不同条件下2-苯氧乙醇对扁吻鱼幼鱼的麻醉效果

Effects of 2-phenoxyethanol as anaesthetics on juvenile Aspiorhynchus laticeps under different conditions

以麻醉剂2-苯氧乙醇浓度(50、100、200、400、600、800、1 000μL/L)、暴露时间(2、4、8、12、16、32 min)和溶解氧浓度(4、8、12、16、18、22 mg/L)作为参考指标,研究2-苯氧乙醇对扁吻鱼(Aspiorhynchus laticeps)幼鱼[(9. 91±0. 31) g]的麻醉效果。结果表明:麻醉时间与麻醉浓度呈负相关,复苏时间与麻醉浓度呈正相关。当浓度≤200μL/L,扁吻鱼幼鱼的呼吸频率在初期会下降,随后上升并维持在11次/10 s,当浓度≥400μL/L时,呼吸频率随着麻醉时间的增加下降,直至休克。当浓度为800和1 000μL/L时,幼鱼可在3 min内麻醉,并且在5 min内苏醒,因此,扁吻鱼幼鱼的最适麻醉浓度范围为800～1 000μL/L。在高浓度麻醉下,随着暴露时间的增加,幼鱼的复苏时间减短,当暴露32 min时,幼鱼仅(100. 51±10. 60) s就可以复苏(P <0. 05)。不同氧浓度下,幼鱼的复苏时间存在差异,其中12 mg/L最低只需(129. 00±36. 50) s,22 mg/L最高需(406. 33±53. 20) s,是12 mg/L的3. 15倍(P <0. 05)。

Aspiorhynchus laticeps belongs to Osteichyes,Cyprinformes,Aspiorhynchus Kessler,and was mylopharyngondon piceus.A.laticeps was national level to protect animals,so it had very important economic and scientific values.Because 2-phenoxyethanol was easy preparation,low price and rapid action,it acts as a general anaesthetics in fish.This paper regarded anaesthetics concentration(50,100,200,400,600,800,1 000μL/L),exposure duration(2,4,8,12,16,32 min)and dissolved oxygen concentration(4,8,12,16,18,22 mg/L)as reference indices,and the effects of 2-phenoxyethanol were focused on as anaesthetics on juvenile A.laticeps(9.91±0.31g).Result showed that induction time and anaesthetics concentration were negative correlation,however recovery time and anaesthetics concentration were positive correlation.Respiratory rate of A.laticeps would decrease when concentration under 200μL/L in initial period,but would be 11times/10s at mid-late period.Opercular movement frequency decreased with increasing doses of anaesthetics when concentration was equal or greater than 400μL/L,and at last.juvenile A.laticep would cease respiration.Juvenile A.laticep could be anaesthetized in less than 3 min,with recovery in less than 5 min at 800 and 1 000μL/L,so effective anaesthesia range was from 800 to 1 000μL/L.In high concentrations,recovery time decreased with increasing exposure time.Juvenile A.laticep could recover in(100.51±10.60)seconds(P<0.05.Because of different dissolved oxygen concentration,there were differences between recover time:12 mg/L would recover in less than(129±36.50)seconds,which was lowest.22 mg/L would recover in(406.33±53.20)seconds,which was highest.The highest group was 3.15 times higher than the lowest group(P<0.05).