Anaesthetic effects of xylazine/ketamine combination in New Zealand white rabbit

Abstract

The anaesthetic effects of xylazine/ketamine drug combination was studied using New-Zealand white (NZW) rabbits. The animals were grouped into three as follows; Group A (Control) animals were pre-medicated with 5mg/kg xylazine (X) intramuscularly (i/m), followed 10 minutes later with 35mg/kg Ketamine(K) i/m .Group B animals were induced with a combination of xylazine/ketamine (XK) followed by a single incremental xylazine at a dose rate of 1.7 mg/kg administered at the time of loss of surgical analgesia. Group C animals were also induced using XK as in control group but incremental XK, 1.75mg/kg and 11.7mg/kg respectively administered as a single injection following onset of pain at the operating site. The result of the study indicate that the onset of anaesthesia marked by loss of righting reflex differ but not significantly (P >0.05) among the three groups. Duration of surgical analgesia lasted significantly (P <0.05) longer (59.1 ±25.1 minutes) in XK (control) group compared to xylazine/ketamine plus xylazine (XKX/Group B) and xylazine/ketamine plus xylazine/ketamine (XKXK/Group C). There was no morbidity or mortality or salivation in any of the animals even when atropine was not used as a premedicant. There were reductions in heart rate and respiratory rate in the three groups but rectal temperature was normal throughout the period of surgery. It was concluded that xylazine/ketamine combination provides a safe anaesthetic option for surgery in NZW rabbits. However, its induced duration of analgesia varies among individuals of this specie studied thus necessitating incremental dosing using either xylazine or a combination of xylazine/ketamine for surgeries lasting up to 70 minutes.

Keywords: anaesthetic, xylazine, ketamine, New Zealand, rabbits

Tropical Veterinarian Vol. 22(3&4) 2004: 106-112