温度和盐度对吉富品系尼罗罗非鱼受精率和孵化率的联合影响

Combined effect of temperature and salinity on the fertilization and hatching rate in the GIFT strain of Nile tilapia,Oreochromis niloticus

采用中心复合设计和响应曲面方法研究了温度（T,℃）和盐度（S）对吉富品系尼罗罗非鱼人工受精率（FR,%）和孵化率（HR,%）的综合影响。设定的温度范围为20~34℃,盐度范围为0~18。建立了温度、盐度与受精和孵化之间关系的定量模型,并通过分析明确了温度与盐度的最优组合。结果表明,吉富罗非鱼在温度与盐度较高或较低范围内受精率与孵化率都处于较低水平。温度和盐度的一次与二次效应对受精与孵化均有极显著的影响（P〈0.01）。温度与盐度二者间协同效应不显著（P〉0.05）。建立了吉富罗非鱼受精率与孵化率的多项式方程,复相关系数分别达到了0.957 8和0.960 1（P〈0.01）,可以用于预测吉富罗非鱼的受精率和孵化率。利用统计优化技术明确,在温度27.14℃,盐度8.95时,罗非鱼最佳的受精率为80.81%,孵化率为77.63%。本研究旨在考察温度与盐度同时变化对吉富罗非鱼受精率与孵化率的影响,探讨最佳温度-盐度组合以增加吉富罗非鱼苗种产量。

We evaluated the effect of temperature and salinity on the artificial fertilization rate（FR,%） and hatch-ing rate（HR,%） in the GIFT strain of Oreochromis niloticus using a Central Composite Design and Response Surface method.The fish were reared in temperatures ranging from 20？34？C and the salinities ranging from 0？18.Both FR and HR decreased as temperature and salinity approached the lower and higher bounds.HR and FR were significantly affected by the linear and quadratic of temperature and salinity（P0.001）.However,there was no evidence for a synergistic effect between temperature and salinity（P0.05）.After correcting for the negative cor-relation coefficient,the r2 values for the equations explaining temperature and salinity were 0.957 8 and 0.960 1,respectively（P0.01）.Thus,these models can be used to forecast HR and FR in Nile tilapia.The highest FR（80.81%） and HR（77.63%） were observed eggs incubated at 27.14？C and 8.95 of salinity.Our results may be used to improve fertilization and hatching success in cultured strains of Nile tilapia.