罗非鱼仔鱼开口率与温度、盐度间模型的建立与优化

采用中心复合设计及响应曲面法研究吉富罗非鱼仔鱼开口率与温度和盐度的量化关系,预实验确定温度范围为20~34℃,盐度为2~10,通过模型优化确定初孵仔鱼从出膜到开口这一阶段最适温度和盐度组合。结果表明,温度对仔鱼的开口率(First feeding rate,FFR)的一次效应有统计学意义(P0.01),盐度对仔鱼开口率的一次效应有统计学意义(P0.05),温度和盐度的交互作用对开口率的影响不具统计学意义(P0.05);温度对仔鱼开口率的二次效应有统计学意义(P0.01);盐度对仔鱼开口率的二次效应有统计学意义(P0.05);温度对开口率的影响较盐度更重要。建立开口率对温度和盐度的二次多项式回归方程,其决定系数为0.986 1,矫正决定系数为0.972 1,预测决定系数为0.911 2,表明所建模型拟合度极高,且可通过温度和盐度预测罗非鱼仔鱼的开口率。对模型方程优化的结果表明,当温度为29℃、盐度为5时,罗非鱼仔鱼的开口率达到最大值87.97%,可靠性达到0.972。

Constructin and Optimizin Model of Relationship Between First Feeding Rate of Larval Tilapia and Temperature and Salinity

Central composite design and response surface method were adopted to study the quantitative relationship between the first feeding rate （FFR, %） of the GIFT strain of Oreochromis niloticus and temperature and salinity . The optimal combination of temperature（20- 34 ℃） and salinity（2- 10） for the fry was determined through the model optimization from newly hatched to the opening of this stage.Results showed that the liner effect of temperature on the first feeding rate （FFR） was highly significant （P 〈 0.01）, and that.of salinity on the FFR was significant （P 〈 0.05）; the interaction effect of temperature and salinity on the FFR was not significant （P 〉 0.05）; quadratic effect of temperature on the FFR was highly significant （P 〈 0.01）, and that of salinity on the FFR was significant （P 〈 0.05）.Temperature has a more significant effect on the FFR than the salinity does. The model equation of the FFR towards temperature and salinity was established, with R2 = 0.9861, adjusted R2= 0.9721 and predictive R2= 0.9112. This showed that the goodness-of-fit of the model was extremely high and it could be used to predict the FFR of newly hatched tilapia larvae.Through optimizing the model equation built, the FFR reached the maximum of 87.97%, with the reliability of 0.972 when the combination of temperature and salinity lay at 29 ℃ and 5, respectively In the industrialized production of tilapia larvae, especially in the early stage from newly hatched tilapia larvae to the first feeding, the production efficiency would be sharpened if the optimal combination of temperature and salinity is applied.