Behavioural responses of mice to the odour of cat blood and horse blood

Abstract: A variety of prey species are able to detect predators by odours emanating from their urine, feces, fur and anal glands. However, it is unknown whether the odour of a predator’s blood also contains information signalling “predator” to a prey. The aim of the present study was therefore to assess if blood odour from a cat elicits avoidance or anxiety responses in CD-1 mice (Mus musculus). A two-compartment test arena was used to assess place preference, motor activity and fecal excretions when the mice were simultaneously presented with cat blood and a blank control. Additionally, the mice were tested with horse blood and N-pentyl acetate, a fruity odour. The mice did not show avoidance of any of the three odours. Nevertheless, the mice were significantly less active when exposed to cat blood in comparison to horse blood, but did not increase defecation when exposed to cat blood. This suggests that the information mice get by the odour of cat blood did not contain the signal “predator”.