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研究了盐度梯度对新吉富罗非鱼(Oreochromis niloticus)受精卵孵化和仔鱼活力的影响。水温(28±0.5)℃下,观察比较了8个梯度的盐度(3‰、6‰、9‰、12‰、15‰、18‰、21‰、24‰)及纯净淡水(盐度为0)条件下,新吉富罗非鱼受精卵的孵化时间、孵化周期、孵化率和畸形率。同时在不同盐度条件下对4批初孵仔鱼进行耐饥饿实验,测定其不投饵存活系数(SAI)值。结果表明,新吉富罗非鱼受精卵在盐度6‰～15‰时,孵化率较高(89.0%～92.7%);盐度低于3‰和高于18‰时,孵化率较低。仔鱼生存适宜盐度3‰～15‰,最适盐度6‰～9‰。新吉富罗非鱼仔鱼在盐度0～3‰及18‰～24‰时,仔鱼的SAI值较低,不适宜仔鱼培育;盐度为6‰～15‰时,仔鱼的活力较高。仔鱼的SAI值与受精卵的孵化率呈正相关关系。
The effects of salinity gradient on egg hatching and larval activity of Oreochromis niloticus were studied. The salinity (3 ‰, 6 ‰, 9 ‰, 12 ‰, 15 ‰, 18 ‰, 21 ‰, 24 ‰) and pure fresh water (salinity 0), the hatching time, incubation period, hatching rate and deformity of the fertilized eggs of the O. tibetanus. At the same time, 4 batches of newly hatched larvae were subjected to the starvation experiment under different salinities to determine their SAI values. The results showed that the hatching rate of fresh tritaus tilapia was higher at the salinity of 6 ‰ to 15 ‰ (89.0% ~ 92.7%), while the salinity was lower at 3 ‰ and higher than 18 ‰. Litter survival suitable salinity 3 ‰ ~ 15 ‰, the optimum salinity 6 ‰ ~ 9 ‰. When the salinity was 0 ~ 3 ‰ and 18 ‰ ~ 24 ‰, the larvae had low SAI value and were not suitable for larval culture. When the salinity was 6 ‰ ~ 15 ‰, larvae had higher vitality. The SAI value of larvae was positively correlated with the hatching rate of fertilized eggs.