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Chantier qualité GA; Skeletal deformities are important traits for aqua-culture as they induce slow growing and low market value. We studied their genetic determinism and their interactions with the environment at the ongrowing stage in 5839 European sea bass from a partial factorial mating of 33 sires and 23 dams, reared in four sites. All families were mixed, and fish were first reared in one site (site B) until 35 g mean weight, then distributed to the four sites. A posteriori reconstruction of pedigree with microsatellites was used. Deformities were scored internally at slaughtering, and externally from photographs. Site B, where all fish were initially stocked until 35 g and exposed to forced swimming because of fast water current showed the highest rate of deformities with 83% and 65% from internal and external scoring respectively. Heritability on the underlying scale wash 2 =0.25±0.03 across all sites, and varied little between sites, while genetic correlations of deformities between sites were always high (>0.85). Genetic correlations between deformities and daily growth coefficient were variable between sites(rA=0.50±0.09, 0.43±0.10, 0.32±0.10, 0.18±0.10 for sites A, B, C, D respectively) and were positively linked with the average growth rate in each site. These results pointed out that there could be a relation between growth rate and the evolution of deformities at the grow-out stage.

Malformations in farmed fish are a prime research topic as it has a major impact on fish welfare and on the economical value of the product. In this study, the genetic component of spine deformities was estimated in European sea bass, a major species of Mediterranean aquaculture, with the use of a posteriori reconstruction of pedigree with microsatellites. Our population exhibited a very high malformation rate (81%),probably due to intense swimming of fish during pre-growing The heritability of global spine deformities was evaluated to be 0.21 +/- 0.04 on the underlying scale (033 +/- 0.06 for lordosis, 0.13 +/- 0.04 for scoliosis). Deformities scored by an internal or external examination turned out to be genetically the same trait (genetic correlations>0.9), although phenotypic correlations were moderate to high (0.45 +/- 0.04 to 0.92 +/- 0.01) due to difficulties in scoring the less severe deformities. Along time (from 100 to 800 g mean weight), lordosis had a constant heritability, with very high genetic correlations between stages (>0.9). its incidence increased from 39 to 53% indicating that the malformation was probably present from the beginning of the rearing period but that its expression increased overtime. A positive linkage between spine deformities and growth rate was demonstrated both by the higher early weight of affected fish and by the positive genetic correlation between weight and malformation (from 0.21 +/- 0.15 to 0.40 +/- 0.14), although deformities have a negative phenotypic impact on growth. However, heritabilities of malformation traits calculated here are only estimates that may indirectly describe the sensitivity of fish to the particular pre-growing environment as a function of different body weight genotypes. A quantification of realised heritability would therefore be necessary before concluding on the existence of a genetic basis for spinal malformations such as lordosis and scoliosis. Nevertheless and by precaution, selection for fast growth rate needs careful monitoring of deformities, and selection against malformations may counteract impacts of selection for fast growth. (c) 2009 Elsevier B.V. All rights reserved.

Genetic parameters for carcass quality traits were estimated in 27 families of sea bass (3 dams x 9 sires factorial mating design), raised mixed in the same tanks starting before hatching. O. spring parentage was determined a posteriori using 6 microsatellite loci. Carcass quality traits were recorded at 818 days post fertilization (mean standard length: 32.6 +/- 3.1 cm). Genetic parameters were estimated from the sire half sib variance and covariance components. Heritability of body weight (BW) and carcass processing traits (standardized to body weight) percent head weight (Head%), percent viscera weight (Viscera%) and percent visceral fat weight (VisceFat%) were relatively high ranging from 0.48 +/- 0.15 (Viscera%) to 0.87 +/- 0.23 (Head%); the estimate of heritability for fillet yield (Fillet%) was lower (0.25 +/- 0.10) but was significantly greater than zero. Body weight was positively correlated to Fillet%, Viscera%, and VisceFat%, and negatively correlated to Head%. These results indicate that these carcass processing traits can be modified by directional selection and that selection for greater BW would lead to an increase of Fillet%, Viscera% and VisceFat% and a decrease of Head%. Muscle lipid content (MuscleLipid%) was determined using two indirect methods: measurements with a Torry Fish Fatmeter (R) (TorryLipid) and determination of the percentage of dry matter content (MuscleDry%) via desiccation. Both measures were highly correlated to chemical measurements of MuscleLipid%. Regression analysis indicated a superior predictive value of TorryLipid suggesting that MuscleLipid% may be evaluated via rapid, non lethal measurements with a Torry Fish Fatmeter. Heritability estimates of TorryLipid and MuscleDry% differed significantly from zero (TorryLipid: 0.28 +/- 0.12, MuscleDry%: 0.36 +/- 0.14) indicating that MuscleLipid% could be lowered by directional selection. TorryLipid and MuscleDry% were weakly correlated to body weight and carcass processing traits suggesting that simultaneous improvement of MuscleLipid% and other carcass quality traits may require definition of multi-trait selection indices.

