丁香油不同使用方式对克氏原螯虾麻醉效果的影响

Effects of different application methods of clove oil on anesthetic effect of red swamp crayfish Procambarus clarkii

为减少克氏原螯虾Procambarus clarkii在实际生产和科学研究过程中人为操作造成的应激损伤,选择丁香油-乙醇溶液作为麻醉剂,将丁香油和乙醇溶液按体积比为1∶1.5混合溶解后再溶于水,配制成不同浓度的麻醉剂(1~8 g/L,8~20 g/L),使用喷洒和浸浴方式麻醉不同规格(6.17 g±0.20 g、29.54 g±0.30 g)的克氏原螯虾,通过观察麻醉时间、行为学特征,以及测定耗氧率和氧化应激指标等,分析了丁香油-乙醇溶液的麻醉效果。结果表明:随着麻醉剂浓度的升高,克氏原螯虾麻醉时间缩短,复苏时间延长,小规格和大规格克氏原螯虾浸浴麻醉的丁香油-乙醇适宜浓度分别为8、20 g/L,喷洒麻醉的适宜浓度分别为4、16 g/L;喷洒麻醉效果显示,螯足的行为和形态特征可作为评判标准,将麻醉分为4个阶段;两种麻醉方式均显著降低了虾的耗氧率(P<0.05),麻醉效果显著,且喷洒麻醉的虾耗氧率及SOD、CAT酶活性均显著低于浸浴麻醉(P<0.05)。研究表明,喷洒和浸浴两种方式均可用于克氏原螯虾麻醉,与浸浴麻醉相比,体表喷洒麻醉显著降低了克氏原螯虾的耗氧率,对个体鳃组织应激损伤较小,麻醉效果更好。

In order to reduce the stress damage of red swamp crayfish Procambarus clarkii caused by human operation during the actual production and scientific research,small red swamp crayfish with body weight of(6.17±0.20)g were bathed in and sprayed with the mixture of clove oil and ethanol solution at a volume ratio of 1∶1.5 at a dose of 1,2,4,and 8 g/L and 8,10,16,and 20 g/L,respectively.Large red swamp crayfish with body weight of(29.54±0.30)g were bathed in and sprayed with the same mixture of clove oil and ethanol solution at a dose of 10,16,20,and 24 g/L and 8,10,16,and 20 g/L,respectively for anesthesia.The results showed that with the increase in anesthetic agent concentration,the anesthetic time was found to be shortened and the recovery time to be prolonged,with the appropriate concentrations of 8 g/L in small size crayfish and 20 g/L in large size ones,and the appropriate concentrations of 4 g/L for spray anesthesia and 16 g/L for bath.The red swamp crayfish with spraying anesthesia showed cheliped behavior that was used as a criterion to divide anesthesia into four stages.Significant decrease in oxygen consumption and anesthetic effect was observed in both methods of anesthesia(P<0.05).There were significantly lower oxygen consumption rate and SOD and CAT enzyme activities in the red swamp crayfish with spraying anesthesia than those in the crayfish with immersion anesthesia(P<0.05).The findings indicated that both spraying and immersion anesthesia were used for red swamp crayfish anesthesia,especially surface spraying anesthesia being featured by significant decrease in the oxygen consumption rate and less stress damage to individual gill tissue,and better anesthesia effect compared with the immersion anesthesia.