Browsing by Author "Rodriguez, C."
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- A general survey of the feasibility of culturing the mysid Gastrosaccus roscoffensis (Peracarida, Mysida): growth, survival, predatory skills, and lipid compositionPublication . Escanez, A.; Riere, R.; Marquez, L.; Skalli, A.; Felipe, B. C.; Garcia-Herrero, I.; Reis, D.; Rodriguez, C.; Almansa, E.The effects of culture conditions on growth, survival, predation, and nutritional composition of the mysid Gastrosaccus roscoffensis were studied. Light had a negative effect on the predation rates of G roscoffensis and predator size was important to prey on Artemia nauplii and rotifers (Brachionus plicatilis). Growth rates were higher in the first three weeks and measured individuals increased almost 7 mm in length in six weeks. Mortality rate was not constant, but it peaked during the first 10 days and after the 40th day of culture. Lipid class composition of cultured G. roscoffensis juveniles showed differences compared to wild G roscoffensis and other mysid species, with a high proportion of neutral lipids (72.04% total lipids) mainly triacylglycerol (41.74%). Fatty acid composition was characterized by high levels of 18:3n-3 (23.16% total lipids) and monoenes in cultured G. roscoffensis. The experiments demonstrated the feasibility of the culturing conditions assayed for G roscoffensis, although further experiments should be carried out to test this mysid as a prey for new species of commercial interest, including fish and cephalopods.
- In vivo metabolism of unsaturated fatty acids in Sepia officinalis hatchlingsPublication . Reis, Diana; Rodriguez, C.; Acosta, N. G.; Almansa, E.; Tocher, D. R.; Andrade, José Pedro; Sykes, António V.The transition of Sepia officinalis culture to industrial large scale has been hampered due to bottlenecks related to the limited knowledge on nutritional physiology of the species. Determination of the endogenous ability of S. officinalis hatchlings to metabolise unsaturated fatty acids (FA) may provide new insight on the capability of hatchlings to biosynthesise different FA, as well as lipid classes containing essential fatty acids (EFA). In the present study, cuttlefish hatchlings were incubated with [1-C-14] FA including C18 FA (18:1n-9, 18:2n-6, 18:3n-3) and long-chain polyunsaturated fatty acids (LC-PUFA) (20: 4n-6 (ARA), 20:5n-3 (EPA) or 22:6n-3 (DHA)), which were added individually as potassium salts bound to bovine serumalbumin. As a result, it was possible to investigate the in vivo FAmetabolismof S. officinalis hatchlings by following the incorporation of specific [1-C-14] FA, which points to the suitability of this methodology to study lipid metabolism of newly hatched cephalopods. The majority of radioactivity incorporated was recovered esterified into polar lipids (PL). A pattern was detected, where [1-C-14] DHA, [1-C-14] C18 FA and their metabolic products were preferentially esterified into phosphatidylcholine, whereas [1-C-14] ARA and [1-C-14] EPA were mainly esterified into phosphatidylethanolamine. [1-C-14] C18 FA were the most transformed FA with several metabolites produced by elongation and possible desaturation being obtained. As a contrary the radioactivity incorporated into hatchling total lipid (TL) from supplemented [1-C-14] LC-PUFA only one elongation product was recovered from the three substrates, except for [1-C-14] ARA, where an unidentified product was also detected. The present in vivo results indicated that S. officinalis hatchlings may have capability for the first steps in the biosynthesis of ARA and EPA from 18: 2n-6 and 18: 3n-3, respectively, including the existence of a desaturase potentially involved. Nonetheless, considering the low desaturation rates detected, this process may not be sufficient to cover EFA demands during development of this species. Therefore, dietary ARA and EPA, as well as DHA, should be supplied during the hatchling stage of Sepia. While designing an inert diet, which ensures normal growth and development of this species during the hatchling stage, the C18 FA and LC-PUFA levels and ratios should be considered, since the esterification pattern detected in the present study suggested competition between these FA for esterification into specific lipid classes. Moreover, considering the observed esterification pattern of LC-PUFA into different lipid classes, it is likely that the DHA/EPA/ARA ratio, rather than DHA/EPA or EPA/ARA ratios, would be of great importance for S. officinalis hatchling development. (C) 2015 Elsevier B.V. All rights reserved.