鲆鲽类循环水养殖系统中病原菌的分布及杀除工艺

以半滑舌鳎皮肤溃疡病的致病菌灿烂弧菌Vibrio splendidus和哈维氏弧菌Vibrio harveyi为指示菌，研究了循环水养殖系统各环节中细菌分布和消除工艺。结果表明，不健康的苗种携带病原菌进入养殖系统后，可分布在残饵、池壁污物、养殖工具及循环水各处理环节。而弧形筛过滤、曝气池气升、紫外线消毒是循环水养殖系统消除细菌的三大环节。用5×10-6 mol/L的KMnO4溶液浸泡工具2h，对细菌的杀灭率达到100%；用25×10-6 mol/L的KMnO4溶液擦拭养殖池壁污物1.5min后，细菌杀灭率高于90%；用100×10-6 mol/L浓度的H2O2溶液对养殖舌鳎病鱼进行药浴消毒处理10min，对体表细菌的杀灭率达到了94.49%。对鲆鲽鱼类循环水养殖系统中细菌的分布和消除效果进行了系统研究，研究结果可为建立循环水健康养殖工艺提供理论数据和参考。

Pathogenic bacteria distribution and extermination in the recirculating aquaculture system of flatfish

The water purification process includes filtration of arc screen, strong aeration, biological filtration and UV sterilization in the recirculating aquaculture system (RAS). The pathogens of skin ulceration, Vibrio splendidus and Vibrio harveyi were selected to be the indicator bacteria for study on bacterial distribution and extermination in RAS of flatfish Cynoglossus semilaevis. Pathogens were found in the feed residues, organic sediment on the tank wall and each instrumental compartment of RAS. Unhealthy fish seedlings and tools used in the cultivation could also bring pathogens into the culture system. Extermination trials illustrated that the filtration of arc screen, strong aeration and UV sterilization were important in the elimination of bacteria. The disinfection rate of pathogens in the organic sediment on tank wall was higher than 90% by washing with KMnO4 at a concentration of 25×10-6 mol/L for 1.5min. While the disinfection rate of pathogens on the body surface of the flatfish reached 94.49% by being soaked in H2O2 at a concentration of 100×10-6 mol/L for 10min. This is the first report on the distribution and extermination of pathogenic bacteria in RAS of flatfish, which will provide theoretical data and reference for the management of RAS.