Understanding the Effects of a Tannin Extract on Forage Protein Digestion in the Rumen and Abomasum Using a Dynamic Artificial Digestive System Coupled to a Digestomic Approach

Improving the use efficiency of dietary protein in ruminants is a major challenge to decrease feed supplementation and significantly decrease nitrogen (N) losses to the environment. The aim of this study was to characterize the effects of tannins on protein digestion in the rumen and in conditions simulating the abomasum, using a dynamic in vitro digestive system coupled to a digestomic approach. Three ruminally-cannulated sheep fed with alfalfa hay were infused daily with a solution of tannins, while three other sheep were infused with water (control). Standardized ruminal fluid was introduced into the digester, which simulated the transit of digesta under physicochemical conditions mimicking the abomasum in terms of pH regulation, digestive enzyme infusions and transit rate. Protein degradation in the rumen and in the simulated abomasum was analyzed by determination of fermentation end-products, and identification and quantification of peptides (Label Free Quantification) by LC-MS/MS high resolution (Orbitrap). The analysis of rumen samples showed that tannins result in a clear decrease of fermentation end-products related to protein degradation, namely ammonia (NH3) and iso-volatile fatty acids (VFA), and a greater abundance of the Rubisco, a major plant protein. In the simulated abomasal compartment, the peptidomic analysis showed that the hydrolysis intensity of Rubisco was higher in the presence of tannins compared to the control group. These results indicate that protein-tannin complexes could be dissociated in the physico-chemical conditions of the abomasum, increasing the flow of peptides to the intestine after protection of protein by tannins in the rumen

Deformable model to recover circular generalized cylinders

This paper describes a new approach to recover Circular Generalized Cylinders (CGC) using deformable models . This class includes many objects present on industrial site (pipes) or on the natural environment (human leg, tree trunk) . First, we propose a modeling algorithm of objects with constant cross-section radius, called Uniform Circular Generalized Cylinder s (UCGC). With this assumption, reconstruction is possible from a single view of the object. In the case of a single image, the cross - section radius cannot be estimated . If this radius is unknown, reconstruction is achieved up to a scale factor. The model 3D axis i s parametrized by a B-spline curve . After a coarse initialization, the model changes shape to fit the object contour detected in the studied image. Using different views of the object, the previous approach is adapted to Circular Generalized Cylinders (cross-section radiu s variations are now permitted) . No assumption is made on the axis geometry nor on the way the radius varies . In order to be sufficiently adaptative to the large range of object shape belonging to this class, we propose using two independent B-splin e functions to model respectively axis and cross-section radii variations . These algorithms use the geometrical properties of the occluding contours given by the perspective projection of the objects. It i s the first attempt to solve this problem by taking into account this accurate projective model .Dans cet article, nous proposons une méthode de reconstruction des cylindres généralisés à section circulaire par modèle déformable. Tout d'abord, nous formulons l'hypothèse que les sections de l'objet sont de rayon constant. Nous parlons alors de Cylindres Généralisés Circulaires Uniformes (CGCU). Si le rayon est connu a priori, cette hypothèse permet de retrouver l'axe 3D de l'objet, paramétré par une fonction B-Spline, à partir d'une seule vue, sinon la reconstruction est faite à un facteur d'échelle près. Après une initilisation grossière, le modèle est déformé itérativement jusqu'à ce que sa forme devienne cohérente avec les contours extraits de l'image. Nous montrerons ensuite que l'exploitation de différentes vues d'un même objet permet d'adapter notre approche à la reconstruction de Cylindres Généralisés Circulaires (CGC), objets constitués de sections circulaires à rayon non-constant. Aucune hypothèse a priori n'est faite sur la géométrie de l'axe ou sur la façon dont varie le rayon des sections. Afin de pouvoir s'adapter au plus grand nombre d'objets appartenant à cette classe, deux fonctions B-Spline indépendantes sont utilisées pour paramétrer l'axe et la fonction de variation du rayon

Genetic diversity via REML-BLUP of ex situ conserved macauba [Acrocomia aculeata (Jacq.) Lodd. ex Mart.] ecotypes.

Macauba [Acrocomia aculeata (Jacq.) Lodd. ex Mart.], a palm tree native to Brazil, has a high potential as an alternative source for vegetal oil production. It has several applications in the cosmetics, pharmaceuticals and food industries, and for the production of biofuels. The conservation and characterization of its germplasm are essential for progress in genetic improvement. In this sense, a study of genetic divergence was carried out based on predicted genetic values of 88 accessions form the Active Germplasm Bank of Macauba of EMBRAPA (Brazilian Agricultural Research Corporation). Seven morpho-agronomic characters were observed. The obtained dendrogram generated seven groups. There was a tendency to group accessions according to geographic origin. The graphical dispersion of accession scores plotted in a two-dimensional space showed a pattern correlated to the clusters observed in the dendrogram. The first two principal components (PC1 and PC2) explained 70.4% of the total divergence. The most important traits associated with PC1 and PC2 were the number of fruit bunches and fruit volume, respectively. The application of mixed models in the study of divergence was useful in structuring the germplasm. The structuring of the germplasm is crucial to assist in the choice of parents aiming the selection of recombinant individuals with a superior performance in segregating generations.[On-line first]

Comparison of Muscle Transcriptome between Pigs with Divergent Meat Quality Phenotypes Identifies Genes Related to Muscle Metabolism and Structure

Background: Meat quality depends on physiological processes taking place in muscle tissue, which could involve a large pattern of genes associated with both muscle structural and metabolic features. Understanding the biological phenomena underlying muscle phenotype at slaughter is necessary to uncover meat quality development. Therefore, a muscle transcriptome analysis was undertaken to compare gene expression profiles between two highly contrasted pig breeds, Large White (LW) and Basque (B), reared in two different housing systems themselves influencing meat quality. LW is the most predominant breed used in pig industry, which exhibits standard meat quality attributes. B is an indigenous breed with low lean meat and high fat contents, high meat quality characteristics, and is genetically distant from other European pig breeds. Methodology/Principal Findings: Transcriptome analysis undertaken using a custom 15 K microarray, highlighted 1233 genes differentially expressed between breeds (multiple-test adjusted P-value,0.05), out of which 635 were highly expressed in the B and 598 highly expressed in the LW pigs. No difference in gene expression was found between housing systems. Besides, expression level of 12 differentially expressed genes quantified by real-time RT-PCR validated microarray data. Functional annotation clustering emphasized four main clusters associated to transcriptome breed differences: metabolic processes, skeletal muscle structure and organization, extracellular matrix, lysosome, and proteolysis, thereb

Proteomic analysis of human whole and parotid salivas following stimulation by different tastes

Whole and parotid salivas, collected after stimulation with tastants, were analyzed by 2D electrophoresis and mass spectrometry. In whole saliva, the number of proteins affected by taste stimulation increased in the order sweet < umami < bitter < acid. Annexin A1 and calgranulin A, involved in inflammation, were overrepresented after umami, bitter, and sour stimulations. Their low abundance or absence in parotid saliva after bitter stimulation suggested that they originated from other oral glands or tissues. © 2006 American Chemical Society

A regression-based approach to recover human pose from voxel data

International audienceno abstrac

A 3D shape descriptor for human pose recovery

International audienceno abstrac