80
J. C. Navarro et al.
in aquaculture. Besides, other particular aspects, like the lipid-rich nervous system
of hatchlings of O� vulgaris paralarvae representing approximately one quarter of
the animal’s fresh weight (Packard and Albergoni 1970), suggest the importance
of lipids for suitable growth during planktonic life. Navarro and Villanueva (2000,
2003) made the first approach towards the study of lipid requirements in early stages of cephalopods to conclude that a nutritional imbalance in the lipid and fatty
acid (FA) profile of the artificial feeding protocol may be responsible for the high
mortalities encountered. In particular, O� vulgaris should require feeding on lowlipid preys, rich in polar lipids (PL), long-chain polyunsaturated fatty acids (PUFA)
and possibly cholesterol (Navarro and Villanueva 2000, 2003; Okumura et al. 2005;
Seixas et al. 2008). This closely resembles the composition of a ‘natural’ diet based
on crustacean larvae and other marine planktonic organisms like copepods, but is
far from the typical composition of the enriched Artemia spp. in any of its forms.
The picture is even more complicated after evidences pointing at the paralarvae as
specialist predators, contrary to the general concept by which they had been often
regarded as generalist predators (Roura et al. 2012).
On the other hand, cuttlefish are unable to store lipids in the digestive gland
(Fluckiger et al. 2008) and require high levels of phosphatidylcholine, phosphatidylethanolamine (PE) and cholesterol in their diets (Almansa et al. 2006). This
conclusion was drawn by the latter authors based on data of whole animal (Navarro
and Villanueva 2000), cuttlefish mantle (Sinanoglou and Miniadis-Meimaroglou
1998, 2000) and also of prey lipid content (Domingues et al. 2003; Domingues
et al. 2004). It is, however, interesting to verify that these same lipid classes have
the highest levels throughout cuttlefish wild and culture egg embryonic development and that, although there is a difference in the amount of TL of eggs from
different geographical locations (Sykes et al. 2009a), there is maintenance on the
amount of TL until hatching (Bouchaud and Galois 1990). According to Bouchaud
and Galois (1990), the egg-yolk lipids correspond to 14 % dry weight in eggs and
15 % in hatchlings (mainly phospholipids that may be used for energetic purposes).
However, in the case of octopus, up to now, there is no paralarval food from the
aquaculture artificial food chain that can compare with the lipid composition of natural live food, and every effort has to be made to try to increase the essential longchain PUFA and PL content of live preys. In fact, it is not only the bulk provision
of essential lipids that is important but also the adequate lipid form (Guinot et al.
2013). This scenario may be more important for early stages, and even paramount
in some animal groups like cephalopods, whose FA composition is essentially constituted by palmitic acid (16:0), stearic acid (18:0), docosahexaenoic acid (22:6n-3,
DHA) and eicosapentaenoic acid (20:5n-3, EPA), the latter two being essential longchain highly unsaturated fatty acids (HUFA) for marine organisms (Sinanoglou and
Miniadis-Meimaroglou 1998; Navarro and Villanueva 2000; Passi et al. 2002; Ozyurt et al. 2006; Zlatanos et al. 2006). However, the most recent results from Seixas
et al. (2010) do not completely exclude the importance of DHA for the successful
rearing of O� vulgaris paralarvae but seem to point that maybe other n-3 HUFA
would be more vital. Very interesting results from Quintana (2009) have shown that
EPA is particularly important in paralarvae lipids, with 1:1 EPA:DHA proportions
J. C. Navarro et al.
in aquaculture. Besides, other particular aspects, like the lipid-rich nervous system
of hatchlings of O� vulgaris paralarvae representing approximately one quarter of
the animal’s fresh weight (Packard and Albergoni 1970), suggest the importance
of lipids for suitable growth during planktonic life. Navarro and Villanueva (2000,
2003) made the first approach towards the study of lipid requirements in early stages of cephalopods to conclude that a nutritional imbalance in the lipid and fatty
acid (FA) profile of the artificial feeding protocol may be responsible for the high
mortalities encountered. In particular, O� vulgaris should require feeding on lowlipid preys, rich in polar lipids (PL), long-chain polyunsaturated fatty acids (PUFA)
and possibly cholesterol (Navarro and Villanueva 2000, 2003; Okumura et al. 2005;
Seixas et al. 2008). This closely resembles the composition of a ‘natural’ diet based
on crustacean larvae and other marine planktonic organisms like copepods, but is
far from the typical composition of the enriched Artemia spp. in any of its forms.
The picture is even more complicated after evidences pointing at the paralarvae as
specialist predators, contrary to the general concept by which they had been often
regarded as generalist predators (Roura et al. 2012).
On the other hand, cuttlefish are unable to store lipids in the digestive gland
(Fluckiger et al. 2008) and require high levels of phosphatidylcholine, phosphatidylethanolamine (PE) and cholesterol in their diets (Almansa et al. 2006). This
conclusion was drawn by the latter authors based on data of whole animal (Navarro
and Villanueva 2000), cuttlefish mantle (Sinanoglou and Miniadis-Meimaroglou
1998, 2000) and also of prey lipid content (Domingues et al. 2003; Domingues
et al. 2004). It is, however, interesting to verify that these same lipid classes have
the highest levels throughout cuttlefish wild and culture egg embryonic development and that, although there is a difference in the amount of TL of eggs from
different geographical locations (Sykes et al. 2009a), there is maintenance on the
amount of TL until hatching (Bouchaud and Galois 1990). According to Bouchaud
and Galois (1990), the egg-yolk lipids correspond to 14 % dry weight in eggs and
15 % in hatchlings (mainly phospholipids that may be used for energetic purposes).
However, in the case of octopus, up to now, there is no paralarval food from the
aquaculture artificial food chain that can compare with the lipid composition of natural live food, and every effort has to be made to try to increase the essential longchain PUFA and PL content of live preys. In fact, it is not only the bulk provision
of essential lipids that is important but also the adequate lipid form (Guinot et al.
2013). This scenario may be more important for early stages, and even paramount
in some animal groups like cephalopods, whose FA composition is essentially constituted by palmitic acid (16:0), stearic acid (18:0), docosahexaenoic acid (22:6n-3,
DHA) and eicosapentaenoic acid (20:5n-3, EPA), the latter two being essential longchain highly unsaturated fatty acids (HUFA) for marine organisms (Sinanoglou and
Miniadis-Meimaroglou 1998; Navarro and Villanueva 2000; Passi et al. 2002; Ozyurt et al. 2006; Zlatanos et al. 2006). However, the most recent results from Seixas
et al. (2010) do not completely exclude the importance of DHA for the successful
rearing of O� vulgaris paralarvae but seem to point that maybe other n-3 HUFA
would be more vital. Very interesting results from Quintana (2009) have shown that
EPA is particularly important in paralarvae lipids, with 1:1 EPA:DHA proportions