Likelihood and Bayesian analyses reveal major genes affecting body composition, carcass, meat quality and the number of false teats in a Chinese European pig line

Segregation analyses were performed using both maximum likelihood – via a Quasi Newton algorithm – (ML-QN) and Bayesian – via Gibbs sampling – (Bayesian-GS) approaches in the Chinese European Tiameslan pig line. Major genes were searched for average ultrasonic backfat thickness (ABT), carcass fat (X2 and X4) and lean (X5) depths, days from 20 to 100 kg (D20100), Napole technological yield (NTY), number of false (FTN) and good (GTN) teats, as well as total teat number (TTN). The discrete nature of FTN was additionally considered using a threshold model under ML methodology. The results obtained with both methods consistently suggested the presence of major genes affecting ABT, X2, NTY, GTN and FTN. Major genes were also suggested for X4 and X5 using ML-QN, but not the Bayesian-GS, approach. The major gene affecting FTN was confirmed using the threshold model. Genetic correlations as well as gene effect and genotype frequency estimates suggested the presence of four different major genes. The first gene would affect fatness traits (ABT, X2 and X4), the second one a leanness trait (X5), the third one NTY and the last one GTN and FTN. Genotype frequencies of breeding animals and their evolution over time were consistent with the selection performed in the Tiameslan line

Les ports antiques de Narbonne

Le projet collectif de recherche sur les ports antiques de Narbonne s’inscrit dans le cadre d’un partenariat entre la Région Languedoc-Roussillon, l’État et les collectivités. L’organisation du port antique de Narbonne restait méconnue à cause d’un important recouvrement sédimentaire et d’une histoire complexe. Le PCR s’attache à combler ces lacunes en continuant l’exploration des sites de Gruissan, Port-la-Nautique et Mandirac et en développant les prospections géophysiques. En ville, des en..

Characterisation of iron (II) sulfides in wet archaeological woods: the wreck of Mandirac (IV th century, antique ports of Narbonne, France)

International audienceThe wreck of Mandirac (Narbonne, France, IV century) was excavated in 2013 and 2014 from waterlogged soil. A magnetic prospection campaign performed in 2014 revealed that the wood was abnormally magnetic. A plank extracted from the hull, containing an iron nail, was analysed using Environmental Scanning Electron Microscopy, micro-Raman spectroscopy, X-Ray diffraction and magnetic characterization methods in order to identify the mineral composition inside the wood and of the nail. Results revealed an accumulation of greigite and pyrite in the wood around the nail, where the pH was measured below 3. The nail was completely corroded into pyrite and siderite, with no metal left. Marcasite was also identified far from the nail, where the pH was measured around 5. Greigite was the only phase responsible of the magnetic signal emitted from the wood and proved to be present in varying amounts throughout the entire wreck. The iron sulfides were probably formed via anaerobic sulphidogenic bacteria influenced corrosion processes, which occurred on the nails. These results are very different from those obtained from more recent shipwrecks (XIX century). So the nature of these iron sulfides in wet archaeological woods is discussed

Progeny-testing of full-sibs IBD in a SSC2 QTL region highlights epistatic interactions for fatness traits in pigs

<p>Abstract</p> <p>Background</p> <p>Many QTL have been detected in pigs, but very few of them have been fine-mapped up to the causal mutation. On SSC2, the <it>IGF2</it>-intron3-G3072A mutation has been described as the causative polymorphism for a QTL underlying muscle mass and backfat deposition, but further studies have demonstrated that at least one additional QTL should segregate downstream of this mutation. A marker-assisted backcrossing design was set up in order to confirm the segregation of this second locus, reduce its confidence interval and better understand its mode of segregation.</p> <p>Results</p> <p>Five recombinant full-sibs, with genotype G/G at the <it>IGF2 </it>mutation, were progeny-tested. Only two of them displayed significant QTL for fatness traits although four inherited the same paternal and maternal chromosomes, thus exhibiting the same haplotypic contrast in the QTL region. The hypothesis of an interaction with another region in the genome was proposed to explain these discrepancies and after a genome scan, four different regions were retained as potential interacting regions with the SSC2 QTL. A candidate interacting region on SSC13 was confirmed by the analysis of an F2 pedigree, and in the backcross pedigree one haplotype in this region was found to mask the SSC2 QTL effect.</p> <p>Conclusions</p> <p>Assuming the hypothesis of interactions with other chromosomal regions, the QTL could be unambiguously mapped to a 30 cM region delimited by recombination points. The marker-assisted backcrossing design was successfully used to confirm the segregation of a QTL on SSC2 and, because full-sibs that inherited the same alleles from their two parents were analysed, the detection of epistatic interactions could be performed between alleles and not between breeds as usually done with the traditional Line-Cross model. Additional analyses of other recombinant sires should provide more information to further improve the fine-mapping of this locus, and confirm or deny the interaction identified between chromosomes 2 and 13.</p

