Browsing by Author "Rodríguez, Covadonga"
Now showing 1 - 5 of 5
Results Per Page
Sort Options
- Characterization of deformed hatchlings of Octopus vulgaris obtained under captivity from a small femalePublication . Jiménez-Prada, Pablo; Scherbakova, Anastasia; Riera, Rodrigo; Felipe, Beatriz C.; Sykes, António V.; Gonçalves, Rui A.; Andrade, José Pedro; Perales-Raya, Catalina; Rodríguez, Covadonga; Almansa, EduardoThe common octopus (Octopus vulgaris), a promising species for aquaculture, spawns easily under cap-tivity from mature females (usually above 1 kg wet weight). Octopus juveniles and adults are collectedfrom nature to obtain eggs and paralarvae for aquaculture development trials. In July 2011, a very smallfemale (150 g wet weight but with an age estimation of 300 days-old) spawned almost 77,000 paralar-vae. Malformations of paralarvae were noticed in the first spawning days, namely the absence of arms.Despite not being lethal, these abnormalities might be derived from the physiological condition of thebreeding specimen (the female’s lower weight to the estimated amount of living days), which might beeventually related to nutritional unbalances or genetic parameters that were transferred to the eggs.
- Comparative study on fatty acid metabolism of early stages of two crustacean species: Artemia sp. metanauplii and Grapsus adscensionis zoeae, as live prey for marine animalsPublication . Reis, Diana; Acosta, Nieves G.; Almansa, Eduardo; Navarro, Juan C.; Tocher, Douglas R.; Andrade, José Pedro; Sykes, António V.; Rodríguez, CovadongaThe present study compared the lipid composition and in vivo capability of Artemia sp. metanauplii (the main live prey used in aquaculture) and Grapsus adscensionis zoeae (as a wild zooplankton model) to metabolise unsaturated fatty acids. The two species were incubated in vivo with 0.3μM of individual [1-14C]fatty acids (FA) including 18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6 (ARA), 20:5n-3 (EPA) and 22:6n-3 (DHA) bound to bovine serum albumin (BSA). Compared to metanauplii, zoeae contained twice the content of polar lipids (PL) and eight-fold the content of long-chain polyunsaturated fatty acids (LC-PUFA). Artemia sp. metanauplii showed increased short chain fatty acid de novo synthesis from beta-oxidation of [1-14C]LC-PUFA, preferentially DHA. Of the LC-PUFA, DHA showed the highest esterification rate into Artemia sp. triacylglycerols. In contrast, in Grapsus zoeae [1-14C]DHA displayed the highest transformation rate into longer chain-length FAs and was preferentially esterified into PL. EPA and ARA, tended to be more easily incorporated and/or retained than DHA in Artemia sp. Moreover, both EPA and ARA were preferentially esterified into Artemia PL, which theoretically would favour their bioavailability to the larvae. In addition to the inherent better nutritional value of Grapsus zoeae due to their intrinsic lipid composition, the changes taking place after the lipid incorporation, point at two distinct models of lipid metabolism that indicate zoeae as a more suitable prey than Artemia sp. for the feeding of marine animals.
- Effects of increased tank bottom areas on cuttlefish (Sepia officinalis, L.) reproduction performancePublication . Sykes, António V.; Pereira, Diana; Rodríguez, Covadonga; Lorenzo, António; Andrade, José PedroMuch interest on cuttlefish research during the last years has focused on its introduction as a new species for aquaculture. This is due to this species biological (Barnabe´ 1996) and economical (FAO 2009) aspects which display potential for industrial culture. Recently, Sykes, Domingues, Correia and Andrade (2006) reviewed this potential, the state of the art and future trends of research for the European cuttlefish, Sepia officinalis. In this work, a series of bottlenecks were identified that need to be resolved before the technology acquires sufficient maturity to enable a transition to the industrial scale. Control of reproduction in captivity is essential for the sustainability of commercial aquaculture production. This factor was identified as a major bottleneck in cuttlefish culture due to several biological aspects of the species, such as semelparity, low fecundity and fertility and eventually inbreeding (Sykes, Domingues & Andrade 2006).
- Meta-analysis approach to the effects of live prey on the growth of octopus vulgaris paralarvae under culture conditionsPublication . Garrido, Diego; Martín, Virginia M.; Rodríguez, Covadonga; Iglesias, José; Navarro, Juan C.; Reis, Diana; Riera, Rodrigo; Sykes, António V.; Almansa, EduardoThe common octopus (Octopus vulgaris, Cuvier 1797) is a species with increasing interest for marine aquaculture diversification, given its high growth rate and easy adaptation to captivity, among other positive features (Iglesias et al. 2007, 2014a). However, the massive paralarvae mortalities verified under culture conditions ( 100% in most studies) have hampered its commercial production, therefore making this the main bottleneck for industrial farming. According to several authors (Iglesias et al. 2007, 2014a; Iglesias & Fuentes 2013), the high mortalities could be due to: (i) inadequate and/or unbalanced diets that do not fulfil paralarvae nutritional requirements, (ii) lack of standardized rearing techniques, and (iii) little knowledge about octopus paralarvae physiology and behaviour.
- Preliminary results on light conditions manipulation in Octopus vulgaris (Cuvier, 1797) paralarval rearingPublication . Garrido, Diego; Reis, Diana; Orol, Diego; Gonçalves, Rui A.; Martín, M.; Sykes, António V.; Rodríguez, Covadonga; Felipe, Beatriz; Zheng, Xiaodong; Lagos, Luis; Almansa, EduardoHigh paralarvae mortality is a major bottleneck currently hindering the control over the lifecycle of common octopus (Octopus vulgaris Cuvier, 1797). It is believed that this problem might be related to either zoo-technical and/or nutritional aspects. The present paper is focused on the study of different zoo-technical aspects related to light conditions on the rearing of paralarvae, including the effects of polarization in prey ingestion, the use of a blue filter to simulate natural conditions, and the use of focused light to avoid reflections of the rearing tank’s walls. In the first experiment, O. vulgaris paralarvae ingestion of Artemia sp. and copepods (Tisbe sp.) was assessed under either normal or polarized light. In the second experiment, the effect of a blue filter with natural light or focused artificial light on growth and mortality was assessed over 15 days of rearing. Ingestion rate was not influenced by light polarization. Nonetheless, a significantly higher ingestion of Artemia sp. with respect to copepods was observed. The blue filter promoted the use of natural light conditions in Octopus paralarval culture, while focused light reduced the collision of the paralarvae against the walls. However, no significant differences were found in paralarval growth nor survival.