Pain evaluation in ovariohysterectomised albino wistar rats using physiological, behavioural and biochemical indices

Abstract

Twenty adult female albino wistar rats assigned randomly to four groups (GP1 – 4 ) were used to study the identification and measurement of post ovariohysterectomy (OVH) pain using physiological, behavioural and biochemical parameters. GP1 rats were given pentobarbitone (60mg/Kg body weight intraperitoneally) alone. GP2 rats were administered pentazocine at 1 0 mg/k g (intramuscularly) body weight and pentobarbitone at the same dose as GP1. OVH was not performed on rats in GP1 and GP2. GP3 and GP4 rats were anaesthetised as in GP1 and GP2 respectively and OVH was carried out. Blood glucose, daily feed intake, daily defeacation were measured once daily, while behavioural changes were measured twice daily and the mean indices for the day recorded. Data obtained from the different groups were subjected to ANOVA and post hoc LSD and values of p < 0.05 were considered significant. The rates of defeacation and the scores for feed intake and movement were significantly higher in GP1 and GP2 than in GP3 and GP4 while those for aggression were higher in GP3 and GP4 than GP1 and GP2. Pentazocine seemed to have improved these in dices significantly in GP3. The scores for avoidance of ventral abdominal contact and refusal to stand on hind limbs were significantly higher in GP3 and GP4 and did not differ significantly between the operated groups. Blood glucose levels and the scores for squinting of the eyes were not significantly different among the groups. These results appear to indicate that physiological and behavioural parameters can be used to identify pain in rats. They were however not sensitive enough to differentiate between the degree of these pain in rats.

Keywords: Pain assessment, Rats, Ovariohysterectomy