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Auteur de Verdal, H.; Komen, H.; Quillet, E.; Chatain, B.; Allal, F.; Benzie, J.A.H.; Vandeputte, M. url  doi
openurl 
  Titre Improving feed efficiency in fish using selective breeding: a review Type Article scientifique
  Année 2017 Publication Revue Abrégée Rev Aquacult  
  Volume Numéro Pages (up)  
  Mots-Clés Feed conversion ratio; Feed efficiency; Feed intake; fish; Genetics; selection  
  Résumé Improving feed efficiency (FE) is key to reducing production costs in aquaculture and to achieving sustainability for the aquaculture industry. Feed costs account for 30–70% of total production costs in aquaculture; much work has been done on nutritional and husbandry approaches to improve FE but only a limited amount of research has been devoted to using genetics, despite its potential. This paper reviews past work to improve FE in fish using selective breeding and assess future directions. Direct selection on FE traits requires methods to measure individual feed consumption and estimate FE efficiently and accurately. This is particularly difficult to do in fish because of the environment in which they live. Many of the published studies on FE were found to be inaccurate because of methodological problems. The relatively low heritability estimates of FE traits in fish published to date are probably partly as a result of inaccurate measurements of feed intake. Improving ways to measure the individual feed intake with high accuracy will be critical to the successful application of genetics to improving FE. Indirect selection criteria that could be used to improve FE (including growth after starvation/refeeding, body composition, neuropeptides or hormone levels) are discussed. Promising approaches to measuring feed intake accurately that may enable these studies to be undertaken are identified. More work using these will be needed prior to assessing the practicality of the introduction of direct or indirect traits for FE in fish genetic improvement programmes.  
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  ISSN 1753-5131 ISBN Médium  
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Auteur Besson, M.; Allal, F.; Chatain, B.; Vergnet, A.; Clota, F.; Vandeputte, M. url  doi
openurl 
  Titre Combining Individual Phenotypes of Feed Intake With Genomic Data to Improve Feed Efficiency in Sea Bass Type Article scientifique
  Année 2019 Publication Revue Abrégée Front. Genet.  
  Volume 10 Numéro Pages (up)  
  Mots-Clés Aquaculture; Feed conversation ratio; Fine phenotyping; genomic selection; Individual feed intake; Restricted feeding; selective breeding  
  Résumé Measuring individual feed intake of fish in farms is complex and precludes direct selective breeding for feed conversion ratio (FCR). Here, we estimated the individual FCR of 588 sea bass using individual rearing under restricted feeding. These fish were also phenotyped for their weight loss at fasting and muscle fat content as possible indirect indicators of FCR. The 588 fish were from a full factorial mating between parental lines divergently selected for high (F+) or low (F-) weight loss at fasting. The pedigree was known back to the great grandparents. A subset of 400 offspring and their ancestors were genotyped for 1,110 SNPs, which allowed estimating the genomic heritability of traits. Individual FCR and growth rate in aquarium were both heritable (genomic h² = 0.47 and 0.76, respectively) and strongly genetically correlated (-0.98), meaning that under restricted feeding, faster growing fish were more efficient. FCR in aquariums was significantly better for fish with two F- parents (1.38), worse for fish with two F+ parents (1.51) and intermediate (1.46) for crossbred fish (F+/F- or F-/F+). Muscle fat content was positively genetically correlated to growth rate in aquarium and during fasting. Thus, higher growth rate in aquariums, lower weight loss at fasting and fat content are all traits that could improve FCR in aquarium. Improving these traits would also improve FCR of fish in normal group rearing conditions, as we showed that groups composed of fish with good individual FCR were significantly more efficient in groups. The FCR of groups was also better when the fish composing the groups had, on average, lower estimated breeding values for growth rate during fasting (losing less weight). Thus, FCR in aquarium and weight loss at fasting are both promising to improve FCR of fish in groups. Finally, we showed that the reliability of estimated breeding values was higher (from +10% to +125%) with single-step genomic BLUP than with pedigree-based BLUP, showing that genomic data would enhance the accuracy of EBV prediction o in selection candidates from a limited number of sibs individually phenotyped for FCR in aquariums.  
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  ISSN 1664-8021 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2542  
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Auteur Gueroun, S.K.M.; Molinero, J.C.; Piraino, S.; Daly Yahia, M.N. openurl 
  Titre Population dynamics and predatory impact of the alien jellyfish Aurelia solida (Cnidaria, Scyphozoa) in the Bizerte Lagoon (southwestern Mediterranean Sea) Type Article scientifique
  Année 2020 Publication Revue Abrégée Mediterr. Mar. Sci.  
