Pain evaluation in animals requires the use of evaluation scales, which depend on the interpretation made by observers. The present study aimed to evaluate the correlation between visual analog scale (VAS), Melbourne pain scale and Von Frey filaments in the evaluation of post-operatory pain in fourty two healthy adult bitches submited to ovariohysterectomy. Post-operatory pain was evaluated by two observers unaware of the analgesic protocol used, in one-hour intervals, using VAS, Melbourne pain scale and Von Frey filaments, applied around the surgical wound. A score of 50mm in VAS or 13 points in the Melbourne pain scale were considered as the criterion for analgesic administration. VAS and Melbourne pain scale showed a good correlation, with r=0.74. Correlation between VAS and Von Frey filaments was weak (r=-0.18). Correlation between Melbourne pain scale and Von Frey filaments was -0.37. VAS revealed to be the most sensitive scale. VAS and Melbourne pain scale showed a good correlation degree. It was concluded that a lower score in the Melbourne pain scale can be considered as criterion for analgesic administration.
pain; analgesia; evaluation methods; dogs