Pain has a profound effect on an animal’s wellbeing. In Germany, researchers using animals have been legally required to reduce any possible pain, suffering, distress or lasting harm to an absolute minimum since 1972. To evaluate how these provisions have been implemented in practice, an assessment of refinements to experimental techniques was conducted by retrospectively reviewing 684 surgical interventions described in 506 animal research applications that were sent to the German competent authorities for approval in 2010. This paper focuses on the efficacy of proposed anesthesia and peri- and postoperative analgesia. Postoperative analgesia was not proposed for 30% of surgeries. Following 10% of procedures, animals were to be given pain relieving medication if the investigators decided this was necessary; however, structured assessments to detect pain were absent. Consequences of unalleviated pain and omission of pain assessment techniques are discussed, and some recommendations to improve anesthesia and analgesia are given. The findings of this review highlight the need for improvement, both to fulfil legal requirements and to improve animal welfare. To monitor compliance with animal welfare regulations and ensure good veterinary and scientific practices, education and training need to be intensified. Adherence to the items listed in the PREPARE and ARRIVE guidelines and the Gold Standard Publication Checklist (GSPC) should become legally binding.
