The aim of this preliminary study was to identify key behavioural indicators of pain in cats. The behaviour of cats before and after ovariohysterectomy was analysed using a detailed behavioural ethogram. A comparison of behaviours between cats given pre-operative analgesia only and cats given both pre- and post-operative analgesia indicated that both groups demonstrated changed behaviour following surgery, compared to a control group of cats which underwent anaesthesia but not surgery. However, some specific postures, such as ‘half-tucked-up’ and ‘crouching’, were identified that occurred with greater frequency in the cats receiving pre-operative analgesia only, as compared to those receiving additional post-operative analgesia. This indicates that there are some key behaviours that may be useful in determining pain in cats. Routine administration of pre- but not post-operative analgesia may be ineffective for adequately alleviating pain in cats.