A combination of alfaxalone, medetomidine and midazolam for the chemical immobilization of Rhesus macaque (Macaca mulatta): Preliminary results.

BACKGROUND: Chemical immobilization of non-human primates can be required to perform scientific or veterinary procedure with different invasiveness degrees. This preliminary study was undertaken to assess the clinical effects of a combination of alfaxalone, medetomidine and midazolam (AMM).

METHODS: Seven rhesus macaques were chemically immobilized, for invasive veterinary procedures, with alfaxan 2 mg kg-1 , medetomidine 20 μg kg-1 and midazolam 0.3 mg kg-1 injected subcutaneously.

RESULTS: The alfaxalone combination induced surgical anaesthesia, with a complete absence of response to noxious stimuli, for at least 20 minutes. The total duration of anaesthesia was 56 ± 7 minutes, and the administration of atipamezole, to partially reverse the combination effects, did not appear to alter the depth of anaesthesia.

CONCLUSION: In conclusion, the AMM combination produced rapid onset general anaesthesia, following subcutaneous administration of a relatively low volume (0.28 mL/kg) of injectate.