Combination of ketamine and xylazine for effective anaesthesia of juvenile chimpanzees (Pan troglodytes).

Intramuscular administration of ketamine at 15-20 mg/kg bodyweight provided effective levels of anaesthesia for venipuncture in 23 chimpanzees aged 12-36 months. For procedures such as plasmaphereses or percutaneous needle biopsy requiring longer anaesthetic times, xylazine (1 mg/kg) was given with the ketamine. More than 1600 procedures were performed under anaesthesia on the 23 chimpanzees over a period of 18 months with no mortality. Recovery was smooth and uneventful.