A comparison of xylazine and methohexitone for the chemical immobilization of reeves' muntjac ( Muntiacus reevesi)

Abstract

The advantages and disadvantages of xylazine and methohexitone for immobilizing captive and free-living muntjac were compared. Twenty deer were immobilized with xylazine on 36 occasions, and 19 deer were immobilized with methohexitone on 26 occasions. Xylazine was unpredictable in its effects, particularly with free-living muntjac, and the protracted recovery phase severely restricted its value for field use. In comparison methohexitone was quick acting, the level of anaesthesia induced more controllable, and the recovery phase rapid. For the field biologist, who normally requires a short period of immobilization and a rapid recovery, methohexitone would appear to be preferable to xylazine for use with muntjac. The main disadvantage of methohexitone was that some animals underwent periods of excitatory behaviour during recovery, and so the deer had to be left in an open area clear of obstructions to recover. The extent of the excitatory behaviour could be reduced by avoiding unnecessary stimuli during the recovery period. Xylazine would be more appropriate where calm recovery was essential, such as with captive animals that must recover in a small enclosure or must be transported following sedation.