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This study compared pressure and thermal thresholds after administration of three opioids in eight cats. Pressure stimulation was performed via a bracelet taped around the forearm. Three ball-bearings were advanced against the forearm by inflation of a modified blood pressure bladder. Pressure in the cuff was recorded at the end point (leg shake and head turn). Thermal threshold was tested as previously reported using a heated probe held against the thorax [Dixon et al. (2002)Research in Veterinary Science, 72, 205]. After baseline recordings, each cat received subcutaneous methadone 0.2 mg/kg, morphine 0.2 mg/kg, buprenorphine 0.02 mg/kg or saline 0.3 mL in a four period cross-over study. Measurements were made at 15, 30, 45 min and 1, 2, 3, 4, 8, 12 and 24 h after the injection. Data were analysed by anova (P < 0.05). There were no significant changes in thresholds after saline. Thermal threshold increased at 45 min after buprenorphine (maximum 2.8 ± 3 °C), 1–3 h after methadone (maximum 3.4 ± 1.9 °C) and 45 min to 1 h (maximum 3.4 ± 2 °C) after morphine. Pressure threshold increased 30–45 min (maximum 238 ± 206 mmHg) after buprenorphine, 45–60 min after methadone (maximum 255 ± 232 mmHg) and 45–60 min and 3–6 h (maximum 255 ± 232 mmHg) after morphine. Morphine provided the best analgesia, and methadone appears a promising alternative. Buprenorphines limited effect was probably related to the subcutaneous route of administration. Previously, buprenorphine has produced much greater effects when given by other routes.