  Volume 21 Numéro 1 Pages (up) 22-35  
  Mots-Clés abundance; asexual reproduction rates; aurita cnidaria; common jellyfish; cyanea-capillata; gullmar fjord; mesozooplankton; moon jellyfish; predation; prey selection; prince-william-sound; Scyphomedusae; SW Mediterranean; tokyo bay; zooplankton  
  Résumé Understanding the life cycle strategies and predatory impact of alien jellyfish species is critical to mitigate the impact that these organisms may have on local populations, biodiversity, and ultimately on the functioning of food webs. In the Mediterranean Sea, little is known about the dynamics of alien jellyfish, despite this biodiversity hotspot being one of the most threatened areas by increasing numbers of alien jellyfish. Here, we investigated the population dynamics and predatory impact of a non-indigenous scyphomedusa, Aurelia solida Browne 1905, in the Bizerte Lagoon, Tunisia. The study was based on bimonthly surveys performed over two consecutive years, from November 2012 to August 2014. Field observations showed that the planktonic phase of A. solida occurs from winter to early summer. Prey composition was investigated by means of gut content and field zooplankton analyses. Calanoid copepods, mollusc larvae, and larvaceans represented the main food items of A. solida. To determine the jellyfish feeding rate and their predatory impact on zooplankton populations, the digestion time for zooplankton prey was assessed at three different temperatures: 13, 18, and 23 degrees C in laboratory conditions, corresponding to the average range of temperatures encountered by A. solida in the Bizerte Lagoon. We found that A. solida consumed 0.5-22.5% and 0.02-37.3% of the daily zooplankton standing stock in 2013 and 2014, respectively. These results indicate a non-negligible but restricted seasonal grazing impact on some mesozooplankton groups, explained by the relatively short lifespan of the medusa stage (5-6 months).  
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  ISSN 1108-393x ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000524248700003 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2773  
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Auteur Jeanmougin, M.; Leprieur, F.; Lois, G.; Clergeau, P. url  doi
openurl 
  Titre Fine-scale urbanization affects Odonata species diversity in ponds of a megacity (Paris, France) Type Article scientifique
  Année 2014 Publication Revue Abrégée Acta Oecologica-International Journal of Ecology  
  Volume 59 Numéro Pages (up) 26-34  
  Mots-Clés Evenness; Landscape composition; Model averaging; Ponds; Species diversity; Urban ecology; agricultural landscape; comparative biodiversity; conservation; dragonflies odonata; ecology; fresh-water habitat; patterns; richness; selection; urban  
  Résumé Current developments in urban ecology include very few studies focused on pond ecosystems, though ponds are recognized as biodiversity hotspots. Using Odonata as an indicator model, we explored changes in species composition in ponds localized along an urban gradient of a megacity (Paris, France). We then assessed the relative importance of local- and landscape-scale variables in shaping Odonata alpha-diversity patterns using a model-averaging approach. Analyses were performed for adult (A) and adult plus exuviae (AE) census data. At 26 ponds, we recorded 657 adults and 815 exuviae belonging to 17 Odonata species. The results showed that the Odonata species assemblage composition was not determined by pond localization along the urban gradient. Similarly, pond characteristics were found to be similar among urban, suburban and periurban ponds. The analyses of AE census data revealed that fine-scale urbanization (i.e., increased density of buildings surrounding ponds) negatively affects Odonata alpha-diversity. In contrast, pond localization along the urban gradient weakly explained the alpha-diversity patterns. Several local-scale variables, such as the coverage of submerged macrophytes, were found to be significant drivers of Odonata alpha-diversity. Together, these results show that the degree of urbanization around ponds must be considered instead of pond localization along the urban gradient when assessing the potential impacts of urbanization on Odonata species diversity This work also indicates the importance of exuviae sampling in understanding the response of Odonata to urbanization. (C) 2014 Elsevier Masson SAS. 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 1146-609x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 602  
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Auteur Kappes, M.A.; Shaffer, S.A.; Tremblay, Y.; Foley, D.G.; Palacios, D.M.; Bograd, S.J.; Costa, D.P. url  doi
openurl 
  Titre Reproductive constraints influence habitat accessibility, segregation, and preference of sympatric albatross species Type Article scientifique
  Année 2015 Publication Revue Abrégée Movement Ecology  
  Volume 3 Numéro 1 Pages (up) 34  
  Mots-Clés Activity patterns; Black-footed albatross; Foraging behavior; Geolocation; Habitat selection; Laysan albatross; Satellite tracking; Spatial modeling; Spatial segregation  
  Résumé The spatiotemporal distribution of animals is dependent on a suite of factors, including the distribution of resources, interactions within and between species, physiological limitations, and requirements for reproduction, dispersal, or migration. During breeding, reproductive constraints play a major role in the distribution and behavior of central place foragers, such as pelagic seabirds. We examined the foraging behavior and marine habitat selection of Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses throughout their eight month breeding cycle at Tern Island, Northwest Hawaiian Islands to evaluate how variable constraints of breeding influenced habitat availability and foraging decisions. We used satellite tracking and light-based geolocation to determine foraging locations of individuals, and applied a biologically realistic null usage model to generate control locations and model habitat preference under a case–control design. Remotely sensed oceanographic data were used to characterize albatross habitats in the North Pacific.  
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  ISSN 2051-3933 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1460  
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