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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 (Wilson1994). 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 may be 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). White sea bream (Diplodus sargus, L.) is a Mediterranean sparid with potential for aquaculture diversification or for free-ranging purposes. Its production technology is similar to that of gilthead sea bream, its market value is high and larval and fingerling growth is similar or even higher than that of sea bream (Cejas, Samper, Jerez, Fores & Villamandos 1993; AbellaŁn & Garcia-AlcazaŁr 1995). It does, however, seem to become a slow grower in later stages (Cejas et al. 1993; Divanach, Kentouri, Charalambakis, Pouget & Sterioti 1993; AbellaŁn & Garc|¤ a-AlcazaŁr 1995). Nonetheless, this may possibly be improved by genetic selection or the use of more adequate diets. Indeed, nutritional requirements of white sea bream are still poorly known, and fish are usually fed …