Severity classification of surgical procedures and application of health monitoring strategies in animal research proposals: A retrospective review

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Animal experimentation has been one of the most controversial areas of animal use, mainly due to the intentional harms inflicted upon the animals used. In an effort to reduce these harms, research on refinement has increased significantly over the past 20 years. However, the extent to which these efforts have helped to reduce the severity of the research procedures, and thus animal suffering, is uncertain. To provide an indication of the awareness and implementation of refinement methods, we reviewed the experimental techniques for 684 surgical interventions described in 506 animal research applications that had been sent to the German competent authorities for approval in 2010. In this paper, we describe and discuss the severity categorisation of the proposed surgeries and the planned health monitoring strategies. We found that the researchers frequently underestimated the levels of pain, suffering, distress and lasting harm that were to be inflicted on the animals. Furthermore, the planned health monitoring strategies were generally flawed. To ensure responsible treatment of animals and high-quality science, adequate training of research workers in recognising and alleviating animal suffering is essential.