淡水养殖大黄鱼技术初探

Techniques on Large Yellow Croaker Culture in Freshwater

对大黄鱼进行淡化养殖,首先将23日龄的大黄鱼苗种,从自然海水盐度28.46直接降至8.00,然后以2.00/d降盐幅度,再将盐度降至4.00,紧接着以1.00/d降盐幅度,继续将盐度降至2.00,最后以0.50/d的降盐幅度,将盐度降至0,经过4个月的纯淡水养殖,成活率为(59.02±6.01)%,显著高于其他的驯化方式(P<0.01);水温为23~29℃,淡水养殖成活率[(59.02±6.01)%^(90.74±1.09)%]显著高于海水养殖对照组的成活率[(30.33±6.17)%^(55.32±6.66)%](P<0.01);淡水养殖大黄鱼全长、体长和体质量特定生长率均值分别为(0.59±0.16)%/d、(0.70±0.22)%/d和(2.26±0.94)%/d,分别比海水养殖对照组高78.79%、52.17%和68.66%。

Juvenile large yellow croaker（Larimichthys crocea）was acclimatized and cultured in freshwater for 4months.The 23 day old large yellow croaker was directly acclimatized from seawater at a salinity of28.46 to 8.00,to a salinity of 4.00,then to a salinity of 2.00 at a rate of 1.00/d,and finally to freshwater by 0.50/d.The survival rate was found to be（59.02±6.01）%,very significantly higher than that in the other acclimatization patterns（P〈0.01）.There was very significantly higher survival rate [（59.02±6.01）—（90.74±1.09）]% at water temperature of 23—29 ℃in freshwater aquaculture than that in the control group in the seawater[（30.33±6.17）—（55.32±6.66）]%（P〈0.01）.The large yellow croaker farmed in the freshwater had 78.79% higher total length（0.59±0.16）%/d,52.17% higher body length（0.70±0.22）%/d,and 68.66% higher mean specific growth rate in body weight（2.26±0.94）%/d than those in the control group in the seawater.