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BLANCHETON, J. - P., Attramadal, K. J. K., MICHAUD, L., ROQUE D'ORBCASTEL, E., & Vadstein, O. (2013). Insight into bacterial population in aquaculture systems and its implication. Aquacultural Engineering, 53, 30–39.
Résumé: The current onshore aquaculture trend is to develop large scale production of diversified fingerlings and very large units for fish ongrowing. This requires an industrial type of approach including quality assurance and minimization of failures in addition to management of bio-technical and economic aspects. Therefore, all the key biological mechanisms involved in Recirculating Aquaculture Systems (RAS) need to be better understood, especially those determining the development of bacterial populations and their interactions with fish. This review presents new knowledge on bacterial community compositions in various parts of RAS and on bacterial-fish interactions in RAS, which constitute essential tools for system management. (C) 2012 Elsevier B.V. All rights reserved.
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BLANCHETON, J. - P., BOSC, P., HUSSENOT, J., ROQUE D'ORBCASTEL, E., & ROMAIN, D. (2009). The 'new' European fish culture systems: Recirculating systems, offshore cages, integrated systems. Cahiers Agricultures, 18(2), 227–234.
Résumé: Over the last few decades, European fish culture was developed mainly as a intensive monospecific activity. In most countries, marine aquaculture cannot continue to develop on the shore line where it first settled due to high competition with other activities. It has now to move either offshore or into recirculation systems located in less occupied spaces. Fresh water availability and impact of fish production farms on the environment are strongly restraining the development of the activity, which is even declining in some countries such as France. Recirculation systems make it possible to decrease water consumption and facilitate waste treatment. Their economical feasibility is being demonstrated and they offer an alternative to developing fish farms. Whatever the rearing system, nutrients of feed are partially converted into fish flesh and most of them are thrown back as wastes into the environment. Integrated systems make it possible to convert such nutrients into algae, molluscs or fish and to release purified water. This article presents some aspects of the development of three types of rearing systems which are increasingly used in northern Europe: offshore cage culture, recirculation systems and integrated systems.
Mots-Clés: Pisciculture; Offshore structures; Integrated management; Fish cages; Europe
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Blasco, F. R., McKenzie, D. J., Taylor, E. W., & Rantin, F. T. (2017). The role of the autonomic nervous system in control of cardiac and air-breathing responses to sustained aerobic exercise in the African sharptooth catfish Clarias gariepinus. Comp. Biochem. Physiol. A-Mol. Integr. Physiol., 203, 273–280.
Résumé: Clarias gariepinus is a facultative air-breathing catfish that exhibits changes in heart rate (f(H)) associated with air breaths (AB). A transient bradycardia prior to the AB is followed by sustained tachycardia during breath-hold. This study evaluated air-breathing and cardiac responses to sustained aerobic exercise in juveniles (total length similar to 20 cm), and how exercise influenced variations in f(H) associated with AB. In particular, it investigated the role of adrenergic and cholinergic control in cardiac responses, and effects of pharmacological abolition of this control on air-breathing responses. Sustained exercise at 15, 30 and 45 cm s(-1) in a swim tunnel caused significant increases in f(AB) and f(H), from approximately 5 breaths h(-1) and 60 heartbeats min(-1) at the lowest speed, to over 60 breaths h(-1) and 100 beats min(-1) at the highest, respectively. There was a progressive decline in the degree of variation in f(H), around each AB, as f(AB) increased with exercise intensity. Total autonomic blockade abolished all variation in fH during exercise, and around each AB, but f(AB) responses were the same as in untreated animals. Cardiac responses were exclusively due to modulation of inhibitory cholinergic tone, which varied from >100% at the lowest speed to <10% at the highest. Cholinergic blockade had no effect on f(AB) compared to untreated fish. Excitatory beta-adrenergic tone was approximately 20% and did not vary with swimming speed, but its blockade increased f(AB) at all speeds, compared to untreated animals. This reveals complex effects of autonomic control on air-breathing during exercise in C. gariepinus, which deserve further investigation. (C) 2016 Elsevier Inc. All rights reserved.
