Evaluation of score parameters for severity assessment of surgery and liver cirrhosis in rats

Abstract Severity assessment in animals is an ongoing field of research. In particular, the question objectifiable and meaningful parameters score-sheets, as well their best combination, arise. This retrospective analysis investigates suitability a score-sheet for assessing severity seeks to optimise it predicting survival 89 male Sprague Dawley rats ( Rattus norvegicus ), during experiment evaluating influence liver cirrhosis by bile duct ligation (BDL) on vascular healing. The following five were compared predictive power: (i) overall score; (ii) relative weight loss; (iii) general condition (iv) spontaneous behaviour (v) observer’s whether pain might be present. Suitable cut-off values these individual combination multiple investigated. A total ten (11.2%; 10/89) died or had sacrificed at early stage due pre-defined humane endpoints. Neither score nor any parameter yielded satisfactory results survival. Using retrospectively calculated combining with animal required analgesia (dipyrone) relief resulted improved prediction second post-operative day. study demonstrates that was more suitable than using single ones experienced human judgement can useful addition objective severity. By optimising better understanding burden model rats, this contributes welfare.