福尔马林药浴防治红鳍东方鲀异沟虫病的研究

异沟虫是红鳍东方鲀常见寄生虫之一,对红鳍东方鲀养殖业危害极大。为有效防治异沟虫病,在观察异沟虫虫卵孵化规律的基础上,研究评价福尔马林药浴对异沟虫的杀灭效果及其对红鳍东方鲀的安全性,形成红鳍东方鲀异沟虫病的防治方案。试验结果发现,异沟虫虫卵的孵化过程大致可分为孵化初期、孵化中期、孵化后期和破卵4个阶段,在17~19 ℃条件下,异沟虫虫卵5.5 d孵化出幼虫,8 d孵化结束;不同大小的异沟虫对福尔马林的耐受性有明显差异,当福尔马林剂量为600 mL/m 3 时,浸浴1 h可杀灭全部异沟虫幼虫(体长≤1 cm),但对异沟虫成虫(体长>1 cm)几乎无效;在600 mL/m 3 福尔马林浸浴条件下,红鳍东方鲀在浸浴后第5 h开始出现游动异常、呼吸困难等现象,在浸浴后第6 h出现死亡;而在650、700 mL/m 3 福尔马林浸浴条件下,红鳍东方鲀分别在浸浴后第5.5 h和4 h出现死亡。综上,体质量约为20 g的红鳍东方鲀异沟虫病的建议防治方案为600 mL/m 3 福尔马林溶液浸浴1 h,8 d后重复药浴1次。

Prevention of Parasite Heterobothrium tetrodonis in Infected Tiger PufferTakifugu rubripes by Formalin

Heterobothrium tetrodonis is one of the most common and important parasites in tiger puffer Takifugu rubripes , which is considered to be extremely harmful to tiger puffer aquaculture. In order to better control the disease of H. tetrodonisis , this study reported the process of hatching, evaluated the killing effect and safety of formalin on tiger puffer, and formed the prevented plan for H. tetrodonis . The results indicated that (1) the parasite incubation was roughly divided into four stages: initial stage of incubation, middle stage of incubation, late stage of incubation, and hatching. Under the conditions of 17—19 ℃, the larvae appeared in 5.5 days, the hatching finished on 8 days;(2) significant differences in formalin tolerance between different sizes of the worm were observed, and 600 mL/m 3 formalin bath for 1 h killed all the larvae of H. tetrodonis (body length≤1 cm), but little killed the adult worm (body length>1 cm);(3) exposuring to 600 mL/m^( 3) of formalin medicated bath, swimming abnormal and expiratory dyspnea of tiger puffer juveniles were observed to be existed after 5 h medicated bath, the time of death of tiger puffer juveniles occurred after 6 h medicated bath. In summary, our results suggested that disease treatment of H. tetrodonis be around 600 mL/m ³ formalin medicated bath for 1 h, and then once again after 8 days.