Lavalle Christine, Clarence Stacey, Khan Hufsa, Shires Kallie, Parrott Joanne
Environment and Climate Change Canada, Burlington, Canada.
Lab Anim. 2025 Jun;59(3):319-331. doi: 10.1177/00236772241288146. Epub 2025 Jan 25.
This paper reviews the methods and approaches used to humanely anesthetize (render unconscious) and or euthanize (kill) laboratory fish (in research settings), with a specific focus on the fathead minnow. We surveyed the literature (333 scientific studies published 2004-2021) to examine euthanasia methods used for various life stages. Our findings showed that many published scientific papers do not provide an adequate description of anesthesia or euthanasia methods, particularly for larval fathead minnows. Over the two decades there was a 20% increase in the number of papers that described their euthanasia method(s). In addition, the review shows evidence that younger minnows require higher concentrations of anesthetic (compared with adults) for effective euthanasia. Recommendations from the review include the use of a two-step euthanasia method (immersion in anesthetic followed by spinal severance and/or exsanguination). As well, it is recommended that details of anesthesia and euthanasia are more fully captured in published scientific manuscripts to allow for comparison among studies and for progress in animal welfare methods. Specific research questions remain on whether rapid cooling is a humane first-step euthanasia method, better investigations into understanding when anesthesia has occurred in fish, and research into methods of euthanasia in larval and juvenile fish.
本文回顾了在研究环境中对实验用鱼（特别是黑头呆鱼）进行人道麻醉（使其失去意识）和/或安乐死（杀死）所使用的方法和途径。我们查阅了文献（2004年至2021年发表的333项科学研究），以研究用于不同生命阶段的安乐死方法。我们的研究结果表明，许多已发表的科学论文没有充分描述麻醉或安乐死方法，特别是对于黑头呆鱼幼体。在这二十年中，描述其安乐死方法的论文数量增加了20%。此外，该综述表明有证据显示，与成年鱼相比，幼龄呆鱼需要更高浓度的麻醉剂才能有效实施安乐死。该综述提出的建议包括采用两步安乐死方法（先将鱼浸入麻醉剂，然后进行脊髓切断和/或放血）。同样，建议在已发表的科学手稿中更全面地记录麻醉和安乐死的细节，以便进行研究间的比较以及推动动物福利方法的进步。关于快速降温是否是一种人道的第一步安乐死方法、对鱼类何时进入麻醉状态进行更好的研究以及对幼鱼和稚鱼安乐死方法的研究，仍存在具体的研究问题。
