau, 1995;Lu et al, 2018). The activity of these enzymes may indicate the nutritional status of fish (Metón, Fernández, & Baanante, 2003;Ribeiro, Costa, Pereira, Murgas, & Rosa, 2013). The stimulus generated by carbohydrate-rich diets with regard to G6PD activity has also been reported for rainbow trout (Oncorhynchus mykiss) and sole (Solea senegalensis.…”

Feeding behaviour, locomotion rhythms and blood biochemistry of the neotropical red‐tail catfish (Phractocephalus hemioliopterus)

“…Lipoproteins act in the transport of lipids (Champe et al ., 2009; Ribeiro et al ., 2013). LDL has the function of transporting cholesterol from the liver to peripheral tissues, while HDL acts to transport cholesterol from peripheral tissues to the liver (Champe et al ., 2009; Chen et al ., 2003).…”