482
R. Villanueva et al.
particular lipid requirements with relatively high content in phospholipids and
polyunsaturated fatty acids. In consequence, cephalopods can be clustered with the
carnivorous marine finfish species cultured worldwide, which use marine raw materials, such as fishmeal, fish oil and other fishery products for formulated feeds.
Fishmeal includes marine species of high trophic levels on its formulation that are
partially obtained from extractive fisheries, therefore contravening the primary goal
of a sustainable aquaculture, i.e. reducing human pressure on the wild resources and
the environment. Cephalopods are poikilothermic and display many physiological
adaptations that are homologous to vertebrates (Lee 1994). They are fast growers
and mainly composed of protein, with low lipid and carbohydrate content. In addition to protein and lipids, recent studies showed that carbohydrate, mainly metabolised from glycogen, can contribute up to 10 % of the daily energy costs in O�
vulgaris during starvation (Morillo-Velarde et al. 2011), indicating that the role of
carbohydrates as glycogen and its relationship with protein content in artificial diets
should be strengthened in future research.
The future of carnivorous fish and cephalopod farming probably will rely on
feeding them mostly with local discard fish and vegetal raw materials with highquality protein, a goal that has not been yet reached, although considerable research
is being conducted on this aspect for carnivorous fishes (see among others: Ceulemans et al. 2003; Hansen et al. 2007; Benedito-Palos et al. 2008; Díaz-López et al.
2009; Dias et al. 2010; Enes et al. 2010; Pratoomyot et al. 2010). Although, at
present, there are evidences that demonstrate that the vegetable meal produces the
worst amino acid balance for O� vulgaris (Cerezo-Valverde et al. 2013), the use of
those ingredients in diets for cephalopods should be investigated in order to make
a sustainable culture. Multidisciplinary approaches and the ability to integrate a
full range of skills, seldom found in a single group of researchers, may be able
to provide solutions to obtain sustainable artificial feeds for cephalopods. These
feeds need to be visually attractive and have suitable palatability and texture to be
well handled, accepted and ingested, as well as appropriate digestibility to be well
absorbed and metabolised to fit nutritional requirements. This goal will be particularly difficult to achieve for the paralarvae and for juveniles of some species. The
feeding of the early stages of cephalopods has been historically one of the main
bottlenecks in the development of their culture technology. Due to species-specific
biological characteristics, this problem has been partially solved in S� officinalis, S�
lessoniana and O� maya, which have large hatchlings directly called juveniles. For
benthic hatchlings of O� maya, a semi-humid squid paste bound with gelatin has
recently been developed and can be used as the main food, opening a promising
standpoint for other species (Rosas et al. 2008, 2013). In S� officinalis, hatchlings
were early fed on frozen food leading to the perspective of acceptance of a prepared
food from the first day (Sykes et al. 2013). The well-developed nervous system,
responsible for the sensory world of cephalopods and their learning capabilities,
may be a valuable tool in training these animals to feed on suitable artificial feeds.
Recent studies have shown the ability for embryonic learning in the cuttlefish S�
officinalis (Darmaillacq et al. 2008), a characteristic that may be used in the future
for the juvenile rearing by conditioning hatchling prey preferences, an unexplored
R. Villanueva et al.
particular lipid requirements with relatively high content in phospholipids and
polyunsaturated fatty acids. In consequence, cephalopods can be clustered with the
carnivorous marine finfish species cultured worldwide, which use marine raw materials, such as fishmeal, fish oil and other fishery products for formulated feeds.
Fishmeal includes marine species of high trophic levels on its formulation that are
partially obtained from extractive fisheries, therefore contravening the primary goal
of a sustainable aquaculture, i.e. reducing human pressure on the wild resources and
the environment. Cephalopods are poikilothermic and display many physiological
adaptations that are homologous to vertebrates (Lee 1994). They are fast growers
and mainly composed of protein, with low lipid and carbohydrate content. In addition to protein and lipids, recent studies showed that carbohydrate, mainly metabolised from glycogen, can contribute up to 10 % of the daily energy costs in O�
vulgaris during starvation (Morillo-Velarde et al. 2011), indicating that the role of
carbohydrates as glycogen and its relationship with protein content in artificial diets
should be strengthened in future research.
The future of carnivorous fish and cephalopod farming probably will rely on
feeding them mostly with local discard fish and vegetal raw materials with highquality protein, a goal that has not been yet reached, although considerable research
is being conducted on this aspect for carnivorous fishes (see among others: Ceulemans et al. 2003; Hansen et al. 2007; Benedito-Palos et al. 2008; Díaz-López et al.
2009; Dias et al. 2010; Enes et al. 2010; Pratoomyot et al. 2010). Although, at
present, there are evidences that demonstrate that the vegetable meal produces the
worst amino acid balance for O� vulgaris (Cerezo-Valverde et al. 2013), the use of
those ingredients in diets for cephalopods should be investigated in order to make
a sustainable culture. Multidisciplinary approaches and the ability to integrate a
full range of skills, seldom found in a single group of researchers, may be able
to provide solutions to obtain sustainable artificial feeds for cephalopods. These
feeds need to be visually attractive and have suitable palatability and texture to be
well handled, accepted and ingested, as well as appropriate digestibility to be well
absorbed and metabolised to fit nutritional requirements. This goal will be particularly difficult to achieve for the paralarvae and for juveniles of some species. The
feeding of the early stages of cephalopods has been historically one of the main
bottlenecks in the development of their culture technology. Due to species-specific
biological characteristics, this problem has been partially solved in S� officinalis, S�
lessoniana and O� maya, which have large hatchlings directly called juveniles. For
benthic hatchlings of O� maya, a semi-humid squid paste bound with gelatin has
recently been developed and can be used as the main food, opening a promising
standpoint for other species (Rosas et al. 2008, 2013). In S� officinalis, hatchlings
were early fed on frozen food leading to the perspective of acceptance of a prepared
food from the first day (Sykes et al. 2013). The well-developed nervous system,
responsible for the sensory world of cephalopods and their learning capabilities,
may be a valuable tool in training these animals to feed on suitable artificial feeds.
Recent studies have shown the ability for embryonic learning in the cuttlefish S�
officinalis (Darmaillacq et al. 2008), a characteristic that may be used in the future
for the juvenile rearing by conditioning hatchling prey preferences, an unexplored