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Auteur de Verdal, H.; Mekkawy, W.; Lind, C.E.; Vandeputte, M.; Chatain, B.; Benzie, J.A.H. doi  openurl
  Titre Measuring individual feed efficiency and its correlations with performance traits in Nile tilapia, Oreochromis niloticus Type Article scientifique
  Année 2017 Publication Revue Abrégée Aquaculture  
  Volume 468 Numéro Pages (up) 489-495  
  Mots-Clés bream sparus-aurata; compensatory growth; conversion efficiency; diet environments; Feed conversion ratio; Feed efficiency; Feed intake; fish-meal; food; genetic-improvement; growth; Nile tilapia; rainbow-trout; Repeatability; salmon salmo-salar; selection; Sex  
  Résumé Estimating individual feed intake of fish held in groups has long been a challenge precluding precise knowledge of the individual variation of feed efficiency (FE) in fish. In this study, counts of the number of feed pellets (1.63 mg on average) eaten by individual tilapia (Oreochromis niloticus) held in 8 mixed sex groups of 15 fish were measured from video recordings made over a period of 10 days where fish were fed twice daily to achieve compensatory growth after 10 days of fasting. The initial body weight of the fish was 9.77 +/- 2.03 g. Accumulated measures of feed intake (FI) over 11 meals were found to achieve 95% repeatability and a high accuracy of estimation of FI. During the FI measurement period, the average fish growth was 12.0 +/- 3.6 g, feed intake was 0.99 g day (-1), and feed conversion ratio (FCR) was 0.86 +/- 0.20. FI differences accounted for 56% of the observed individual growth variations, and 44% was related to individual variations of FE. On average males grew 24.2% faster than females but consumed 12.1% more feed. Males showed an 11.7% better FCR than females, whereas residual feed intake (RFI) differences were not significant between sexes. FCR and RFI were moderately and significantly correlated (0.58 +/- 0.06) but FCR and FI, and body weight gain (BWG) and RFI, were not, highlighting the complex relationships between feed efficiency traits. The approach described here demonstrates a means to accurately investigate FE traits in fish and to assess the potential for their genetic improvement. Statement of relevance: Feed efficiency has strong economic and environmental impact. (C) 2016 Elsevier B.V. All rights reserved.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0044-8486 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1713  
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Auteur McLean, M.J.; Mouillot, D.; Goascoz, N.; Schlaich, I.; Auber, A. doi  openurl
  Titre Functional reorganization of marine fish nurseries under climate warming Type Article scientifique
  Année 2019 Publication Revue Abrégée Glob. Change Biol.  
  Volume 25 Numéro 2 Pages (up) 660-674  
  Mots-Clés English Channel; community; ecosystem; fisheries; recruitment; functional traits; in-situ; connectivity; estuarine; climate change; life-history strategies; ecosystem function; life history; english-channel; Atlantic Multidecadal Oscillation; atlantic multidecadal oscillation; fuzzy-logic; r-selection  
  Résumé While climate change is rapidly impacting marine species and ecosystems worldwide, the effects of climate warming on coastal fish nurseries have received little attention despite nurseries' fundamental roles in recruitment and population replenishment. Here, we used a 26-year time series (1987-2012) of fish monitoring in the Bay of Somme, a nursery in the Eastern English Channel (EEC), to examine the impacts of environmental and human drivers on the spatial and temporal dynamics of fish functional structure during a warming phase of the Atlantic Multidecadal Oscillation (AMO). We found that the nursery was initially dominated by fishes with r-selected life-history traits such as low trophic level, low age and size at maturity, and small offspring, which are highly sensitive to warming. The AMO, likely superimposed on climate change, induced rapid warming in the late 1990s (over 1 degrees C from 1998 to 2003), leading to functional reorganization of fish communities, with a roughly 80% decline in overall fish abundance and increased dominance by K-selected fishes. Additionally, historical overfishing likely rendered the bay more vulnerable to climatic changes due to increased dominance by fishing-tolerant, yet climatically sensitive species. The drop in fish abundance not only altered fish functional structure within the Bay of Somme, but the EEC was likely impacted, as the EEC has been unable to recover from a regime shift in the late 1990s potentially, in part, due to failed replenishment from the bay. Given the collapse of r-selected fishes, we discuss how the combination of climate cycles and global warming could threaten marine fish nurseries worldwide, as nurseries are often dominated by r-selected species.  
