Genetic parameters for first lactation dairy traits in the Alpine and Saanen goat breeds

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Global Analysis of Extracytoplasmic Stress Signaling in Escherichia coli

The Bae, Cpx, Psp, Rcs, and σE pathways constitute the Escherichia coli signaling systems that detect and respond to alterations of the bacterial envelope. Contributions of these systems to stress response have previously been examined individually; however, the possible interconnections between these pathways are unknown. Here we investigate the dynamics between the five stress response pathways by determining the specificities of each system with respect to signal-inducing conditions, and monitoring global transcriptional changes in response to transient overexpression of each of the effectors. Our studies show that different extracytoplasmic stress conditions elicit a combined response of these pathways. Involvement of the five pathways in the various tested stress conditions is explained by our unexpected finding that transcriptional responses induced by the individual systems show little overlap. The extracytoplasmic stress signaling pathways in E. coli thus regulate mainly complementary functions whose discrete contributions are integrated to mount the full adaptive response

MMP19 Is Essential for T Cell Development and T Cell-Mediated Cutaneous Immune Responses

Matrix metalloproteinase-19 (MMP19) affects cell proliferation, adhesion, and migration in vitro but its physiological role in vivo is poorly understood. To determine the function of MMP19, we generated mice deficient for MMP19 by disrupting the catalytic domain of mmp19 gene. Although MMP19-deficient mice do not show overt developmental and morphological abnormalities they display a distinct physiological phenotype. In a model of contact hypersensitivity (CHS) MMP19-deficient mice showed impaired T cell-mediated immune reaction that was characterized by limited influx of inflammatory cells, low proliferation of keratinocytes, and reduced number of activated CD8+ T cells in draining lymph nodes. In the inflamed tissue, the low number of CD8+ T cells in MMP19-deficient mice correlated with low amounts of proinflammatory cytokines, especially lymphotactin and interferon-inducible T cell α chemoattractant (I-TAC). Further analyses showed that T cell populations in the blood of immature, unsensitized mice were diminished and that this alteration originated from an altered maturation of thymocytes. In the thymus, thymocytes exhibited low proliferation rates and the number of CD4+CD8+ double-positive cells was remarkably augmented. Based on the phenotype of MMP19-deficient mice we propose that MMP19 is an important factor in cutaneous immune responses and influences the development of T cells

Étude des possibilités d'allègement du contrôle laitier officiel chez les caprins

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Genetics parameters for first lactation dairy traits in the Alpine and Saanen goat breeds

Genetic parameters for dairy traits in first lactation (milk yield, fat and protein yields, fat and protein contents) were estimated by restricted maximum likelihood in the Alpine and Saanen goat breeds from records including progeny of 473 and 238 unproven bucks respectively, mainly used in natural mating. The differences between breeds could also be estimated when the flocks used both breeds. The sampling of the data sets, the addition of data from 28 and 22 progenies of Al proven sires, and the relationship matrix between sampling sires contributed to increase the connection level between flocks, which, however, remained rather low. In the same environmental conditions, particularly in the same year-flock, the Saanen breed appeared more high-yielding than the Alpine, but solid content was lower. Within-breed, the genetic standard deviation was 1.8-2 fold larger for fat content than for protein content. The heritability of fat and protein yields was rather high (0.31 to 0.39). The genetic correlations between yields were larger than 0.8. They were generally negative but rather low (-0.30 to +0.07) between milk yield and contents. They were clearly positive between fat yield and content (0.45 to 0.59), and between protein yield and content (0.14 to 0.29). They were close to zero and possibly positive between the yield of one component and the content of the other (-0.02 to +0.34). Some discrepancies with the average literature data need to be confirmed.Les paramètres génétiques des caractères laitiers en première lactation (quantité de lait, de matière protéique et de matière grasse, taux butyreux et protéique) sont estimés dans les races caprines Alpine et Saanen par la méthode du maximum de vraisemblance restreint, avec 473 et 238 descendances de mâles non sélectionnés, utilisés principalement en monte naturelle. Les différences entre races sont estimées dans les élevages utilisant les deux types génétiques. Le choix des échantillons, la prise en compte de 28 et 22 descendances de mâles d’insémination sélectionnés ainsi que des parentés entre boucs à l’aide d’un modèle équivalent, contribuent à maximiser les connexions entre élevages qui restent cependant d’un niveau faible. Comparée dans les mêmes élevages, la race Saanen apparaît plus productive que la race Alpine mais son lait est moins riche. Intra race, le taux butyreux est génétiquement 1,8 - 2 fois plus variable que le taux protéique. L’héritabilité estimée des quantités de matière est assez élevée (0,31 - 0,39). Les corrélations génétiques sont supérieures à 0,8 entre quantités. Elles sont généralement négatives mais relativement faibles entre quantité de lait et taux (-0,30 - +0,07). Elles sont nettement positives entre taux butyreux et quantité de matière grasse (0,45 - 0,59) et entre taux et quantité de matière protéique (0, 14 - 0,29). De même, les corrélations croisées entre un taux et la quantité de l’autre matière sont encore positives mais assez variables et plus faibles (-0,02 - +0,34). Certaines différences par rapport aux données de la littérature restent à confirmer

Variability of heat stability of goat milk

Session 09 *INRA Station Génétique des Animaux 31326 Castanet-Tolosan (FRA) Diffusion du document : INRA Station Génétique des Animaux 31326 Castanet-Tolosan (FRA) "Chantier qualité spécifique "Auteurs Externes" département de Génétique animale : uniquement liaison auteur au référentiel HR-Access "International audienc