The effects of ovariohysterectomy plus different combinations of halothane anaesthesia and butorphanol analgesia on behaviour in the bitch.

One hundred and sixty-six behaviours were identified as possible indices of post-operative pain-induced distress in the bitch. These were assessed in bitches after treatment with different combinations of halothane and butorphanol in the absence of surgery and following ovariohysterectomy under halothane anaesthesia with or without butorphanol analgesia given at different stages during the operation. Behaviour was monitored while the bitches were alone (non-interactive) and when routinely examined and handled prior to blood sampling (interactive). Seventy-six of the 166 behaviours occurred so infrequently (less than two occurrences per hour) as to be of no value as indices. Non-interactive behaviours associated with surgery were a decrease in normal speed cage circling and an increase in drawing the rear limbs up in the pike position. The infrequent non-interactive behaviours of incision licking, vomiting and flank gazing were considered to be expressions of pain caused by ovariohysterectomy. During the post-surgical period, bitches given analgesic moved less frequently than those not receiving analgesic. Vocalisation was associated with dysphoria of analgesia rather than pain-induced distress. The behaviour of bitches after ovariohysterectomy suggests that this is a painful procedure which warrants analgesia.