title: Nutritional and metabolic responses in common dentex (Dentex dentex) fed on different types and levels of carbohydrates.
abstract: The present study was aimed to evaluate the capacity of common dentex (Dentex dentex) to efficiently use dietary carbohydrates. So, the effects of different type and levels of carbohydrates on growth performance, feed utilization, fish composition, plasma metabolites and key metabolic pathways in liver and white muscle of common dentex are presented. Nine isonitrogenous (43%) and isoenergetic (22 MJ kg(-1)) diets were formulated combining three types, pregelatinized starch (PS), dextrin (Dx) and maltodextrin (Mx), and three levels (12, 18 and 24%) of carbohydrates. Growth performance was not significantly influenced by treatments. The best feed utilization was observed in 18% Mx group. Higher hepatic lipid content was found in fish fed lower dietary carbohydrate levels. PS induced higher liver and white muscle hexokinase and pyruvate kinase activities compared to the lower values observed for Mx. Malic enzyme and glucose 6-phosphate dehydrogenase in liver and white muscle were lower in Mx group. The influence of dietary carbohydrates source was more noticeable than those induced by the carbohydrate level, when glycolysis and lipogenesis pathways were considered. Common dentex is able to use properly dietary carbohydrates, although optimal dietary inclusion levels are below 24%. The greater protein-sparing effect was promoted by the less complex carbohydrate (maltodextrin) and the best feed utilization indices were obtained at intermediate levels of inclusion (18%).
authors: Departamento de Zoología, Universidad de Granada, Campus de Fuentenueva, 18071 Granada, Spain; CIMAR/CIIMAR-Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. Electronic address: calaya@ugr.es.
authors: Amalia
authors: A
authors: Pérez-Jiménez
authors: Planta de Cultivos Marinos, Instituto Español de Oceanografía, Mazarrón, 30870 Murcia, Spain.
authors: Emilia
authors: E
authors: Abellán
authors: Planta de Cultivos Marinos, Instituto Español de Oceanografía, Mazarrón, 30870 Murcia, Spain.
authors: Marta
authors: M
authors: Arizcun
authors: Departamento de Zoología, Universidad de Granada, Campus de Fuentenueva, 18071 Granada, Spain.
authors: Gabriel
authors: G
authors: Cardenete
authors: Departamento de Zoología, Universidad de Granada, Campus de Fuentenueva, 18071 Granada, Spain.
authors: Amalia E
authors: AE
authors: Morales
authors: Departamento de Zoología, Universidad de Granada, Campus de Fuentenueva, 18071 Granada, Spain.
authors: M Carmen
authors: MC
authors: Hidalgo
mesh_terms: D000821:Animal Feed; D000818:Animals; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D005399:Fishes / Q000378:metabolism*
chemical_list: D004040:Dietary Carbohydrates
keywords: Common dentex; Dextrin; Intermediary metabolism; Maltodextrin; Plasma metabolites; Pregelatinized starch