不同养殖密度对全雌虹鳟幼鱼生长特性的影响

Effect of growth characteristics of juvenile of all female rainbow trout at different density-attempted in Lhasa

本文以全雌虹鳟(Salmo trutta)为研究对象,通过设置不同养殖密度梯度,对处于幼鱼期的虹鳟进行常规生长指标差异测定,综合分析养殖密度对其生长性能的影响。试验共设置5个养殖密度组,即每个试验槽分别放养400、600、800、1 000、1 200尾,每组3个重复。经过61 d的养殖试验,虹鳟幼鱼体质量从0.35 g长到30.0 g,结果表明:不同养殖密度条件下虹鳟幼鱼的生长指标表现出明显的不同,其中最终体质量、日增重、特定生长率及净增重均随着养殖密度的增大而呈现下降趋势,日均增重由(0.494±0.0025)g下降到(0.427±0.0021)g,降幅明显。在本案例下,1.3827 kg/m^2左右的养殖密度较为合理。

The objective of the study presented was to determine the effects of growth, survival rate and condition factor of juvenile of all female rainbow trout at different density under plateau conditions： Experimental fish were reared at five different stocking densities,d00,600,800, 1 000 and 1 200 individuals per tank. Over the experimental period of 61 days,the results showed that stocking density had insignificant effects on the sur- vival rate and condition factor. The final body,daily weight gain,specific growth rate and net weight gain of fry were decreased with the increase of stocking densities,among those,daily weight gain decreased significantly from（0.494±0.0025 ）g to （0.427±0.0021）g; 1.3827 kg/m2 around the breeding density is more reasonable.