两种罗非鱼的耐寒性能比较

Comparison of Low Temperature Resistant Performance between Two Tilapia

本文采用人工室内垂直降温模式对尼罗罗非鱼和奥利亚罗非鱼进行不同降温速度的低温胁迫实验,计算出实验鱼的半致死低温与低温胁迫死亡水温范围,计算不同温度下实验鱼的死亡率,得出致死低温范围,讨论持续性低温的伤害。另外,通过双变量Logistic模型拟合降温速度、降温时间和死亡率关系的三维曲面,分别计算2种罗非鱼的冷伤害上限温度(ULCIZ)和半致死伤害积温(SIT)。结果表明,尼罗罗非鱼和奥利亚罗非鱼的ULCIZ分别为15.44℃和15.00℃、SIT分别为-0.0389h·℃和-0.1044h·℃,说明奥利亚罗非鱼群体的耐寒能力较尼罗罗非鱼群体的强,尼罗罗非鱼耐寒性能有待进一步选育提高。

In this study,low-temperature stress experiments on different cooling rates of Nile tilapia and Blue tilapia were carried out with artificial indoor vertical cooling mode.The mortality rates of tilapia in the different temperature and the range of median lethal temperature(LT50)and lethal action temperature of tilapia in the different cooling rate were calculated.Compared with the low temperature resistant performance of different tilapia breeding population;the 3-D surface of relation about cooling rate and mortality were fitted through the vicariate Logistic model,the ULCIZ and SIT of Nile tilapia and Blue tilapia were computed.Test results showed that the ULCIZ of Nile tilapia and Blue tilapia was 15.44℃and 15.00℃,respectively,and the SIT of Nile tilapia and Blue tilapia was-0.038 9 h·℃and-0.104 4 h·℃.In conclusions,the low temperature resistant performance of Blue tilapia was better than Nile tilapia.