title: Genomic selection for carrier-state resistance in chicken commercial lines.
abstract: BACKGROUND
  Salmonella propagation by apparently healthy chicken and subsequent food security concerns could be decreased by the selection and use of chicken lines more resistant to carrier-state. In the present study we applied the first steps of the genomic selection methodology to assess the interest of including genetic markers for the genetic evaluation of hen lines infected with Salmonella Enteritidis.
  
  
  METHODS
  We studied commercial laying hen lines divergently selected for resistance to Salmonella carrier-state at two different ages. A total of 600 animals were typed with 1536 SNP markers and artificially infected with S. Enteritidis. Phenotypes were collected four weeks (young animals) or five weeks (adults) later. Two types of variance component analyses, including or not including SNP data, were performed and compared. All variance components were estimated by Bayesian methods and Gibbs sampling.
  
  
  RESULTS
  The comparison of both genetic analyses shows that SNP are efficient in capturing genetic variation, although none of them captures a large affect on the traits studied. Average accuracies do not change between analyses, showing that using SNP data does not really increase information.
  
  
  CONCLUSIONS
  These preliminary results show that genomic selection for Salmonella carrier-state resistance in laying hens is promising, although a denser SNP coverage of the genome on a higher number of animals is needed to assess its feasibility and efficiency compared to classical pedigree evaluation.
authors.affiliation: INRA UMR83 Unité de Recherches Avicoles, 37380 Nouzilly, France. Fanny.Calenge@tours.inra.fr.
authors.forename: Fanny
authors.initials: F
authors.lastname: Calenge
authors.forename: Andres
authors.initials: A
authors.lastname: Legarra
authors.forename: Catherine
authors.initials: C
authors.lastname: Beaumont