Paralarvae rearing

At hatching, O. vulgaris paralarvae (defined by Young and Harman, 1988) show a total length of 3 mm and an individual dry weight of 0.20-0.35 mg (Iglesias, personal communication Fig. 12.2). 

The main problem impeding commercial culture lies in the high mortality rate observed in the paralarval rearing during the first two months of life. Despite the limited knowledge on the fundamental biological and physical requirements of cephalopod paralarvae and their behaviour, many attempts have been made to explore the feasibility of their culture. 

For many years, there have been discussions about what causes the high larval mortality observed during the first two months of life. Two possible factors have been considered as responsible of this mortality (Iglesias et al, 2007a) the lack of a standardised culture system and the absence of a suitable live food source to cover the paralarvae requirements. The following recommendations about paralarvae rearing parameters are made based upon 15 years of research and practical experience. 

With respect to food supply, it is generally accepted that Artemia constitutes an attractive prey that is well accepted by octopus larvae. However, there are discrepancies concerning the optimal size of the Artemia to be supplied to the culture tanks. Some authors (Navarro and Villanueva, 2003) use Artemia nauplii of 450-750 pm, in the first few weeks of culture, while others (Moxica et al, 2002 Iglesias et al, 2004 Carrasco et al, 2005 Estevez et al, 2009) use Artemia bigger than 2 mm in length which are better accepted than the nauplii at first feeding (Iglesias et al, 2006). 

Parameters Barcelona ICM-CSIC Vigo lEO Canary Islands ICCM Asturias CEP Andalusia IFAPA 

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Key words cephalopoda. Octopus vulgaris, culture, reproduction, paralarvae rearing. 

Table 12.2 Summary of paralarvae rearing conditions of Octopus vulgaris carried out by different research groups...

Fig. 12.7 Diagram of Octopus vulgaris paralarvae rearing tank.

Table 12.3 Participants in the Working Group on paralarvae rearing of Octopus vulgaris. Vigo (Spain), 7-11 November 2005...

NAVARRO J c and VILLANUEVA R (2003) The fatty acid composition of Octopus vulgaris paralarvae reared with live and inert food deviation from their natural fatty acid proftlC, Aquaculture, 219, 613-631. 

SEIXAS p, REY-MfiNDEZ M, VALENTE L M P and OTERO A (2010) High DHA content in Anemia is ineffective to improve Octopus vulgaris paralarvae rearing . Aquaculture, 300,156-162. 

VICIANO E, IGLESIAS J, LAGO M J, sAnCHEZ F J, OTERO J J and NAVARRO J C (2011) Fatty acid composition of polar and neutral lipid fractions of Octopus vulgaris Cuvier, 1797 paralarvae reared with enriched on-grown Artemia , Aquae Res, 42, 704-709. 

Nutrition It is necessary to continue research into the nutritional requirements of paralarvae (lipids, proteins, aminoacids, essential elements and vitamins) both in wild and culture conditions to solve the problem of larval rearing. 

VILLANUEVA R (1994) Decapod crab zoeae as food for rearing cephalopod paralarvae , Aquaculture, 128,143-152. 

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