Clinical effects of azaperone-metomidate, as compared to propionylpromazine-xylazine-metomidate or xylazine-ketamine combinations in anaesthesia of dogs.

Eighteen dogs of Tanzanian breeds divided into three groups of 6 were anaesthetized using either azaperone-metomidate (2 mg/kg, i.m. and 10 mg/kg i.p., respectively), propionyl promazine-xylazine-metomidate (2 mg/kg i.m., 1 mg/kg i.m. and 10 mg/kg i.p., respectively), or xylazine-ketamine (1 mg/kg i.m. and 11 mg/kg i.m., respectively). The clinical effects on respiration rate, heart rate and body temperature were studied until recovery. Hypersensitivity to noise was associated with azaperone metomidate anaesthesia. The other combination produced a smooth and uneventful induction and recovery from anaesthesia. Muscle relaxation and analgesia were adequate in all groups. Duration of xylazine-ketamine anaesthesia was shortest (30 +/- 5 minutes) followed by azaperone metomidate (50 +/- 15 minutes) and the longest duration was with propionyl promazine-xylazine-ketamine (120 minutes). Azaperone and metomidate was associated with marked increases in cardiac and respiration rates and marked hypothermia, which persisted throughout. Minimal changes were observed in the other combinations. Azaperone-metomidate seems to be preferable due to the moderate period of anaesthesia adequate for most operations. However, all the three combinations offer a practical application because of the convenient route of administration.