流速、温度对西伯利亚鲟幼鱼生长的影响

在90 d的饲养实验中，研究了集约化室内储水池养殖条件下，流速和温度对西伯利亚鲟幼鱼生长的影响。按照流速，实验鱼分为4组：即流速分别为 V1组(0.12 m·s-1)，V2组(0.16 m·s-1)， V3组(0.20 m·s-1)，和V4组（0.5 h流速为 0.20 m·s-1, 0.5 h流速为 0 的间隙式水流组）。水温在13.8 ～24.7 ℃变化。 在16.7～22.5 ℃的温度段内，随着流速增大，幼鱼的最终体重、体长、生长效率、净增重、每日生长率及日增重等指标均逐渐增大，饵料系数逐渐降低，其中西伯利亚鲟鱼的生长效率(GE)与流速(V)之间存在显著正相关性，其关系式为GE＝52.5 V + 69.567 (R2 = 0.997, P< 0.05)。尽管高流速V3组的特殊生长率(DGR)是最大的，但V3组在22.5～4.7 ℃之间和13.8～16.7 ℃之间时DGR是最小的。间隙式水流V4组(0.5 h流速为0.20 m·s-1，0.5 h流速为0)DGR和净增重(NY)不是最高，但其饵料系数(FC)和生长效率(GE)分别是各组中最低和最高的，而且在高温和低温段DGR均有比其他组升高的趋势。另外，水流因子与温度交互作用影响西伯利亚鲟幼鱼的生长，本次四组流速组西伯利亚鲟幼鱼的最适生长水温各不相同，在20.2～20.7 ℃之间。结果显示在设施集约化养殖中，V4组能够产生较好的效益。图2表2参22 关键词：西伯利亚鲟； 生长； 集约化养殖； 流速； 温度

Effect of water current and temperature on growth of juvenile Acipenser baeri

Effect of water current and temperature on growth of juvenile sturgeon Acipenser baeri in intensive indoor (semi-recirculating) tank culture was investigated in a 90-day rearing trial. Fish were reared in continuous water current with three levels of velocity of 0.12(V1), 0.16(V2) and 0.20 m·s-1(V3) respectively, and isochronic water current (in half an hour with a velocity of 0.20 m·s-1, then in the next half an hour of intermission with a velocity of 0 m·s-1)(V4), under water temperature varying between 13.8 ℃ and 24.7 ℃. Within a range of water temperature of 16.7 - 22.5 ℃, growth efficiency (GE) and daily growth rate (DGR) increased with the increase of velocity of water current, and maximum DGR occurred in V3 group. There was significant positive linear relation between GE and V: GE＝52.5 V + 69.567 (R2 = 0.997, P＜ 0.05), when the velocity of water current ranged from 0.12 m·s-1 to 0.20 m·s-1. In contrast, within a range of water temperature of 13.8 - 16.7 ℃ or 22.5 - 24.7 ℃, DGR of V3 group were lower than that of V1 and V2 groups. Fish in the group with intermission of non-water current obtained the highest GE while lowest FCR at a water temperature of 20.7 ℃. It suggested that water current and water temperature have reciprocal effect on the growth of juvenile sturgeon A. baeri. The fish has different optimal water temperatures at different velocity of water currents, and the optimum temperatures are between 20.2 ℃ and 20.7 ℃.This result suggests that group V4 is the best among these groups that can produce better economic benefits.