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Sant Carles de la Ràpita, Spain

Carrasco N.,IRTA Sant Carles de la Rapita | Green T.,Macquarie University | Itoh N.,University of Tokyo
Journal of Invertebrate Pathology | Year: 2015

Marteilia spp. parasites are Paramyxean organisms that affect several commercial species of molluscs, and thus have a socio-economical impact. These parasites also have an ecological impact on the biodiversity and population dynamics of natural mollusc beds. It has been over forty years since the first description of Marteilia refringens, the first Marteilia species described. Despite four decades of research, the biology, cellular development, as well as the life cycle of Marteilia parasites are not fully understood. In recent years, new studies have reported advances in knowledge of the life cycle, the description of new species, the development of new molecular detection/discrimination tools, new data on biotype geographical distribution, as well as new information on host response and defence mechanisms. Such information is summarized, reported and discussed in the present review in order to facilitate a new overview of the subject. However, numerous knowledge gaps are still unresolved and need to be prioritized in the research and funding institution agendas. © 2015 Elsevier Inc.

Valles R.,IRTA Sant Carles de la Rapita | Estevez A.,IRTA Sant Carles de la Rapita
Aquaculture | Year: 2013

Meagre is a new candidate for Mediterranean aquaculture due to its fast growth in sea cages and good quality. Two experiments were designed in order to study the effect of photoperiod and light intensity on larval survival and specific growth rate (SGR) for days 1-15 (SGR1-15) and days 16-30 (SGR16-30). Overall larval survival was unaffected by light intensity (50 to 1000 lux) with rearing in 16. h light and ranged from 10% to 15%. Under a light intensity of 500 lux, decreasing photoperiod length significantly improved survival, increasing from 6% with rearing in 24. h light to 48% with 8. h light. SGR1-15 was unaffected by any of the light intensity and photoperiod regimes that were tested. However, SGR16-30 was highest for a light intensity of 500 lux with 16. h and 24. h light when compared with 12. h and 8. h light. High light intensity and induced a deleterious effect on larvae increasing mortality either due to cannibalism or swim bladder over-inflation. © 2012 Elsevier B.V.

Andres M.,IRTA Sant Carles de la Rapita | Rotllant G.,IRTA Sant Carles de la Rapita | Zeng C.,James Cook University
Aquaculture | Year: 2010

The blue swimmer crab is a commercially important species of the tropical Indo-Pacific regions that shows substantial potential as a candidate species for aquaculture. Optimization of larval rearing conditions, including photoperiod, is therefore important to establish a method for the intensive hatchery culture of this species. Newly hatched larvae of Portunus pelagicus in first zoeal stage (ZI) were reared under five photoperiod regimes 0L: 24D, 6L: 18D, 12L: 12D, 18L: 6D, and 24L: 0D (5 replicates per treatment) till they metamorphosed to megalopae (ranged from 8.5 ± 0.3 days (18L: 6D) to 10.8 ± 1.8 days (0L: 24D) at 29 ± 1 °C). Daily, larvae of each treatment were fed an identical diet of mixed rotifer and Artemia nauplii, and the survival and molt to successive stages was monitored. Newly hatched ZI larvae of P. pelagicus could successfully develop to the megalopal stage under all tested photoperiod conditions, but we detected significant differences in survival among treatments (p < 0.05). The constant darkness treatment (0L: 24D) had the lowest (19.2 ± 7.2%, mean ± S.E.) cumulative survival from ZI to the megalopal stage, while the 18L: 6D treatment achieved the highest survival (51.2 ± 23.6%). Similarly, the photoperiod significantly affected zoeal development. Constant darkness led to the longest cumulative zoeal duration (10.8 ± 1.8 days), whereas the 18L: 6D treatment rendered the shortest larval development (8.5 ± 0.3 days). In addition, larvae reared under constant darkness resulted in the smallest megalopae (carapace length = 1.44 ± 0.09 mm) and the lowest dry weight (0.536 ± 0.188 mg). In conclusion, photoperiod significantly affected the survival, development, and growth of P. pelagicus zoeal larvae. Constant darkness led to the lowest larval survival and developmental rate, while a photoperiod regime of 18L: 6D appeared to be the most suitable condition for the rearing of zoeal larvae of P. pelagicus. © 2010 Elsevier B.V. All rights reserved.

