Ellis, L. H., Wells, D. L. 2010. The influence of olfactory stimulation on the behaviour of cats housed in a rescue shelter. Applied Animal Behaviour Science 123(1-2), 56-62.

A wide variety of feline species have been shown to gain welfare benefits from the introduction of olfactory stimuli to the captive environment. The effect of this stimulation on the domestic cat, however, has been largely overlooked. This study thus explored the influence of olfactory stimulation on cats housed in a rescue shelter to determine whether it holds any value as a method of enrichment for this species. One hundred and fifty cats were randomly assigned to one of five conditions of olfactory stimulation (control [an odourless cloth]; biologically relevant odour [a cloth impregnated with the scent of rabbit]; biologically non-relevant odours, [a cloth impregnated with lavender, a renowned relaxant, or the scent of catnip, a well known stimulant]). Cats were exposed to the relevant olfactory stimuli for 3 h a day for five consecutive days. Each cat's behaviour was recorded every 5 min on days one, three and five of olfactory exposure, using instantaneous scan sampling. Overall, cats showed relatively little interest in the cloths, spending just over 6% of the total observation time interacting with these stimuli. However, animals exposed to the catnip-impregnated cloths exhibited significantly more interest in the stimulus than animals exposed to the other cloths, spending an average of 11.14% of the observation time interacting with the objects. Across all experimental conditions, interest in the cloths was significantly lower in the second and third hours of stimulus presentation compared to the first, suggesting habituation. Certain components of the cats' behavioural repertoire were influenced by olfactory stimulation. Catnip and prey scent encouraged a significantly higher frequency of behaviours indicative of reduced activity (e.g. more time sleeping, less time standing and actively exploring the environment) in comparison to the control condition. Catnip also encouraged play-like behaviour characterised as the 'catnip response'. Overall, the results suggest that certain odours, notably catnip, may hold potential as environmental enrichment for captive domestic cats.