Stutler Shannon A, Johnson Eric W, Still Kenneth R, Schaeffer David J, Hess Rex A, Arfsten Darryl P
Vivarium Support Function, Operational Toxicology Branch, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA.
J Am Assoc Lab Anim Sci. 2007 Mar;46(2):13-20.
Euthanasia is one of the most commonly performed procedures in laboratory animal settings. The method of euthanasia may affect experimental results in studies using animals and must be compatible with research objectives including subsequent tissue analyses. Our present study was performed to evaluate the effects of 7 euthanasia methods on sperm motility in mature rats. Rats were euthanized using CO2, 2 commercially available euthanasia solutions (Beuthanasia-D and Sleepaway), and 4 volatile anesthetics (enflurane, halothane, isoflurane, and sevoflurane). Rats euthanized by rapid decapitation alone served as negative controls, and a-chlorohydrin-treated rats euthanized by rapid decapitation were positive controls for sperm impairment. For 5 of these methods, we also measured time to ataxia, recumbency, respiratory arrest, and no auscultable heartbeat. Immediately after euthanasia of each rat, distal caudal epididymides were removed; 1 was processed for automated sperm motility analysis, and the other was frozen for subsequent concentration analysis. Time to all measured parameters was less for volatile anesthetics than for Beuthanasia-D. Times to last respiration and no heartbeat were less for halothane and isoflurane than for enflurane and sevoflurane. Percentage motile sperm did not differ significantly between methods. Percentage progressively motile sperm did not vary significantly between methods except for Beuthanasia-D, for which it was significantly less than the negative control value. Specific sperm motion parameters for each euthanasia method except CO2 and Sleepaway varied significantly from the negative control. Our results indicate that the method of euthanasia is an important consideration when rat sperm motility parameters must be evaluated.
安乐死是实验动物环境中最常用的操作之一。安乐死方法可能会影响动物研究的实验结果，并且必须与包括后续组织分析在内的研究目标相兼容。我们目前的研究旨在评估7种安乐死方法对成年大鼠精子活力的影响。使用二氧化碳、两种市售安乐死溶液（Beuthanasia-D和Sleepaway）以及4种挥发性麻醉剂（恩氟烷、氟烷、异氟烷和七氟烷）对大鼠实施安乐死。仅通过快速断头处死的大鼠作为阴性对照，而经α-氯醇处理后通过快速断头处死的大鼠作为精子损伤的阳性对照。对于其中5种方法，我们还测量了出现共济失调、侧卧、呼吸停止和无法听诊到心跳的时间。对于挥发性麻醉剂，所有测量参数出现的时间均短于Beuthanasia-D。氟烷和异氟烷出现最后呼吸和无心跳的时间短于恩氟烷和七氟烷。各方法之间活动精子的百分比没有显著差异。除Beuthanasia-D外，各方法之间进行性活动精子的百分比没有显著变化，Beuthanasia-D的这一百分比显著低于阴性对照值。除二氧化碳和Sleepaway外，每种安乐死方法的特定精子运动参数与阴性对照相比差异显著。我们的结果表明，在必须评估大鼠精子活力参数时，安乐死方法是一个重要的考虑因素。