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  ISSN 1354-1013 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2523  
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Auteur Hillen, J.E.J.; Coscia, I.; Vandeputte, M.; Herten, K.; Hellemans, B.; Maroso, F.; Vergnet, A.; Allal, F.; Maes, G.E.; Volckaert, F.A.M. url  doi
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  Titre Estimates of genetic variability and inbreeding in experimentally selected populations of European sea bass Type Article scientifique
  Année 2017 Publication Revue Abrégée Aquaculture  
  Volume 479 Numéro Pages (up) 742-749  
  Mots-Clés Artificial selection; ddRAD; fish; genetic diversity; Genomics; Inbreeding  
  Résumé The aquaculture industry has increasingly aimed at improving economically important traits like growth, feed efficiency and resistance to infections. Artificial selection represents an important window of opportunity to significantly improve production. However, the pitfall is that selection will reduce genetic diversity and increase inbreeding in the farmed stocks. Genetic tools are very useful in this context as they provide accurate measures of genetic diversity together with many additional insights in the stock status and the selection process. In this study we assessed the level of genetic variability and relatedness over several generations of two lines of experimentally selected European sea bass (Dicentrarchus labrax L.). The first line was selected for growth over three generations and the second line for both high and low weight loss under a starvation regime over two generations. We used a genomic approach (2549 single nucleotide polymorphism markers derived from double digest restriction site associated DNA sequencing) in combination with eight microsatellites to estimate genetic variation, relatedness, effective population size and genetic differentiation across generations. Individual heterozygosity estimates indicated that the selected lines showed no significant reduction in diversity compared with wild populations. There was, however, a decreasing trend in allelic richness, suggesting the loss of low frequency alleles. We compared the estimates of effective population size from genetic markers with pedigree information and found good correspondence between methods. This study provides important insights in the genetic consequences of selective breeding and demonstrates the operational use of the latest genomic tools to estimate variability, inbreeding and at a later stage domestication and artificial selection.  
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  ISSN 0044-8486 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2183  
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Auteur Yates, K.L.; Bouchet, P.J.; Caley, M.J.; Mengersen, K.; Randin, C.F.; Parnell, S.; Fielding, A.H.; Bamford, A.J.; Ban, S.; Marcia Barbosa, A.; Dormann, C.F.; Elith, J.; Embling, C.B.; Ervin, G.N.; Fisher, R.; Gould, S.; Graf, R.F.; Gregr, E.J.; Halpin, P.N.; Heikkinen, R.K.; Heinanen, S.; Jones, A.R.; Krishnakumar, P.K.; Lauria, V.; Lozano-Montes, H.; Mannocci, L.; Mellin, C.; Mesgaran, M.B.; Moreno-Amat, E.; Mormede, S.; Novaczek, E.; Oppel, S.; Crespo, G.O.; Peterson, A.T.; Rapacciuolo, G.; Roberts, J.J.; Ross, R.E.; Scales, K.L.; Schoeman, D.; Snelgrove, P.; Sundblad, G.; Thuiller, W.; Torres, L.G.; Verbruggen, H.; Wang, L.; Wenger, S.; Whittingham, M.J.; Zharikov, Y.; Zurell, D.; Sequeira, A.M.M. doi  openurl
  Titre Outstanding Challenges in the Transferability of Ecological Models Type Article scientifique
  Année 2018 Publication Revue Abrégée Trends Ecol. Evol.  
  Volume 33 Numéro 10 Pages (up) 790-802  
  Mots-Clés abundance; biotic interactions; climate-change; decision-making; distributions; habitat selection; niche; predictive models; species distribution models; temporal transferability  
  Résumé Predictive models are central to many scientific disciplines and vital for informing management in a rapidly changing world. However, limited understanding of the accuracy and precision of models transferred to novel conditions (their 'transferability') undermines confidence in their predictions. Here, 50 experts identified priority knowledge gaps which, if filled, will most improve model transfers. These are summarized into six technical and six fundamental challenges, which underlie the combined need to intensify research on the determinants of ecological predictability, including species traits and data quality, and develop best practices for transferring models. Of high importance is the identification of a widely applicable set of transferability metrics, with appropriate tools to quantify the sources and impacts of prediction uncertainty under novel conditions.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0169-5347 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2447  
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Auteur Courbin, N.; Besnard, A.; Peron, C.; Saraux, C.; Fort, J.; Perret, S.; Tornos, J.; Gremillet, D. doi  openurl
  Titre Short-term prey field lability constrains individual specialisation in resource selection and foraging site fidelity in a marine predator Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecol. Lett.  
  Volume 21 Numéro 7 Pages (up) 1043-1054  
  Mots-Clés behavior; Behavioural consistency; Calonectris diomedea; diet; ecology; foraging site fidelity; gannets; habitat selection; mediterranean sea; models; movement; resource selection; Scopoli's shearwater; seabirds; strategies; temporal resource dynamic; Western Mediterranean  
  Résumé Spatio-temporally stable prey distributions coupled with individual foraging site fidelity are predicted to favour individual resource specialisation. Conversely, predators coping with dynamic prey distributions should diversify their individual diet and/or shift foraging areas to increase net intake. We studied individual specialisation in Scopoli's shearwaters (Calonectris diomedea) from the highly dynamic Western Mediterranean, using daily prey distributions together with resource selection, site fidelity and trophic-level analyses. As hypothesised, we found dietary diversification, low foraging site fidelity and almost no individual specialisation in resource selection. Crucially, shearwaters switched daily foraging tactics, selecting areas with contrasting prey of varying trophic levels. Overall, information use and plastic resource selection of individuals with reduced short-term foraging site fidelity allow predators to overcome prey field lability. Our study is an essential step towards a better understanding of individual responses to enhanced environmental stochasticity driven by global changes, and of pathways favouring population persistence.  
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  Auteur institutionnel Thèse  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1461-023x ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2380  
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