Anaesthesia was induced with alfaxalone to effect -LSB- @ mgkg ( -@ ) intravenously ( IV ) every @seconds -RSB- , initially maintained with @mgkg ( -@ ) hour ( -@ ) alfaxalone IV and infusion adjusted ( @ mg kg ( -@ ) hour ( -@ ) ) every five minutes according to alterations in heart rate ( HR ) , respiratory rate ( fR ) , Doppler blood pressure ( DBP ) and presence of palpebral reflex .