The pigmentation of a new backcross sea bream (RF1), red sea bream Pagrus major (RSB) ♀ x F1 (RSB ♀ x crimson sea bream Evynnis japonica ♂) ♂, weighing 265 g on an initial mean body weight, was compared with RSB, weighing 280 g on an initial mean body weight, by a 30-day-feeding trial. The FI were initially bred as a new hybrid, owing to the improvement of dark cultured-RSB pigmentation with
... [Show full abstract] crimson red sea bream in early 1970s. On day 15 of the feeding trial, integument carotenoid and astaxanthin contents of RF1 fed a diet with 3.0 mg astaxanthin (AS) /100 g diet were significantly higher than RSB and/or RF1 fed other diets with O and 1.5 mg AS/100 g diet. The integument carotenoid and AS contents of RF1 and RSB rose with an increase in dietary AS amounts on the final day of the feeding trial. Moreover, the contents of RF1 tended to be higher than RSB at each dietary AS treatment. These indicate that RF1 have a preferential trait that is effectively pigmented by a shorter rearing duration with a lower AS intake than RSB.
