不同养殖密度对大鳞鲃生长性能的影响
Effects of Different Stocking Densities on Growth Performance of Barbus capito

为探究养殖密度对大鳞鲃幼鱼生长性能的影响，本试验设置4.83 g/L (低密度)、6.00 g/L (中密度)、7.21 g/L (高密度) 3个密度梯度，开展为期30 d室内养殖试验，测定各组大鳞鲃存活率、体长、体重、相对增重率、特定生长率、日均摄食率、饵料系数及肥满度等指标。结果显示：养殖密度升高会产生拥挤胁迫，显著抑制大鳞鲃摄食与生长；仅高密度组出现1尾死亡，三组成活率无显著差异(P > 0.05)；末均重、相对增重率、特定生长率、日均摄食率随密度升高显著降低，饵料系数显著上升(P < 0.05)；低密度组肥满度显著低于中、高密度组(P < 0.05)，中高密度组间无显著差异。综合生长、摄食与饲料利用效率，4.83 g/L低密度条件下大鳞鲃生长性能与饵料转化效果最优；中密度可兼顾水体产出，高密度会明显降低养殖效益。本研究可为大鳞鲃鱼种标准化集约化培育提供密度参考依据。
To investigate the effects of stocking density on the growth performance of juvenile Barbus capito, a 30-day indoor breeding experiment was carried out with three density gradients: low density (4.83 g/L), medium density (6.00 g/L) and high density (7.21 g/L). Indicators including survival rate, body length, body weight, weight gain rate, specific growth rate, daily feeding ratio, feed conversion ratio and condition factor of Barbus capito in each group were measured. The results showed that increased stocking density caused crowding stress and significantly inhibited feeding and growth of Barbus capito. Only one individual died in the high-density group, and there was no significant difference in survival rate among the three groups (P > 0.05). The final average body weight, weight gain rate, specific growth rate and daily feeding ratio decreased significantly with the increase of density, while the feed conversion ratio increased significantly (P < 0.05). The condition factor of the low-density group was significantly lower than that of the medium and high-density groups (P < 0.05), while no significant difference existed between medium and high-density groups. Comprehensive analysis of growth, feeding and feed utilization efficiency indicated that Barbus capito reared at low density of 4.83 g/L achieved the optimal growth performance and feed conversion efficiency. Medium density balanced water output, whereas high density remarkably reduced breeding economic benefits. This study provides a theoretical reference for standardized intensive fry culture of Barbus capito.