ATM-MNHN 'Formes possibles, formes realisees'; ATM-MNHN 'Biodiversite actuelle et fossile' We thank R. Hutterer, J. Lusby, C. and F. Nantet, V. Nicolas, E. Stoetzel, D. Tosh, S. Valenzuela, J. M. Lopez Garcia, and P. Vogel for granting access to specimens or loaning them. We also thank ATM-MNHN 'Formes possibles, formes realisees' and ATM-MNHN 'Biodiversite actuelle et fossile' for supporting our work. We thank Sibyle Moulin for her help with the final version. We would also like to pay tribute to Michel Pascal, a great scientist full of human qualities, who unfortunately left us during this project. We will not forget what we owe him. We would like to thank two anonymous reviewers for constructive comments on an earlier version of the paper.; International audience; Competition for resources has long been considered a major driver of evolution by natural selection. Thus, the ability to gain access to resources not available to other individuals and species should be under strong selection. In the present study, we focus on the potential role of biting in a shrew (Crocidura russula) because this trait may confer two advantages: (1) a broadening of the dietary niche and (2) the provision of direct superiority in interspecific interactions. The model chosen is the greater white-toothed shrew, which is considered as invasive in northern Europe and which is also known to displace native species of shrew in this area. Moreover, its distribution appears to constrain the distributional ranges of other species of shrew in the Maghreb. We use geometric morphometrics and a simple biomechanical model to describe shape variation and to evaluate the mechanical potential of the mandible of ten species of white-toothed shrews, with a special emphasis on C. russula and Crocidura suaveolens. We find that C. russula possesses an intermediate mechanical potential linked with an intermediate level of shape variability. Our results suggest that the higher mechanical potential may explain the observed pattern of colonization of the Atlantic islands by C. russula at the expense of C.suaveolens. Finally, our results also suggest that the ability to bite hard may be under strong selection in shrews.(c) 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114, 795-807.

International audience; Use of SNPs has been favoured due to their abundance in plant and animal genomes, accompanied by the falling cost and rising throughput capacity for detection and genotyping. Here, we present in vitro (obtained from targeted sequencing) and in silico discovery of SNPs, and the design of medium-throughput genotyping arrays for two oyster species, the Pacific oyster, Crassostrea gigas, and European flat oyster, Ostrea edulis. Two sets of 384 SNP markers were designed for two Illumina GoldenGate arrays and genotyped on more than 1000 samples for each species. In each case, oyster samples were obtained from wild and selected populations and from three-generation families seg-regating for traits of interest in aquaculture. The rate of successfully genotyped polymorphic SNPs was about 60% for each species. Effects of SNP origin and quality on genotyping success (Illumina functionality Score) were analy-sed and compared with other model and nonmodel species. Furthermore, a simulation was made based on a subset of the C. gigas SNP array with a minor allele frequency of 0.3 and typical crosses used in shellfish hatcheries. This simulation indicated that at least 150 markers were needed to perform an accurate parental assignment. Such panels might provide valuable tools to improve our understanding of the connectivity between wild (and selected) popula-tions and could contribute to future selective breeding programmes.

