Behavioural and clinico-physiological studies on xylazine-ketamine and midazolam-ketamine anaesthesia in dogs

The present study was conducted on 12 dogs brought for various surgical interventions, which were randomly divided into two groups, I and II. In group I, midazolam (0.4 mg/kg, i.v.) and in group II, xylazine (0.5 mg/kg, i.m.) were administered as preanaesthetics. After 5 min, ketamine was administered i.v. (10 mg/kg body wt.) to induce surgical anaesthesia in animals of both groups. Different behavioural signs, induction and recovery time, and physiological parameters such as rectal temperature, heart and pulse rates and respiratory rate were recorded at different intervals. In group I, a significant increase in heart rate and pulse rate was observed, with no significant changes in rectal temperature and respiratory rate. In group II, a significant decrease in respiratory rate was observed at 15 min interval, but no significant changes were seen in rectal temperature, heart rate and pulse rate. Both the anaesthetic combinations provided satisfactory surgical anaesthesia with adequate analgesia and muscle relaxation. Midazolam-ketamine combination provided a rapid induction of anaesthesia as well as quick and smooth recovery as compared to xylazine-ketamine combination. Midazolam-ketamine combination was considered better than xylazine-ketamine for short duration of anaesthesia in dogs.