Computed Tomography as a Diagnostic Tool for Evidence Based Euthanasia in Captive Ursids
Bears (Ursidae) are commonly kept under human care and regularly live beyond their average lifespan in the wild (Föllmi et al. 2007). Nevertheless, a variety of factors such as genetics, disease, stress, nutrition, lack of exercise and environmental conditions contribute to the development of age-related health issues often significantly affecting animal wellbeing. The aim of this case study was to demonstrate the use of full body computed tomography as diagnostic tool in bears and its importance for evidence based, humane euthanasia in case of animal welfare relevant findings. Ten bears of three different species (Eight Ursus arctos, one Tremarctos ornatus and one Melursus ursinus) presenting with unspecific clinical symptoms underwent computed tomography at the Leibniz-Institute of Zoo and Wildlife Research Berlin. In all animals examined skeletal disorders, such as osteoarthrosis and vertebral spondylosis could be diagnosed. Furthermore, dental disease and neoplastic processes of various organ systems, e.g., mammary adenocarcinoma and parotideal neoplasia, were commonly encountered (n=6). Reproductive and gastrointestinal disorders were each discovered in three animals. Cardiovascular, and lymphatic lesions were found in two and one animal, respectively. Based on these findings seven bears were euthanized and three animals received further treatment. Deceased animals underwent immediate necropsy. Comparison of radiological and pathological findings showed that computed tomography is a valuable diagnostic tool to objectively assess health and prognosis of diseased captive Ursids.
The authors would like to thank FOUR PAWS International, Wildpark Johannismühle, Zoo Berlin and Tierpark Berlin for their contribution to the project.
1. Föllmi J, Steiger A, Walzer C, Robert N, Geissbühler U, Doherr M G, Wenker C. A scoring system to evaluate physical condition and quality of life in geriatric zoo mammals. Animal Welfare. 2007;16(3):309–318.