| Verasper moseri Jordan et Gilbert, belong to Pleuronectitormes, Pleuronectidae, Verasper.Distributed in Okhotsk Sea, Yellow Sea, Bohai Sea Japan northwest sea, Korea southwest sea. Verasper moseri meat quality is exquisite, flavour is delicious, grow quickly, both may carry out interior cultivation and, may in the pond, cage culture. In present, entire consumption market demand looks well, easy to accept by our country saltwater aquaculture person, It will be become the fish leading. will grow seedlings reaching a technology studying up to gigantic push effect, It is very important to our country fishery structural adjustment and the seawater fish breeding and poultry raising stabilizes developing.Barfin flounder, Verasper moseri Jordan et Gilbert, are large flatfish inhabiting cold seawater basins in the northwest Pacific, especially Hokkaido of Japan. The techniques of barfin flounder aquaculture and breeding which based on Chinese condition were studied step by step since 2001. By reinforced culture of those well-chosen parent fish, an ideal ovulation result was obtained. The barfin flounder seedling which were brought from Japan, was grew up into sexual maturation and reproduction after 3-years culture in the conditions such as:water temperature range 10℃～21℃, light intensity 500lx～1200lx, salinity 25～32, pH7.6～8.2, DO≥5mg/L, and reared the formulated feed. The spawners'gonad developed to theⅣstage by indoor culturing, nutrition enriching, water-temperature and photothermal control. After duplicate hormone implants, stable harvest of a number of eggs with good quality can be obtained. Conjectured the effective time of hormone inducement is 5d～20d. The curve of eggs collection number in 5d-24d after the second hormone inducement was similar as the parabola and the peak is the 13d (1800ml/d). The whole reproduction season could last for 70d-80d. The study demonstrated the optimum water temperature range for egg collection was 6℃～11℃. Used 175 barfin flounder spawners,2.591×107 eggs(floating eggs 1.852×107 thereunto) were been obtained in 2007. The total fertilization rate was 71.48%.Barfin flounder, Verasper moseri Jordan et Gilbert, a large flatfish in the northwest Pacific, ranges from Sea of Okhotsk, Russia to Yellow Sea, China. The most resourceful area of barfin flounder is the area around Hokkaido of Japan at present. There were barfin flounder distributing in Bohai sea and Yellow Sea, but the species nearly died out in such areas during the last 40 years. Barfin flounder was introduced into China as a cold water flatfish which is suitable for aquaculture and resource enhancement in 2001-2004. Has been cultivated to spawners, the barfin flounder were induced ovulation using water-temperature control, photothermal control and hormone implants. Nearly 200 of 500 female fish's gonads developed well and the eggs matured successfully.2.591×107 eggs were obtained, floating eggs were 1.852×107 and total fertilization rate was 71.48%. Embryos were incubated in sea water (salinity 32～33) at 9℃～10℃. The larvae hatched out in about 144h-156h after fertilization. The optimum temperature range and salinity range for hatch were ascertained. The condition for seedling rearing:①Hatching larvae:water temoerature 13℃, salinity 33～35, no water exchange, light density 400lx～600lx.②35d larvae: 17℃, salinity 28～30, water exchange rate per day 100%, light density 500lx～800lx.③juvenile and young fish srtage:16℃～17℃, salinity 28～30, light density 800lx～12001x. In the toaal rearing period, several water enivorment conditions were such as: pH7.8～8.2, DO≥6mg/L, NH4+-N≤0.1mg/L. The feeding scheme was Chlorella, rotifer, artemia salina, artemia, and artificial microdiet formulated feed.6.00×106 newly hatching larvae were obtained in 2007, and the hatch rate was 32.42%. 1.27×106 seedling (total length 35mm～50mm) were obtained, seedling rate was 21.14%. This was the first record in China and international on large-scale (magnitude up to millions of level) seedling rearing of barfin flounder.Barfin flounder, Verasper moseri Jordan et Gilbert (マツカワin Japanese), are large flatfish inhabiting cold seawater basins in the northwest Pacific, especially Hokkaido of Japan. The species is suitable for aquaculture and resource enhancement due to its high commercial value and growth rate in low water temperature. In this paper, the technology of seedling and spawner culture condition indoor, reproduction of regulation-control, hormone implants inducement, ovulation and artificial fertilization, hatching and seedling rearing were described in detail. The barfin flounder seedling (average total length:83mm, wet weight:10g～11g) which was brought from Japan in December 2003, was grew up into sexual maturation and reproduction after 3-years culture in the conditions such as:water temperature range 10℃～21℃, light intensity 500lx～1200lx, salinity 25～32, pH7.6～8.2, DO≥5mg/L, and reared the formulated feed. By reinforced culture of those well-chosen parent fish, an ideal ovulation result was obtained. The spawners'gonad developed to the IV stage by indoor culturing, nutrition enriching, water-temperature and photothermal control. The whole reproduction season could last for 70d-80d. Used 175 barfin flounder spawners,2.591×107 eggs(floating eggs 1.852×107 thereunto) and 6.00×106 newly hatching juveniles were been obtained in 2007. The total fertilization rate and total hatching rate were 71.48%. Embryos were incubated in sea water (salinity 32～33) at 9℃～10℃. The larvae hatched out in about 144h-156h after fertilization. The optimum temperature range and salinity range for hatch were 10℃～12℃and 33～35, respectively. The condition for seedling rearing:①Hatching larvae:water temoerature 13℃, salinity 33～35, no water exchange, light density 400lx～600lx.②35d larvae:17℃, salinity 28～30, water exchange rate per day 100%, light density 500lx～800lx.③juvenile and young fish srtage:16℃～17℃, salinity 28～30, light density 800lx～1200lx. In the toaal rearing period, several water enivorment conditions were such as:pH7.8～8.2, DO>6mg/L, NH4+-N≤0.1mg/L. The feeding scheme was Chlorella, rotifer, artemia salina, artemia, and artificial microdiet formulated feed.6.00×106 newly hatching larvae were obtained in 2007, and the hatch rate was 32.42%.1.27×106 seedling (total length 35mm～50mm) were obtained, seedling rate was 21.14%.
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