Genet. Sel. Evol. 35 (2003) 199-217
DOI: 10.1051/gse:2003004

Genetic parameters for resistance to the Salmonella abortusovis vaccinal strain Rv6 in sheep

Carole R. Moreno^a, Frédéric Lantier^b, Patricia Berthon^b, Anne V. Gautier-Bouchardon^b, Roger Boivin^b, Isabelle Lantier^b, Jean-Claude Brunel^c, Jean-Louis Weisbecker^c, Dominique François^a, Jacques Bouix^a and Jean-Michel Elsen<sup>a

a</sup>  Station d'amélioration génétique des animaux, Institut national de la recherche agronomique, BP 27, 31326 Castanet-Tolosan Cedex, France
^b  Laboratoire de pathologie infectieuse et immunologie, Institut national de la recherche agronomique, BP 1, 37380 Nouzilly, France
^c  Domaine de Bourges-La Sapinière, Institut national de la recherche agronomique, 18390 Osmoy, France

(Received 30 April 2002; accepted 8 October 2002)

Abstract
An experimental population (1216 lambs from 30 sires) of the Inra401 sheep was created in an Inra flock to allow QTL detection for susceptibility to Salmonella infection, wool and carcass traits. The Inra401 is a sheep composite line developed from two breeds: Berrichon du Cher and Romanov. At 113 days of age on average, the lambs were inoculated intravenously with 10⁸ Salmonella abortusovis Rv6 (vaccinal strain). They were slaughtered 10 days after the inoculation. Several traits were measured at inoculation and/or slaughtering to estimate the genetic resistance of the lambs to Salmonella infection: specific IgM and IgG1 antibody titres, body weight loss, spleen and pre-scapular node weights and counts of viable Salmonella persisting in these organs. This paper presents a quantitative analysis of the genetic variability of the traits related to salmonellosis susceptibility. The heritabilities of the traits varied between 0.10 and 0.64 (significantly different from zero). Thus, in sheep as well as in other species, the determinism of resistance to Salmonella infection is under genetic control. Moreover, the correlations between the traits are in agreement with the known immune mechanisms. The genetic variability observed should help QTL detection.

Key words: genetic parameters / Salmonella / sheep / disease resistance

Correspondence and reprints: Carole R. Moreno
    e-mail: moreno@toulouse.inra.fr

© INRA, EDP Sciences 2003