Laboratory of Laboratory Animal Science and Medicine, School of Veterinary Medicine, Kitasato University, 35-1 Higashi-23, Towada, Aomori 034-0021, Japan.
Exp Anim. 2024 Jul 9;73(3):234-245. doi: 10.1538/expanim.24-0010. Epub 2024 Feb 22.
Accurately and promptly assessing pain in experimental animals is extremely important to avoid unnecessary suffering of the animals and to enhance the reproducibility of experiments. This is a key concern for veterinarians, animal caretakers, and researchers from the perspectives of veterinary care and animal welfare. Various methods including ethology, immunohistochemistry, electrophysiology, and molecular biology are used for pain assessment. However, the grimace scale, which was developed by taking cues from interpreting pain through facial expressions of non-verbal infants, has become recognized as a very simple and practical method for objectively evaluating pain levels by scoring changes in an animal's expressions. This method, which was first implemented with mice approximately 10 years ago, is now being applied to various experimental animals and is widely used in research settings. This review focuses on the usability of the grimace scale from the "cage-side" perspective, aiming to make it a more user-friendly tool for those involved in animal experiments. Differences in facial expressions in response to pain in various animals, examples of applying the grimace scale, current automated analytical methods, and future prospects are discussed.
准确、及时地评估实验动物的疼痛对于避免动物不必要的痛苦和提高实验的可重复性至关重要。从兽医护理和动物福利的角度来看，这是兽医、动物饲养员和研究人员非常关注的问题。目前已经有多种方法被用于疼痛评估，包括行为学、免疫组织化学、电生理学和分子生物学等。然而，面部表情疼痛评估法作为一种非常简单实用的客观评估动物疼痛水平的方法，已经得到了广泛的认可。该方法最初是在大约 10 年前应用于小鼠，现在已经被应用于各种实验动物，并在研究中得到了广泛的应用。本文综述了从“笼边”角度来看面部表情评估法的可用性，旨在使其成为动物实验参与者更友好的工具。讨论了不同动物对疼痛的面部表情差异、面部表情评估法的应用实例、当前的自动分析方法以及未来的前景。