Norambuena F.,IRTA Sant Carles de la Rapita | Norambuena F.,Deakin University | Estevez A.,IRTA Sant Carles de la Rapita | Mananos E.,Institute of Aquaculture of Torre la Sal | And 3 more authors.
General and Comparative Endocrinology | Year: 2013

Previous studies on Senegalese sole (Solea senegalensis) indicated that cultured broodstock (first generation, G1) have lower tissue levels of arachidonic acid (20:4n-6, ARA) than wild counterparts. ARA is metabolized to form prostaglandins (PGs) that are involved in steroid production and follicle maturation in fish. In the present study the effects of different dietary levels of ARA on blood lipid and fatty acid composition, prostaglandin (PGF2α, PGF3α, PGE2 and PGE3) levels and plasmatic steroid levels (11-ketotestosterone, 11-KT, testosterone, T and estradiol, E2) in G1 Senegalese sole were studied. For this purpose, 12 groups of ten fish (1:1 male and female), were fed six diets (each diets was fed to two groups) with different dietary ARA levels over nine months (diets A.=0.7, B.=1.6, C.=2.3, D.=3.2, E.=5.0, F.=6.0% ARA). ARA and CHOL levels in blood showed a significant increase in an ARA dose related manner (P<. 0.05) whereas EPA and EPA/ARA ratio were reduced. In males, steroid (11-KT and T) levels increased significantly with increasing dietary ARA in a dose dependent manner, whereas in females E2 did not show any change related to dietary ARA content. Plasma concentration of 3-series PGs (i.e., PGE3 and PGF3α) were reduced in parallel to increased ARA levels in blood (P<. 0.05) and levels of PGs 3-series were always higher than 2-series PGs (PGE2 and PGF2α). In conclusion there is an effect of dietary ARA on steroid production of Senegalese sole males, which might have important consequences in the reproduction of cultured fish. © 2013 Elsevier Inc.

Norambuena F.,IRTA Sant Carles de la Rapita | Mackenzie S.,Autonomous University of Barcelona | Bell J.G.,University of Stirling | Callol A.,Autonomous University of Barcelona | And 2 more authors.
General and Comparative Endocrinology | Year: 2012

Prostaglandin levels in different tissues and cyclooxygenase (COX-2) gene expression were compared between wild and cultured Senegalese sole (. Solea senegalensis) broodstock in which a significantly different fatty acid profile, particularly lower tissue levels of arachidonic acid (ARA, 20:4. n-6) and higher levels of eicosapentaenoic acid (EPA, 20:5. n-3) in the cultured fish compared to wild had already been described. This is the first report of the COX-2 mRNA expression in Senegalese sole. Cyclooxygenase (COX-2) mRNA expression and prostaglandin (2- and 3-series) levels were determined in tissues from 32 broodstock fish, 16 (8 males and 8 females) from each origin wild and cultured (G1). Transcripts of COX-2 were highly expressed in gills, sperm-duct (s-duct), testis, oviduct and spleen compared to liver, kidney and muscle. Differences in COX-2 transcripts expression were found in response to the origin of the fish and expression was significantly higher in s-duct and gills from wild fish compared to cultured. Wild fish showed significantly higher levels of total 2-series PGs and lower levels of 3-series compared to cultured fish. The significance of the lower COX-2 expression and lower PG 2-series production in some of the tissues of cultured fish was discussed in relation to the previously described differences in fatty acid profile (lower tissue levels of ARA and higher levels of EPA and EPA/ARA ratio in cultured fish) and the reproductive failure to spawn viable eggs from G1 cultured Senegalese sole compared to successful spawning from captive wild broodstock. © 2012 Elsevier Inc.

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