As part of a more broad study about sheep scab, the relationship between an infection with Psoroptes ovis and nocturnal rubbing and lying behaviour was examined. Groups of 6 to 20 scab-free sheep were penned with one infested sheep. The variation in the rubbing behaviour depended on the age of the lesion, the size of the infected area and the amount of time that has elapsed since the infected sheep was introduced. Older and larger lesions resulted in an increase in the rubbing behaviour. The more time the sheep spent rubbing resulted in the sheep spending less time, overall, lying. As well, lying bouts were more frequently interrupted by rubbing bouts. In general, this study demonstrated how a parasitic infection can generate changes in the behaviour of the sheep and these changes may affect the welfare and transmission of the disease.