摘要
研究五日龄草鱼对水温的突变（升高或降低）、渐变（升高或降低，速度约３℃／ｈ）、渐降后又回升的耐受性，以及低温对其摄食和冷休克的影响。结果表明：鱼的驯化温度为２２℃时，温度突然升高和逐渐升高引起的致死高温分别为３５．６℃和３６．５℃，而驯化温度为２５℃的鱼，这两者分别为３７．３℃和３７．４℃；对这两批驯化温度不同的鱼，无论哪种变温方式，水温上升１０～１３℃或降低１２℃引起的死亡率都不到１０％；对于驯化温度为２２℃的鱼，水温渐降至７℃，维持１２ｈ，然后回升至室温后２４ｈ内的死亡、昏迷及畸形鱼总百分比不到１０％；五日龄草鱼开始摄食水温为１１．０℃，０、５０％、１００％冷休克水温分别为１３．５、１０．７、８．０℃。
The results of a study on the tolerance of 5dayold grass carp toward the sudden change (rise of fall), gradual change (rise or fall, at speed of about 3℃/h) and fallthenrise of water temperature showed that with the acclimation temperature (AT) being 22℃, its upper lethal temperatures caused by sudden and gradual rise of water temperature were 35.6℃ and 36.5℃, while with AT being 25℃, they were 37.3℃ and 37.4℃, respectively. When water temperature rose by 10~13℃ or fell by 12℃ suddenly or gradually, their mortality was below 10%. When water temperature gradually fell to 7℃, stayed for 12 hours at 7℃ and rose back to room temperature (22℃) 24 hours later, the total percentage of the dead, comatose and deformed fish was below 10%. The temperature at which the 5dayold grass carp began feeding was 11℃, and the temperatures at which 0, 50%, and 100% larvae got cold shock were 13.5, 10.7, and 8.0℃, respectively.
关键词
五日龄草鱼
水温突变
水温渐变
死亡率
草鱼
5dayold grass carp
sudden change of water temperature
gradual change of water temperature
mortality
