Genetic parameters for shell growth and survival in Portuguese oyster (Crassostrea angulata) larvae, juveniles, and adults

The Portuguese oyster, Crassostrea angulata, is an important aquaculture bivalve species in Asia, where it is native. This study was carried out to estimate genetic parameters for shell growth and survival over six generations of selection based on harvest whole weight. The phenotypic measurements including shell height and length, and survival rate at days 5, 25, and 150 were collected from the fourth to sixth generations. A linear mixed model was used to estimate heritability and genetic correlations at days 5, 25, and 150 after fertilization. Heritability estimates for shell height and length were high at three studied times, ranging from 0.27 to 0.76. Heritability estimates for survival (h² = 0.23–0.26) were lower than those found for shell growth traits and estimates of genetic correlations between survival and shell growth traits at the three studied ages were low (range − 0.056–0.189) and did not differ significantly from zero, suggesting that an index could be developed to improve two traits simultaneously.