Refinement of research using ferrets (Mustela putorius furo): from pain detection to housing preferences

1: Facial expressions have proven to be a reliable method for the assessment of pain in animals. This relatively new approach to get insight in the pain experience of animals is not yet developed for ferrets. Therefore, we attempted to modify existing scales for other animals for the use in ferrets. For this purpose, ferrets that underwent intra-peritoneal transponder implantation for another study were used. Photographs were taken before and after the surgery to analyse changes in their facial expressions and with these images the Ferret Grimace Scale (FGS) was developed. It has yet to be proven to be accurate, so a follow-up study has to take place. If this scale turns out to be reliable, this measure of pain may provide insight into the subjective pain experience and can be a useful tool to eventually reduce pain in ferrets. 2: Little is known about suitable housing conditions for ferrets (Mustela putorius furo) and its effect on animal welfare, while ferrets are often used in laboratories and kept as pets. Knowing what their preferences regarding housing conditions are and implementing this would be beneficial to their wellbeing. We conducted a preference test regarding the ferrets sleeping, playing and drinking choices. This showed that ferrets have strong preferences for certain enrichments during specific activities. Firstly, they almost always slept together in the hammock and very little in the ferret ball. Second, ferrets did not show a real preference for playing either with the hammock or the ferret ball, but this activity was performed mostly alone. Finally, ferrets showed a strong preference for drinking out of a water bowl compared to a water bottle. Therefore, it would be preferable to house ferrets together, but give them a choice to do activities alone, provide them with a hammock so they can sleep comfortably and give them a water bowl as well as a bottle to drink from. When taking these preferences into account, the wellbeing of ferrets can be im