Twenty eight mature donkeys subjected to elective surgery were randomly assigned to four groups of 7 donkeys. After premedication with 80 µg/kg of romifidine and 0.4 mg/kg of diazepam administered intravenously anesthesia was induced either with 5 mg/kg IV thiopental sodium (group I), 2.2 mg/kg IV ketamine (group II), 3 mg/kg IV propofol (group III) or 5g/50kg IV chloral hydrate (group IV). Anesthesia was maintained with continuous intravenous infusion using a mixture of 1 g thiopental/25 g guaifenesin/30 mg romifidine in 500 ml 5% dextrose (group 1), 500 mg ketamine/25 g guaifenesin/30 mg romifidine in 500 ml 5% dextrose (group II), 400 mg propofol/25 g guaifenesin/30 mg romifidine in 500 ml 5% dextrose (group III) or 25g chloral hydrate, 25 g guaifenesin/30 mg romifidine in 500ml 5% dextrose (group IV). The anaesthetic and cardiorespiratory responses to the four injectable anaesthetic combinations are reported. The results indicated that the four anaesthetic combi- nations could be used as a safe method of total intravenous anesthesia for short and prolonged surgical procedures under field conditions in donkeys.