선발과 비선발 참돔 (Pagrus major) 계통의 성장 양상 비교

Abstract

Growth performances of the selected and the non-selected red sea bream (Pagrus major) lines were evaluated up to marketable size. The offspring were mass-produced either from the selected line (the fourth generation of broods from mass selection) or the non-selected line (the second generation of wild broods). Early (59 to 103days old, trial I) and late growth performances (4 to 24months old, trial II) were evaluated based on communal rearing in land-based tanks and sea cages, respectively. In trial I, the selected line exhibited significantly higher values in both weight gain (WG) and specific growth rate (SGR) when compared to those observed in the non-selected line (P<0.05). In trial II comprising of three growth phases (4-9, 9-16 and 16-24months old), selected line showed only slightly improved in WG and SGR at the beginning two growth phases (4-9 and 9-16months old) (P>0.05), however, displayed significantly higher values at the last growth phase (16-24months old) (P<0.05). Overall WG and SGR throughout the experiment (4-24months) were also significantly higher in the selected line than the non-selected line (P<0.05). Consequently, mean body weight of the selected line at 24months old was 1.4-fold (40.8% increased) as compared to that of the non-selected line. This present result indicates that mass selection of this species against the growth traits might be quite effective, and the present advance has important implication in the productivity enhancement of red sea bream aquaculture.