Holocene land-sea climatic links on the equatorial Pacific coast (Bay of Guayaquil, Ecuador)

Copyright © 2015 SAGE PublicationsWe analyzed the pollen content of a marine core located near the bay of Guayaquil in Ecuador to document the link between sea surface temperatures (SST) and changes in rainfall regimes on the adjacent continent during the Holocene. Based on the expansion/regression of five vegetation types, we observe three successive climatic patterns. In the first phase, between 11,700 and 7700 cal yr BP, the presence of a cloud (Andean) forest in the mid altitudes and mangroves in the estuary of the Guayas Basin, were associated with a maximum in boreal summer insolation, a northernmost position of the Intertropical Convergence Zone (ITCZ), a land- sea thermal contrast, and dryness. Between 7700 and 2850 cal yr BP, the expansion of the coastal herbs and the regression of the mangrove indicate a drier climate with weak ITCZ and low ENSO variability while austral winter insolation gradually increased. The interval between 4200 and 2850 cal yr BP was marked by the coolest and driest climatic conditions of the Holocene due to the weak influence of the ITCZ and a strengthening of the Humboldt Current. After 2850 cal yr BP, high variability and amplitude of the Andean forest changes occurred when ENSO frequency and amplitude increased, indicating high variability in land-sea connections. The ITCZ reached the latitude of Guayaquil only after 2500 cal yr BP inducing the bimodal precipitation regime we observe today. Our study shows that besides insolation, the ITCZ position and ENSO frequency, changes in eastern equatorial Pacific SSTs play a major role in determining the composition of the ecosystems and the hydrological cycle of the Ecuadorian Pacific coast and the Western Cordillera in Ecuador.Deutsche ForschungsgemeinschaftFrench Research Agenc

Narbonne : la ville et ses ports

A new reading of ancient documents and discoveries made recently in Narbonne and its surroundings have made possible to clarify the different stages of the urban development but also showed the existence of important portuary installations in the bodies of water, South of the town. The analysis of these information, to which we can add those related to the trading relationships existing with the hinterland, bring essential elements to the understanding of Narbonne in antic times.La reprise de la documentation ancienne et l'apport des découvertes récentes réalisées sur Narbonne et sa périphérie permettent de préciser les différentes phases du développement urbain mais aussi d'attester la présence d'importantes zones portuaires dans les étangs, au sud de la ville. La mise en perspective de ces différentes informations avec celles illustrant les relations commerciales avec son arrière-pays apporte des éléments essentiels pour la compréhension de Narbonne antique

Erythromycin degradation by an esterase in enzymatic membrane reactors

1 Introduction Pharmaceuticals products (PPs) and endocrine disrupting chemicals (EDCs) as well as their transformation products have been detected in almost all effluents from sewage facilities, in surface water, in groundwater, adsorbed on sediments and even in drinking water [1,2]. Ecotoxicity studies have demonstrated that pharmaceutical pollutants could affect the growth, reproduction and behavior of birds, fishes, invertebrates, plants and bacteria [3,4]. Some recently published studies report that the presence of low concentrations of antibiotics in the wastewaters may develop antibiotic resistance in the whole environment [5, 6]. As previously reported by Demarche et al. [7], the use of enzymes might be beneficial to enhance or complement conventional wastewater treatments. As far as enzymes are relatively expensive the reuse of the biocatalyst appears to be essential to ensure the economic and industrial viability of the process. Enzymatic membrane reactors appear to be an interesting alternative since they enable to couple reaction and separation [8]. In fact, in such enzymatic reactors, the substrate is continuously brought in contact with the biocatalyst, which is retained by the membrane, either freely circulating with the retentate or fixed on or within the membrane and the reaction products are recovered in the permeate. This work describes the study of erythromycin degradation by an EreB esterase in free and immobilized forms. It focuses on the comparison between 3 different enzymatic membrane reactors for erythromycin degradation by esterase EreB. In the first configuration the free biocatalyst was confined in the reaction media by a ceramic membrane. In the two other cases, the enzyme was immobilized in the membrane either covalently grafted or adsorbed. Please click Additional Files below to see the full abstract

Identification of QTL with effects on intramuscular fat content and fatty acid composition in a Duroc × Large White cross

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