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Autre UE participante : UE0937 PEIMA Pisciculture Expérimentale INRA des Monts d'Arrée; absent

Genetic parameters of production traits (growth, carcass yield, fillet yield) and bony tissues (head and vertebral axis) were estimated for large all-female rainbow trout Oncorhynchus mykiss reared in freshwater. Genetic parameters were estimated using REML at 16 months of age (1636 g) on 1962 DNA-assigned progenies from a partial factorial mating design with 60 dams and 100 sex-reversed sires. Most traits presented medium to high heritability (0.37 to 0.54). A high genetic correlation (r(A)=0.97) was found between fillet yield and headless gutted carcass yield (or HGCarc%). Due to its higher heritability and high genetic correlation with fillet yield, selection on HGCarc% should result in a 50% increase in selection efficiency on fillet yield by reducing operator-linked variability at filleting. However, strong negative genetic correlations were estimated between body weight or fillet yield and bony tissue development as head yield or the head and vertebral column yield (-0.48 to -0.57). Ten generations of selection on body weight (or fillet yield) are, therefore, predicted to decrease the relative head development by 25 to 30% for slaughtering at constant age. As it is impossible to disentangle this result from a correlation that is only mathematically determined, this result needs further investigations. If yields are corrected according to their allometric relationship with body weight, only selection for fillet yield will decrease the proportion of bony tissues for a slaughtering at a constant body weight. Whatever the final objective of selection (to increase body weight or to shorten the production cycle at constant body weight), it is concluded that at least selection on fillet yield will affect the relative head and the vertebral axis development and that selection on growth may affect bony tissue development. These results are discussed in relation to the past results from livestock breeding, resource energy allocation theory and a future improvement of robustness by selection. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.

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Short Communication; absent

WOS: 000280735200051, Two hundred fifty three full-sib families from 33 males and 23 females of European seabass were produced in a partly factorial mating design. All fish were reared in the same tank for 14 months until reaching mean weight of 35 g. then 7000 of them were individually tagged and weighed, and dispatched to four farms in different locations (France, Israel, Italy and Portugal) representing a wide variety of environmental conditions. Around mean weight of 400 g. 1177 to 1667 fish at each site were weighed. Daily growth coefficient (DGC) was calculated. Pedigrees were successfully redrawn for 99.2% of fish using microsatellite markers. Genetic correlations between sites were high for body weight (>0.80 in all cases but one, i.e., five cases over six), but only moderate for DGC (0.21-0.61), with one exception. This indicates significant G x E interactions for growth rate, which were not revealed when studying body weight due to shared common environment of the fish prior to separation to the different rearing environments. (C) 2010 Elsevier B.V. All rights reserved., ECEuropean Commission Joint Research CentreEuropean Community (EC) [Q5CR-2002-71720]; INRA and Ifremer, This work was carried out within the framework of CRAFT project no. Q5CR-2002-71720 (Heritabolum) funded by the EC and the private farms, Panittica Pugliese (Italy), Viveiro Villanova (Portugal) and Ardag (Israel), which are also thanked for their active participation. The present work was also part of the program of the Research Group 'Amelioration Genetique des Poissons' between INRA and Ifremer.

International audience; L’expédition Santo 2006 s’est fixée pour objectif de réaliser l’inventaire le plus exhaustif possible de la biodiversité, tant marine que terrestre et dulçaquicole, de l’île océanique tropicale d’Espiritu Santo (Vanuatu, ex-Nouvelles-Hébrides), située dans le Pacifique Ouest (voir carte).Cette expédition est la suite logique de trois autres, exclusivement marines celles-là, qui se sont déroulées en Nouvelle-Calédonie (Lifou, 2000), aux Îles Australes (Rapa, 2002) et aux Philippines (Panglao, 2004). Ces quatre expéditions ont, entre autres objectifs communs, de valider l’existence d’un déclin de la diversité des espèces, depuis l’Asie du Sud-est, considérée actuellement comme la région la plus riche du monde, jusqu’à l’est de la Polynésie (îles Australes).L’expédition Santo 2006, qui s’est déroulée du début du mois d’août au début du mois de décembre 2006, a été organisée conjointement par le Muséum national d’histoire naturelle, l’Institut de recherche pour le développement et Pro-Natura International. Elle a mobilisé sur place 203 personnes, dont 153 scientifiques de 25 nationalités, selon quatre modules ou thèmes : « Biodiversité marine », « Forêts, Montagnes et Rivières », « Karst » et « Friches et Aliens ». Son budget global, hors salaire des scientifiques, est estimé à 1 100 000 Euros.