Create new fish and develop novel systems for aquaculture

我们的目标是开发不利用动物蛋白源就能生长良好的养殖鱼类品种，以及适合这些品种的闭式循环水产养殖系统(CRASS)，利用植物油作为脂源进行海水鱼类养殖具有潜在的前景。我们发现，以回收的食物垃圾作为鱼粉的部分替代饲料的鱼的磷(P)排放负荷降低，以及当它们在饲料中添加鱼粉时，对海水鱼来说牛磺酸的必要性。我们成功地将幼鱼完全培育成了成鱼。考虑到需要减少营养物质排放负荷的物种，特别是那些适合粗糙鱼的物种，我们测定了我们生产的‘全鱼’GH转基因罗非鱼(GHTi)在饱食条件下的N和P排放负荷，并就其生长特性进行了研究。GHTI的生产效率更高，表现为比生长率高3倍，饲料效率高，蛋白质存留率高。此外，GHTI的总氮(N)和磷(P)排放负荷低于对照鱼。同时，GHTI对钙、磷的需要量也较高，成功地培育出从仔鱼到市场规格的最佳成鱼具有重要意义。有必要通过进行选择最佳物种的实验，以及用新的饲料饲养高附加值的淡水和海水鱼类物种来产生实际应用。

We are aiming to develop the farmed fish species that can grow well without utilization of animal protein source, and the optimal closed recirculating aquaculture systems(CRASs) for these species.We had a likely prospect for culture of marine fish by utilizing vegetable oil as lipid source. And we found that lowered phosphorus(P) discharge loads from the fish fed on diets with recycled food waste as a partial replacement as fishmeal, as well as the necessary of taurine for marine fish when they fed on diets with fishmeal reduced. We succeeded in cultivating larval fish up to adult fish completely in a CRASs. Given the need for species with reduced nutrient discharge loading, in particular those suitable for CRASs, we determined the N and P discharge load from the' all-fish' GH-transgenic tilapia(GHTi) of our produced line under satiation feeding with respect to its growth characteristics. The greater efficiency of productivity of GHTi was reflected in a 3 times higher specific growth rate, higher feed efficiency and protein retention when fed less diet. Moreover, the total nitrogen(N) and phosphorus(P) discharge loads from GHTi were lower than those of the control fish. Meanwhile, GHTi seemed to have a higher requirement of calcium and phosphorous.It is meaningful to succeed in cultivating the optimal fish from larvae up to market-size adults in a CRASs. It is necessary to yield practical applications by conducting experiments of selecting optimal species, as well as rearing high-value-add species of freshwater and marine fish with novel diets.