丁香油和MS-222对大泷六线鱼幼鱼的麻醉效果

为研究丁香油和MS-222麻醉剂对大泷六线鱼Hexagrammos otakii的麻醉效果,选择体质量为(83.3±7.8)g的大泷六线鱼幼鱼进行试验,根据大泷六线鱼被麻醉和复苏时的行为特征,将整个麻醉过程分为10期,其中麻醉6个时期,复苏4个时期。结果表明:丁香油浓度在50~100 mg/L、MS-222浓度在50~70 mg/L时鱼体均可在3 min内入麻并均可在5 min内复苏;当丁香油浓度≥100 mg/L、MS-222浓度≥70 mg/L时,鱼体在麻醉液中浸浴15 min后部分鱼体出现休克死亡;用丁香油麻醉鱼时,整个麻醉过程中鱼体的呼吸频率呈下降趋势,而用MS-222麻醉鱼时,鱼体在达到4期阶段后呼吸频率明显加快,但仅见鳃盖后缘小幅度张合;鱼体进入深度麻醉以后在空气中暴露时间越长,鱼体复苏所需时间就越长,用丁香油或MS-222麻醉的鱼体可在空气中分别暴露7、5 min。研究表明,丁香油和MS-222均对大泷六线鱼幼鱼有良好的麻醉效果,具有入麻时间短、复苏快的特点,两者均可作为大泷六线鱼理想的麻醉剂。

Anesthesia effect of clove oil and MS-222 on juvenile fat greenling Hexagrammos otakii

Juvenile fat greenling Hexagrammos otakii with body weight of (83.3±7.8) g was anaesthetized by clove oil at a dose of 10, 20, 30, 40, 60, 80, 100 and 110 mg/L and by MS-222 at a doses of 10, 20, 30, 40, 50, 60 and 70 mg/L and by natural sea water as control and the respiratory rate was determined at water temperature of (15±0.5)℃ in the juveniles exposed to the clove oil and MS-222 at the doses, above to highlight the anesthetic effect of clove oil and MS-222 on fat greenling. The recovery time was determined in the fat greenling juveniles first exposed to the clove oil and MS-222 at a dose of 80 mg/L for 5 min and then exposed to air for 0, 3, 4, 5, 6, 7, 8 and 9 min. The anesthesia process is divided into 6 periods, and recovery process is classified into 4 periods de-pending on the behavioral characteristics of the fish. The results showed that the fat greenling became into anesthe-sia within 3 min and recovered within 5 min at clove oil concentration of 50-100 mg/L and MS-222 concentration of 50-70 mg/L. A few fish died of shock and less than 100% of recovery rate were observed in the fish exposed to clove oil concentration of over 100 mg/L and MS-222 concentration of 70 mg/L for 15 min anesthesia. The fish an-aesthetized by clove oil had low respiratory frequency, while the fish anaesthetized by MS-222 showed significantly accelerated breathing in the phase 4, with only small amplitude stretching posterior to operculum. The recovery time under deep anesthesia was found to be longer with time extension of air exposure, with the safe air exposure of 7 min in the anesthetic effect of clove oil, and the safe air exposure of 5 min in the anesthetic effect of MS-222. The findings indicate that clove oil and MS-222 as good anesthetics for fat greenling are characterized by short anesthe-sia time and quick recovery.