Growth performance and metabolic utilization of diets with different proteimcarbohydrate ratios by white sea bream (Diplodus sargus, L.) juveniles

摘要

Carbohydrates are the most economical dietary energy sources. Therefore, utilization of carbohydrates by fish has been the subject of different studies aiming to evaluate their potential of incorporation into fish diets, aiming to minimize fish production costs (Wilson 1994). Although fish do not use carbohydrate as efficiently as mammals and birds, its nutritional value depends on fish species. However, metabolic differences in carbohydrate utilization among species are still poorly known. These maybe due to differences in enzyme activity or expression, hormonal secretion or number of receptors in target cells (Wilson 1994; Hemre, Mommsen & Kroghdahl 2002). Furthermore, differences in carbohydrate digestion capability also exist, with omnivorous species presenting higher amylolitic activity than carnivorous species (Wilson 1994; Stone 2003; Krogdahl, Hemre & Mommsen 2005).