Abstract
Genome-edited organisms are not only of scientific interest but could also be used for human edible organisms. Myostatin (mstn), which belongs to the transforming growth factor beta superfamily and acts as a negative regulator of skeletal muscle growth, is a main target for improving finfish farming productivity. We previously reported that mstn (Pm-mstn)-deficient juvenile red sea bream (Pagrus major) displayed higher weight gain, specific growth rate, and feed efficiency compared to those of wild type (WT) fish in an 8-week feeding trial using apparent satiation feeding. In this study, to investigate the potential use of the Pm-mstn mutant in aquaculture, we conducted a similar feeding trial at the young stage, close to shipping size, and compared the growth performance and processing yield of the WT and mutant fish as fillets. The mutant fish, with 0.08% less food intake, showed similar growth and an almost 9% higher feed efficiency than those of the WT fish. Moreover, the fillets of the Pm-mstn mutant increased the edible weight by 7%-8% compared to that of the WT. Based on the growth performance and processing yield of the young fish, we concluded that Pm-mstn-deficient red sea bream would be a beneficial breed for future aquaculture.
