丝足鱼(Trichogaster trichopterus)耐盐性及盐度驯化

以斑马鱼（Danio rerio）和剑尾鱼（Xiphophorus helleri）作比较，对丝足鱼（Trichogaster trichopterus）耐盐性进行研究，测定丝足鱼的96h半致死盐度（LS50-96h）、平均存活时间（MST）、50％存活时间（MT50）、开始死亡时间和死亡率等耐盐指标，并逐级提高养殖水体盐度对丝足鱼进行耐盐驯化实验，测定丝足鱼在盐度为14水体中不同驯化时间的血清渗透压。结果表明，①丝足鱼的耐盐性高于斑马鱼，而低于剑尾鱼的耐盐性；②丝足鱼稚、幼鱼间耐盐性存在着极显著差异，其耐盐性与日龄有关，日龄越大，耐盐性越强；③丝足鱼在盐度14半咸水中驯化48h左右渗透压基本调节平衡。实验证明经过从低盐度到高盐度的梯度驯化，丝足鱼可适应盐度为14的半咸水，为丝足鱼作为海水致病菌毒力分析模型奠定理论基础。

Salinity tolerance and salt water acclimation of gourami Trichogaster trichopterus

The salinity tolerance of gourami Trichogaster trichopterus was examed in comparison with Danio rerio and Xiphophorus helleri.Five parameters,including mean survival time(MST),50% survival time(ST_(50)),96h median lethal salinity(LS_(50)-96?h),beginning time of death occurring(BTOD),and mortality,were measured.The salt water acclimation of gourami T.trichopterus and serum osmotic pressure of the gourami after different acclimating time at salinity 14 were studied.The major results were as follows.1) The salinity tolerance of T.trichopterus is stronger than D.rerio,but it is weaker than X.helleri.2) The difference of salinity tolerance is highly significant between juvenile and young of gourami T.trichopterus,and the salinity tolerance is related to the age.The older animals have the stronger salinity tolerance;.3) Serum osmotic pressure of the gourami T.trichopterus is in equilibrium after 48 hours at salinity 14.Generally,after acclimation from low salinity to high salinity step by step,gouramis T.trichopterus can tolerate 14 salinity safely.The results lay a theoretical foundation for T.trichopterus as an infection model to analyze the pathogenicity of sea water bacteria.