海水温度对金鲳鱼保活过程中应激和代谢的影响

Effect of Temperature on Stress and Metabolism of Golden Pompano during Keep-alive Transportation

目的低温休眠是鱼类保活运输中的关键技术之一,以金鲳鱼为对象,探讨海水温度对其保活过程中应激和代谢的影响,确定保活运输的重要温度参数。方法对鱼体进行梯度降温使之休眠,在不同温度下进行保活,得出最佳保活温度,对保活过程中的各项指标进行测定。结果在金鲳鱼保活过程中,鱼体代谢会使水体中氨氮总含量和pH值上升;金鲳鱼受低温胁迫会产生应激反应,血清的皮质醇含量上升,血糖含量下降,尿素氮和总胆固醇含量上升,乳酸脱氢酶活性稍有升高,谷草转氨酶活性显著升高,肌肉中糖原含量下降,乳酸含量上升;将金鲳鱼在(25±2)℃下暂养6 h后,梯度降温至13~14℃时金鲳鱼逐渐进入休眠状态,然后再移入15~17℃海水中进行保活;在15℃和17℃保活36 h存活率均为100%,保活48 h存活率分别为83%和75%。结论海水温度对金鲳鱼保活过程中应激和代谢具有重要影响,且为金鲳鱼的有水保活运输提供了理论指导和关键温度参数。

Low temperature dormancy is one of the key technologies in fish keep-alive transportation.The influences of seawater temperature on the stress and metabolism of golden pompano(Trachinotus ovatus)were studied in the process of keep-alive transportation,to obtain the important temperature parameters for keep-alive transportation.Gradient cool-ing of the fish body was implemented to make it dormant,keep the fish alive at different temperatures,obtain the best keep-alive temperature,and measure various indicators in the keep-alive process.The results showed that the fish meta-bolism increased the total ammonia nitrogen content and pH value in seawater in the process of keep-alive transportation.Golden pompano had a stress response under low temperature:the cortisol content in serum increased,the blood sugar content decreased,the urea nitrogen and total cholesterol content increased,lactate dehydrogenase activity increased slightly,and aspartate aminotransferase activity increased significantly;the glycogen content in muscle decreased,and lactic acid content increased.Golden pompano was kept temporarily at(25±2)℃for 6 h,and the temperature was gradu-ally lowered to 13-14℃,at this time,the fish was in a dormant state.Then the fish was moved to seawater of 15-17℃to keep alive.The survival rates at 15℃and 17℃for 36 h were both 100%,and the survival rates for 48 h were 83%and 75%respectively.The results showed that seawater temperature has an important influence on the stress and meta-bolism of golden pompano.We can get theoretical guidance and key temperature parameters for the keep-alive transporta-tion of golden pompano.