Search results for " Dicentrarchus labrax"

Preliminary Study on the In vitro and In vivo Effects of Asparagopsis taxiformis Bioactive Phycoderivates on Teleosts

2016

Several compounds from marine organisms have been studied for their potential use in aquaculture. Among the red algae, Asparagopsis taxiformis is considered one of the most promising species for the production of bioactive metabolites with numerous proposed applications. Here, the in vitro antibacterial activity, the easy handling and the absence of adverse effects on marine fish species are reported. Depending on the seasonal period of sampling, ethanol extracts of A. taxiformis exhibited significantly different inhibitory activity against fish pathogenic bacteria. The extract obtained in late spring showed strong antibacterial activity against Aeromonas salmonicida subsp. salmonicida, Vib…

Surgical implantation of electronic tags does not induce medium-term effect: insights from growth and stress physiological profile in two marine fish…

2020

Abstract Background Telemetry applied to aquatic organisms has recently developed greatly. Physiological sensors have been increasingly used as tools for fish welfare monitoring. However, for the technology to be used as a reliable welfare indicator, it is important that the tagging procedure does not disrupt fish physiology, behaviour and performance. In this communication, we share our medium-term data on stress physiological profile and growth performance after surgical tag implantation in two important marine fish species for European aquaculture, the sea bream (Sparus aurata) and the European sea bass (Dicentrarchus labrax). Results Blood samples after surgical tag implantation (46 day…

Gonadal sexual differentiation of European sea bass (Dicentrarchus labrax, L. 1758) of fingerlings in different size classes

2016

This report describes a study of the gonad differentiation in fingerlings of European sea bass (Dicentrarchus labrax) belonging to different size groups. Fishes were divided into four groups according to their weight: Group 1 (4.5 ± 0.7 g), Group 2 (9.2 ± 0.8 g), Group 3 (14.8 ± 1.8 g), and Group 4 (21.8 ± 2.3 g). In all groups, low percentages of undifferentiated or early sexually differentiated fish were found. Higher percentages of fully differentiated ovaries were found in Groups 1 and 3. Fully differentiated testes occurred in 90% of Group 4. Ninety percent of fish in Group 2 had gonads with intratesticular oocytes. This highlights the occurrence of intersexual cases and suggests that …

Economic comparison between offshore and inshore aquaculture production systems of European sea bass in Italy

2014

Abstract Offshore production system is predicted to increase in the near future driven by the lack of coastal space and lower environmental impacts. The aim of this paper has been to evaluate the economic performance of offshore production system respect to inshore one, by comparing net present value (NPV), discounted payback time (DPBT) and internal rate of return (IRR) of two Italian mariculture farms that produce European sea bass. Results showed a better economic profitability of offshore farm, even if sensitivity analysis revealed that financial indicators of both aquaculture production systems have been very sensitive to market condition changes. So, offshore production system could r…

Espressione e distribuzione del recettore DLGR1 nel cervello del teleosteo Dicentrarchus labrax (L. 1758)

2008

Glucocorticoid receptor (DlGR1) is expressed in pre-larval and larval stages of the teleost fish Dicentrarchus labrax.

2008

Glucocorticoid hormone receptors (GR), members of the nuclear hormone receptor superfamily, are ligand-dependent transcription factors expressed in various tissues by binding to specific DNA sequences. Since glucocorticoids have a role in maintaining the homeostatic status in fish, we previously cloned and sequenced a GR (DlGR1) of adult Dicentrarchus labrax; we also showed mRNA expression (in situ hybridization) and tissue immunohistochemical localization of DlGR1 in several organs. This work has now been extended to the examination of the expression, tissue distribution, and cytolocalization of DlGR1 in larval developmental stages by similar methods to those used for the adult organs. The…

Serum lectins in fish innate immunity: molecular and functional aspects

2007

Fucose-binding lectins (FBL) are present in tissues and fluids from invertebrates and vertebrates. The lectin repertoires in teleost fish are highly diversified and recently has been described the structure of the fucose-binding agglutinin that revealed a novel lectin fold (the “F-type” eel (Anguilla anguilla) fold), which shared a unique fucose-binding sequence motif contained both in carbohydrate-binding proteins and unrelated proteins. In this report, we describe serum FBL from sea bass Dicentrarchus labrax and sea bream Sparus aurata. These lectins were purified, characterized, cloned and sequenced. Studies on structural aspects, biological activity, tissue distribution as well as ontog…

Welfare status of cage farmed European sea bass (Dicentrarchus labrax): A comparison between submerged and surface cages

2011

Abstract Submersible sea-cages represent an alternative method to standard surface-based cages, and could help solve several production problems that exist in surface-based farming, such as heavy storms, algal and jellyfish blooms and attacks by predators. In this study, we investigated growth, haematological, biochemical and immunological parameters of European sea bass ( Dicentrarchus labrax ) farmed in surface and submersible cages, to compare the physiological status under different rearing conditions. In addition, we evaluated the use of erythrocyte HSP70 levels as a biomarker of fish welfare. The study was conducted in two submerged and two surface cages filled with D. labrax . No sig…

Changes in behavioural response of Mediterranean Seabass (Dicenthratus labrax L.) under different feeding distributions

2009

Captive-induced behavioural deviations may involve many aspects of fish behaviour such as swimming activity and enhancement of individual aggressiveness. We studied seabass (Dicentrarchus labrax) behaviour as a function of manual and automatic feeding distribution modes. Under manual mode, the food is distributed over an extended area for a longer period, and its precise location is not always predictable, while with pneumatic automatic feeders, fish receive the same amount of resource, which is concentrated in the same surface area over a shorter period. We compared seabass behaviour under automatic and manual conditions collecting video image recordings before, during, and after feeding d…

Effetti dell'esposizione in vitro al cloruro di metilmercurio Sulle risposte immunitarie di Dicentrarchus labrax.

2008

This study shows that high methylmercury concentrations are cytotoxic for Dicentrarchus labrax leucocytes, whereas subletal concentrations affect leucocyte phagocytosis and cells morphology in a dose dependent fashion. Although the serum hemoagglutinating activity was not inhibited by the metal, the activity of purified serum F-lectin fraction and mucus was significantly decreased by relevant methylmercury concentrations.