Speare Rick, Speare Benjamin, Muller Reinhold, Bishop Phil
J Zoo Wildl Med. 2014 Sep;45(3):492-6. doi: 10.1638/2013-0088R.1.
Because anesthesia of amphibian larvae is currently problematic, the aim of this study was to test if a fish anesthetic containing approximately 500 g/L isoeugenol (Aqui-S) could anesthetize tadpoles. Three concentrations of Aqui-S were tested (of commercial solution 10, 20, and 50 microl/L) with 10 tadpoles of the southern brown tree frog (Litoria ewingii) per concentration. Tadpoles were anesthetized for 15 min in water at 18-20 degrees C. Anesthetic criteria included four time points and two heart rates: time to loss of response to stimulation, loss of righting reflex, and return of spontaneous movement and of righting reflex after removal from Aqui-S, and heart rate after induction and after 15 min of anesthesia. No tadpole showed signs of irritation or excitement, no tadpole died, and all returned to normal behavior. The times for induction of anesthesia (time to loss of righting reflex) decreased significantly (P < 0.001) with increasing concentration: means of 27.5, 16.8, and 5.7 min for 10, 20, and 50 microl/L, respectively. Heart rate after 15 min of anesthesia was significantly lower (P = 0.006) for concentrations of 20 and 50 microl/L compared to 10 microl/L. At the lowest concentration (10 microl/L), anesthesia was light. Recovery times were significantly delayed (P < 0.001) for 50 microl/L, approximately double those for the lower concentrations. Spontaneous movements began at 56.9, 51.4, and 119 min for 10, 20, and 50 microl/L Aqui-S, respectively. Although Aqui-S did anesthetize tadpoles at all three concentrations, with 20 microl/L being the most suitable, additional longer-term toxicity testing is required prior to its adoption as an anesthetic agent for this species. Anesthesia, isoeugenol, Litoria ewingii, southern brown tree frog, tadpoles.
由于目前两栖类幼体的麻醉存在问题，本研究的目的是测试一种含约500 g/L异丁香酚的鱼类麻醉剂（Aqui-S）能否麻醉蝌蚪。测试了三种浓度的Aqui-S（市售溶液分别为10、20和50微升/升），每种浓度用10只南方褐树蛙（Litoria ewingii）蝌蚪。蝌蚪在18 - 20摄氏度的水中麻醉15分钟。麻醉标准包括四个时间点和两个心率：对刺激失去反应的时间、翻正反射消失的时间、从Aqui-S中取出后自发运动和翻正反射恢复的时间，以及诱导后和麻醉15分钟后的心率。没有蝌蚪表现出刺激或兴奋的迹象，没有蝌蚪死亡，所有蝌蚪都恢复了正常行为。随着浓度增加，麻醉诱导时间（翻正反射消失时间）显著缩短（P < 0.001）：10、20和50微升/升的平均诱导时间分别为27.5、16.8和5.7分钟。与10微升/升相比，20和50微升/升浓度麻醉15分钟后的心率显著降低（P = 0.006）。在最低浓度（10微升/升）时，麻醉较浅。50微升/升浓度的恢复时间显著延迟（P < 0.001），约为较低浓度的两倍。10、20和50微升/升Aqui-S溶液中蝌蚪自发运动开始的时间分别为56.9、51.4和119分钟。虽然Aqui-S在所有三种浓度下都能麻醉蝌蚪，其中20微升/升最为合适，但在将其用作该物种的麻醉剂之前，还需要进行额外的长期毒性测试。麻醉、异丁香酚、Litoria ewingii、南方褐树蛙、蝌蚪。
