Potential for genomic selection on feed efficiency in gilthead sea bream (Sparus aurata), based on individual feed conversion ratio, carcass and lipid traits

Genetic improvement of feed efficiency is key to improve the economic and environmental sustainability fish farming. However, it requires individual phenotypes efficiency, which are difficult if not impossible obtain when reared in tanks or cages. Here, we applied validated on gilthead sea bream a method evaluate based rearing aquariums under restricted feeding. We collected 538 (average weight = 54.50 g). Based these phenotypes, 174.6 g) were groups divergent (high low efficiency), validating that had an impact group at later stage. All fish, their parents as well 794 sibs cages production environment, genotyped 57k SNP array estimate genomic heritability correlations between traits. showed was heritable but did find significant associated QTLs. also negatively genetically correlated viscera yield, indicating most efficient less than least ones. Altogether, results support measuring feeding may be used reliable phenotyping despite bias intrinsically linked rearing.