Genet. Sel. Evol. 36 (2004) 65-81
DOI: 10.1051/gse:2003051

Genetic analysis of a divergent selection for resistance to Rous sarcomas in chickens

Marie-Hélène Pinard-van der Laan^a, Denis Soubieux^b, Laurence  Mérat^c, Danièle Bouret^d, Gillette Luneau^d, Ginette  Dambrine^b and Pierrick Thoraval<sup>b

a</sup>  UMR Génétique et diversité animales, Institut national de la recherche agronomique, 78352 Jouy-en-Josas Cedex, France
^b  Unité BioAgresseurs, Santé Environnement, Institut national de la recherche agronomique, 37380 Nouzilly, France
^c  Station de pathologie aviaire et parasitologie, Institut national de la recherche agronomique, 37380 Nouzilly, France
^d  Domaine du Magneraud, St-Pierre-d'Amilly, Institut national de la recherche agronomique, BP 52 17700 Surgères, France

(Received 9 December 2002; accepted 27 August 2003)

Abstract
Selection for disease resistance related traits is a tool of choice for evidencing and exploring genetic variability and studying underlying resistance mechanisms. In this framework, chickens originating from a base population, homozygote for the B¹⁹ major histocompatibility complex (MHC) were divergently selected for either progression or regression of tumors induced at 4 weeks of age by a SR-D strain of Rous sarcoma virus (RSV). The first generation of selection was based on a progeny test and subsequent selections were performed on full-sibs. Data of 18 generations including a total of 2010 birds measured were analyzed for the tumor profile index (TPI), a synthetic criterion of resistance derived from recording the volume of the tumors and mortality. Response to selection and heritability of TPI were estimated using a restricted maximum likelihood method with an animal model. Significant progress was shown in both directions: the lines differing significantly for TPI and mortality becoming null in the "regressor" line. Heritability of TPI was estimated as 0.49 0.05 and 0.53 0.06 within the progressor and regressor lines respectively, and 0.46 0.03 when estimated over lines. Preliminary results showed within the progressor line a possible association between one Rfp-Y type and the growth of tumors.

Key words: chicken / selection / resistance / Rous sarcoma / Rfp-Y

Correspondence and reprints: pinard@dga2.jouy.inra.fr

© INRA, EDP Sciences 2004