Comparative evaluation of ropivacaine, bupivacaine and xylazine-ketamine combination for epidural analgesia in goats

The study was conducted on eighteen healthy non-descript male goats divided into 3 groups: A, B and C, having 6 animals in each. Lumbosacral epidural ropivacaine (0.6 mg/kg), bupivacaine (0.5 mg/kg) and xylazine and ketamine (0.025 mg/kg and 2.5 mg/kg) were administered in groups A, B and C, respectively. The treatments were compared using clinical, physiological, haematological, biochemical and acid base/blood gas parameters. The earliest onset of analgesia was produced by epidural xylazine and ketamine combination. Xylazine and ketamine, bupivacaine and ropivacaine produced complete analgesia of the tail, perineum, inguinal region and thighs for variable intervals. The xylazine and ketamine combination produced analgesia of a greater extent and longer duration, followed by bupivacaine and ropivacaine. Mild sedation was produced by the xylazine and ketamine combination alone. Recovery was faster with ropivacaine, followed by bupivacaine and the xylazine and ketamine combination. The xylazine and ketamine combination produced a non-significant decrease in the heart rate and respiratory rate of the animals. There were insignificant fluctuations in pCO(2), pO(2), SO2, pH and HCO-(3) values from base line at different intervals in all the groups. The changes in haematobiochemical and blood electrolyte values were transient, and hence of little significance in all the groups. The results of this study suggest that all these drugs could be considered safe for epidural analgesia in the administered doses for healthy goats.