Estimates of heritabilities and genetic correlations of skeletal deformities and uninflated swimbladder in a reared gilthead sea bream (Sparus aurata L.) juvenile population sourced from three broodstocks along the Spanish coasts

Abstract

Lordosis, lack of operculum and failure to inflate the swimbladder constitute a major problem for the gilthead sea bream aquaculture industry. In this study, the effect of the origin of the broodstock on these major anomalies in juvenile sea bream was analyzed. A population of farmed sea bream (n = 909) obtained by industrial mass-spawning from broodstock from three different origins [Cantabrian Sea (CAN), the Atlantic Ocean (ATL) and Mediterranean Sea (MED)] and reared under communal conditions was analyzed from X-ray photograph for skeletal deformities and for uninflated swimbladder. Lordosis and lack of operculum were the most common deformities observed in this study. Juveniles from CAN showed the lowest frequency of skeletal deformities as well as the lowest frequency of uninflated swimbladder. Differences among origins could be partly explained through their different genetic background, but also environmental conditions in the initial facilities and genotype x environment interaction should be considered. A posteriori reconstruction of pedigree was carried out using a microsatellite multiplex (SMsa1) to estimate genetic parameters (heritabilities and genetic correlations) for these traits. Considerable heritabilities were estimated for lordosis [0.53 (0.25–0.77)], lack of operculum [0.37 (0.01–0.81)] and uninflated swimbladder [0.36 (0.12–0.72)] with a positive genetic correlation between uninflated swimbladder and lordosis [0.48 (0.07–0.97)], first reported in this species. All these findings should be relevant for the establishment of successful breeding programs in the aquaculture of this species. Statement of relevance The obtained results provide relevant information to establish a breeding program in gilt head sea bream.