Heritability of susceptibility to Salmonella enteritidis infection in fowls and test of the role of the chromosome carrying the NRAMP1 gene

373 thirteen-week-old chicks issued from a commercial cross and 312 chickens from the L2 line were intravenously inoculated with 106 Salmonella enteritidis and the numbers of Salmonella in the spleen, liver and genital organs were assessed 3 days later. Heritabilities of the number of Salmonella were estimated at 0.02 ± 0.04 and 0.05 ± 0.05 in the liver; at 0.29 ± 0.07 and 0.10 ± 0.06 in the spleen; and at 0.16 ± 0.05 and 0.11 ± 0.08 in the genital organs, in the first and second experiments, respectively. The difference between the two experiments could result from sampling variations and from differences in the genetic structure of the two populations possibly including both heterosis and additive effects as well as their interaction in the first experiment. Genetic correlations between the number of bacteria in the genital organs and liver (0.56 ± 0.58 and 0.76 ± 0.32 in the first and second experiments, respectively) and spleen (0.37 ± 0.24 and 0.79 ± 0.23) were positive. Moreover a significant within-sire effect of VIL1, a marker gene for NRAMP1, was observed in 117 progeny resulting from 25 informative matings. These results indicate that there are genetic differences in the resistance to visceral infection by S. enteritidis in these commercial egg-laying flocks, and suggest that these differences are at least partly due to genetic polymorphism in the NRAMP1 region

Cytogenetical anchoring of sheep linkage map and syntenic groups using a sheep BAC library

In order to simultaneously integrate linkage and syntenic groups to the ovine chromosomal map, a sheep bacterial artificial chromosome (BAC) library was screened with previously assigned microsatellites using a sheep-hamster hybrid panel and genetic linkage. Thirty-three BACs were obtained, fluorescently labelled and hybridised on sheep-goat hybrid metaphases (2n = 57). This study allowed us, (i), to anchor all linkage groups on sheep chromosomes, (ii), to give information on the probable position of the centromere on the linkage map for the centromeric chromosomes, (iii), to contradict the previous orientation of the ovine × linkage group by the mapping of BMS1008 on OARXq38. Concerning our somatic cell hybrid panel, this study resulted in the assignment of all the previously unassigned groups to ovine chromosomes and a complete characterisation of the hybrid panel. In addition, since hybridisations were performed on a sheep-goat hybrid, new marker/anchoring points were added to the caprine cytogenetic map

Rapid Typing of Transmissible Spongiform Encephalopathy Strains with Differential ELISA

A strain-typing ELISA distinguishes bovine spongiform encephalopathy from other scrapie strains in small ruminants

Animal models of emerging diseases: An essential prerequisite for research and development of control measures

International audienceInfectious diseases represent a life-threatening menace for human and animal populations. The emergence of new diseases from animal reservoirs, as well as the re-emergence of “old” diseases, requires well-adapted responses from the scientific community to provide accurate data for controlling the pathogen dissemination and its consequences. In this article, we will review the use of animal models as tools for our understanding of the physiopathology of emerging or re-emerging infectious diseases and possibilities of diagnosing them, the evolution of pathogens virulence and host spectrum, and the definition of vaccine or therapeutic targets and the testing of their biosafety and efficiency. We will illustrate these achievements through various examples from the literature and from the experience of coordinating the European infrastructure project NADIR, the Network for Animal Disease and Infectiology Research for European animal facilities

Better defences for animal and human health

International audienc

Présentation du projet IMOPA"Imagerie Optique du Petit Animal"

National audienc

Imagerie fonctionnelle et interventionnelle appliquées à la détermination des mécanismes cellulaires conduisant au portage de <em>Salmonella</em> chez le poussin

National audienc