Retrospective analysis of elective health examinations as preventative medicine interventions at a zoological collection

A retrospective survey of outcomes from elective health examinations on amphibians, reptiles, birds and mammals in a zoological collection was carried out in order to compare differences between taxa, type of health examination and age of animal, and to quantify whether the benefits of such interventions exceed potential welfare risks to the subjects. Outcomes of 1651 health examinations, including import, pre-export, first and routine health examinations, were recorded and analysed. At least one problem was found in 45.7% of health examinations, with subsequent action (such as treatment, follow-up or further diagnostics) required in just under half of those animals or 21.1% of health examinations overall. A problem was identified in 52.1% of import examinations as opposed to 32.5% of pre-export examinations, and in 52.2% of routine examinations, compared to 33.6% of first examinations. When analysed further by taxon, these differences were not significant for all taxa. In addition, only for mammals was there a significant difference between age groups, with problems significantly more likely to be identified as age increased. A complication occurred during 3% of total health examinations, with complications significantly more likely to have been caused in birds than in mammals and none at all identified in reptiles and amphibians. Almost 97% of the complications caused during bird health examinations were minor wounds resulting from capture for the procedure.  Little has been published previously evaluating the effects of preventative medicine interventions on mortality, morbidity or welfare of zoo animals. This kind of information can be used to make evidence-based decisions on the necessity and frequency of elective health examinations in a particular collection.