Capture and immobilisation of aardvark (Orycteropus afer) using different drug combinations : research communication

Abstract

Nine aardvarks (<em>Orycteropus afer</em>) were captured in the southern Free State, South Africa, for the placement of abdominal radio transmitters. Five combinations of ketamine hydrochloride with xylazine hydrochloride, midazolam or medetomidine hydrochloride were used to induce anaesthesia. In some cases the level of anaesthesia was maintained with 1.5 % halothane. A mixture of ketamine hydrochloride and medetomidine hydrochloride was found to be most effective. Atipamizole reversed the affects of medetomidine hydrochloride, resulting in a smooth and full recovery within 8 minutes. The immobilisation and subsequent anaesthesia of these animals on cold winter nights resulted in hypothermia, and keeping the animals warm was essential to the success of the procedures undertaken. Reversal of the sedative medetomidine hydrochloride proved to be important, because animals that were released before they were fully conscious took refuge in their burrows so that care was impossible

CHEMICAL IMMOBILIZATION AND ANESTHESIA OF FREE-LIVING AARDVARKS (ORYCTEROPUS AFER) WITH KETAMINE-MEDETOMIDINE-MIDAZOLAM AND ISOFLURANE

“…The induction time was similar to that observed in captive aardvarks given ketamine in combination with detomidine (Vodicka 2004) and in wild but restrained aardvarks given ketamine in combination with medetomidine or xylazine (Nel et al 2000). The addition of midazolam did not appear to shorten the time to recumbency.…”

“…Hypertension has been observed in other species given the same combination of drugs (Curro et al 2004;Ebner et al 2007;Schernthaner et al 2011) and is attributed mainly to the effects of medetomidine on the peripheral vasculature. Bradycardia, which has been observed in aardvarks (Nel et al 2000;Langan 2008), could also be attributed to the alpha-2 agonists cardiovascular effects, primarily as a secondary effect of druginduced vasoconstriction, but it may also reflect the animal's naturally low metabolic rate (McNab 1979).…”

“…The major risk of remote injection is losing contact with a darted aardvark, which may have dire consequences if an aardvark is exposed to predators or if it lies in an awkward position, particularly in a burrow, which may result in respiratory compromise (Nel et al 2000). By immobilizing aardvarks when they were actively foraging, most became recumbent on the ground surface.…”

“…Aardvark capture techniques include hand capture, setting funnel traps at burrow entrances, and netting, followed by intramuscular (IM) injection of immobilizing agents (van Aarde et al 1992;Nel et al 2000). It is possible that these methods of capture elicit a severe stress response as mortalities have been reported (Taylor and Skinner 2003).…”

“…For trapped and restrained wild aardvarks, ketamine has also been used with medetomidine, midazolam, or xylazine with various levels of success (van Aarde et al 1992;Nel et al 2000), with the combination of ketamine and medetomidine being the most effective.…”