Anaesthesia of nyala (Tragelaphus angasi) with a combination of thiafentanil (A3080), medetomidine and ketamine

Abstract

A combination of thiafentanil (A3080), medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) was evaluated in 19 boma-habituated (12 female and 7 males) and 9 free-ranging nyala (7 male and 2 females) (Tragelaphus angasi) to develop a safe and reliable anaesthesia protocol. Wide dosages were used safely during this study with ranges for A3080 of 45 + 8 mg/kg with MED of 69 + 19 mg/kg and KET of 3.7 + 1.0 mg/kg (200 mg/ animal). The dosages developed on boma-habituated nyala proved to be equally effective in 9 adult free-ranging nyala (7 males and 2 females). The optimum dosage for nyala was a combination of A3080 (40-50 mg/kg), MED (60-80 mg/kg) plus 200 mg of KET/animal. The anaesthesia was characterised by a short induction, good muscle relaxation and mild hypoxaemia during monitoring the anaesthesia was rapidly and completely reversed by naltrexone hydrochloride (30mg/mgof A3080) and atipamezole hydrochloride (5mg/mg of MED) given intramuscularly. There was no mortality or morbidity associated with this protocol.