不同盐度下萨罗罗非鱼、尼罗罗非鱼和以色列红罗非鱼耗氧率、临界溶氧和窒息点的比较分析

在水温(28.5±0.5)℃,pH值7.8~8.65条件下,设置了0、10、20和30等4种盐度,测定了萨罗罗非鱼(Sarotherodon melanotheron)、尼罗罗非鱼(Oreochromis niloticus)和以色列红罗非鱼(Israel red tilapia)的耗氧率、临界溶氧量、窒息点及抵达临界溶氧量和窒息点时间.实验结果表明:除了在盐度为20时,以色列红罗非鱼耗氧率最低,萨罗罗非鱼次之外,在其他盐度都是尼罗罗非鱼耗氧率最高,以色列红罗非鱼次之,萨罗罗非鱼最低.尼罗罗非鱼和以色列红罗非鱼临界溶氧量、窒息点都随盐度的增加而增加,盐度为30时最高,盐度为0时最低,而且以色列红罗非鱼始终都高于尼罗罗非鱼.萨罗罗非鱼是在盐度为20时最低,在盐度为10时最高.3种罗非鱼都是在盐度为20时,抵达临界溶氧量和窒息点的时间最慢,在盐度为30时抵达临界溶氧量和窒息点的时间最快.

At Different Salinities,Compared Analysis on Rate of Oxygen Consumption,Critical Oxygen,Point of Asphyxiatio to Blackchin Tilapia,Nile Tilapia and Israel Red Tilapia

At the water temperature(28.5±0.5) ℃ and pH(7.8~8.65),rate of oxygen consumption,critical oxygen,point of asphyxiatio,time to critical oxygen and time to asphyxiation of Black tilapia,Nile tilapia and Israel red tilapia which were bred at different salinity 0,10,20 and 30 were determinated.The result indicates that,at 0,10 and 30 salinity,the rate of oxygen consumption of Nile tilapia is the highest among three species,and Blackchin tilapia ' s is the lowest.But at 20 salinity,the rate of oxygen consumption of Israel red tilapia is lower than blackin tilapia's.The critical oxygen and point of asphyxiatio of Nile tilapia and Israel red tilapia increased with the rising of water salinity,and its salinity is the highest at 30 salinity,and the lowest at 0 salinity,the critical oxygen and point of asphyxiatio of Nile tilapia are lower than Israel red tilapia's all the time.The critical oxygen and point of asphyxiatio of blackchin tilapia are the highest at 10 salinity,and its salinity is the lowest at 20 salinity.The time to critical oxygen and the time to point of asphyxiatio are slowest at 20 salinity to three tilapias,and its salinity are the quickest at 30 salinity.