Pain behaviors before and after treatment of oral disease in cats using video assessment: a prospective, blinded, randomized clinical trial.

Background: Specific behaviors associated with pain in cats with oral disease have not been consistently studied. The aim of this exploratory study was to identify pain-induced behaviors in cats before and after treatment of oral disease using video assessment. Twenty-four cats (6 ± 3.3 years old; 4.9 ± 1.7 kg) were included in a prospective, blinded, randomized clinical trial. Cats were equally divided into minimal (G1: minimal dental treatment) or severe (G2: multiple dental extractions) oral disease groups. After acclimation at day 0, they underwent oral examination, radiographs, scaling, and dental extractions under general anesthesia (anesthetic protocol: acepromazine, hydromorphone, propofol, isoflurane, meloxicam, and local anesthetic blocks; day 1), and were discharged at day 6. Cats were filmed remotely for 10 min using a wide-angle glass lens camera before surgery (baseline) and throughout the study at different time points (36 h of video recording). The videos consisted of four parts namely general, playing, feeding and post-feeding behaviors. A board-certified behaviorist evaluated the duration/frequency of different behaviors based on an ethogram, which were analyzed using linear mixed models and a generalized linear model, respectively (p < 0.05).

Results: In comparison with baseline, duration of "not pawing the face" was significantly shorter at day 3 in G2. These cats spent significantly longer time "standing" and "laying" at days 3 and 6, respectively; G1 spent significantly less time "walking" and "standing" at days 3 and 4, respectively and significantly longer time "immobile" at day 3. Duration of "no/slow tail movement" was significantly longer in G2 than G1 at day 5. Duration of "pawing the ribbon" (playing) was significantly shorter in G2 than G1 at day 1. Feeding and post-feeding behaviors with soft food were not significantly different between groups or over time. Frequency of "difficulty grasping dry food" was significantly higher in G2 than G1 up to day 6. Frequency of post-feeding "head shaking" was significantly higher in both groups at day 6 when compared with baseline.

Conclusions: This study identified pain-induced behaviors in cats undergoing treatment of oral disease. These behaviors may be used to differentiate painful versus pain-free cats in clinical practice.