The application of microsatellite markers to breeding programmes in the sea bass, Dicentrarchus labrax

Microsatellite markers isolated from a genomic library of sea bass, Dicentrarchus labrax, were used to assess parentage in a breeding programme. The progenies were obtained from a complete factorial design between three males and three females, and mass-reared in a single tank. Three samples of 329, 97 and 360 larvae respectively aged 11, 40 and 116 days-old, were genotyped with microsatellite loci. The parentage of all individuals was determined unambiguously with only two microsatellite loci. A genetic analysis of quantitative characters (survival, body weight, length and malformation, condition coefficient) was realized on the larvae identified in this way. Each of the families appeared significantly different for the analyzed traits. We argue that microsatellites will be a valuable tool in: (i) breed identification (ii) family selection programs in which genetic tagging will allow different genotypes to be reared together, thus greatly reducing the impact of environmental variance and the number of replicate needed ponds.