Reduction of albinism in juvenile flounder Paralichthys olivaceus hatchery-reared on fertilized eggs of red sea bream Pagrus major , and its critical stage for the effective feeding

The critical and effective stage of feeding to reduce albinism was investigated by changing the initial feeding time of fertilized eggs to flounder (Paralichthys olivaceus ) larvae. The effective period for feeding of eggs was D-stage (7 mm in T.L.) to F-stage (10 mm). Larval flounder at the small size of nearly 8 mm preferred newly hatched larvae with yolk sac of red sea bream (Pagrus major ) to the eggs, and began to feed on the eggs at size of 8.5-9.0 mm. The critical stage determining the appearance of albinism in hatchery-reared juvenile flounder was estimated to be the initial stage of metamorphosis, i.e. early D-Stage (8.0-8.5 mm). One to two g (2-4 x 10 super(3)) is enough for daily amount of feeding per 10 super(3) larvae.