Mechanical nociceptive thresholds are regularly used to determine the efficacy of analgesic agents both experimentally and clinically in a variety of species. The 'pressure of palpation device' (PPD) was developed for use in cats and is a small battery operated device with a finger-mounted force sensing resistor (FSR, Interlink Electronics, Northumberland. UK). The PPD was used in a study assessing the analgesic efficacy of pethidine after castration in cats. Pethidine was demonstrated to prevent the development of post-operative scrotal hypersensitivity for up to 2 hours after castration, whereas cats given no analgesics showed marked hyperalgesia immediately after surgery. Visual Analogue Scale (VAS) pain scores after castration showed a similar analgesic effect of pethidine. These results suggest that the PPD could become a useful research tool to assess the effectiveness of analgesic agents in the cat.