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Bodiguel, X., Maury, O., Mellon-Duval, C., Roupsard, F., Le Guellec, A. - M., & Loizeau, V. (2009). A dynamic and mechanistic model of PCB bioaccumulation in the European hake (Merluccius merluccius). Journal of Sea Research, 62(2-3), 124–134.
Résumé: Bioaccumulation is difficult to document because responses differ among chemical compounds, with environmental conditions, and physiological processes characteristic of each species. We use a mechanistic model, based on the Dynamic Energy Budget (DEB) theory, to take into account this complexity and study factors impacting accumulation of organic pollutants in fish through ontogeny. The bioaccumulation model proposed is a comprehensive approach that relates evolution of hake PCB contamination to physiological information about the fish, such as diet, metabolism, reserve and reproduction status. The species studied is the European hake (Merluccius merluccius, L. 1758). The model is applied to study the total concentration and the lipid normalised concentration of 4 PCB congeners in male and female hakes from the Gulf of Lions (NW Mediterranean sea) and the Bay of Biscay (NE Atlantic ocean). Outputs of the model compare consistently to measurements over the life span of fish. Simulation results clearly demonstrate the relative effects of food contamination, growth and reproduction on the PCB bioaccumulation in hake. The same species living in different habitats and exposed to different PCB prey concentrations exhibit marked difference in the body accumulation of PCBs. At the adult stage, female hakes have a lower PCB concentration compared to males for a given length. We successfully simulated these sex-specific PCB concentrations by considering two mechanisms: a higher energy allocation to growth for females and a transfer of PCBs from the female to its eggs when allocating lipids from reserve to eggs. Finally, by its mechanistic description of physiological processes, the model is relevant for other species and sets the stage for a mechanistic understanding of toxicity and ecological effects of organic contaminants in marine organisms.
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Bodin, N., Chassot, E., Sardenne, F., Zudaire, I., Grande, M., Dhurmeea, Z., et al. (2018). Ecological data for western Indian Ocean tuna. Ecology, 99(5), 1245.
Résumé: Tuna are marine apex predators that inhabit the tropical and sub-tropical waters of the Indian Ocean where they support socially and economically important fisheries. Key component of pelagic communities, tuna are bioindicator species of anthropogenic and climate-induced changes through modifications of the structure and related energy-flow of food webs and ecosystems. The IndianEcoTuna dataset provides a panel of ecological tracers measured in four soft tissues (white muscle, red muscle, liver, gonads) from 1,364 individuals of four species, i.e., the albacore (ALB, Thunnus alalunga), the bigeye (BET, T. obesus), the skipjack (SKJ, Katsuwomus pelamis), and the yellowfin (YFT, T. albacares), collected throughout the western Indian Ocean from 2009 to 2015. Sampling was carried out during routine monitoring programs, at sea by observers onboard professional vessels or at landing. For each record, the type of fishing gear, the conservation mode, as well as the fishing date and catch location are provided. Individuals were sampled to span a wide range of body sizes: 565 ALB with fork length from 58 to 118 cm, 155 BET from 29.5 to 173 cm, 304 SKJ from 30 to 74 cm, and 340 YFT from 29 to 171.5 cm. The IndianEcoTuna dataset combines: (1) 9,512 records of carbon and nitrogen stable isotopes (percent element weights, δ13C and δ15N values) in 1,185 fish, (2) 887 concentrations of total proteins in 242 fish, (3) 8,356 concentrations of total lipids and three lipid classes (triacylglycerols TAG; phospholipids PL; sterols ST) in 695 fish, and (4) 1,150 and 1,033 profiles of neutral and polar fatty acids in 397 and 342 fish, respectively. Information on sex and weights of the whole fish, gonads, liver and stomach is provided. Because of the essential trophic role and wide-ranging of tuna in marine systems, and the large panel of tropho-energetic tracers and derived-key quantitative parameters provided (e.g., niche width, trophic position, condition indices), the IndianEcoTuna dataset should be of high interest for global and regional research on marine trophic ecology and food web analysis, as well as on the impacts of anthropogenic changes on Indian Ocean marine ecosystems. There are no copyright restrictions for research and/or teaching purposes. Usage of the dataset must include citation of this Data Paper.
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