Evaluation the sedative and analgesic effect of xylazine and chloropromazine alone or as acombination in sheep

Abstract

The aim of this study was to evaluate the sedative and analgesic effect of xylazine or chloropromazine alone or as a combination quantitively and qualitatively in sheep. Xylazine at (0.05, 0.1, 0.2) mg/ kg i.m. caused sedation in sheep as a dose response manner. Xylazine at 0.2 mg/ kg i.m. was the best dose for deep sedation and recumbency in comparison with 0.05 mg/ kg. Xylazine at 0.1 and 0.2 mg/ kg i.m. caused analgesia at 15 and 30 minute after injection, while 0.05 mg/ kg failed as analgesic dose. Chloroprmazine at 2 and 4 mg/ kg i.m. caused sedation and recumbency in sheep without analgesia. A combination of xylazine and chloropromazine at sedative and not analgesic doses at 0.05 and 4 mg/ kg i.m. respectively significantly decreased the onset of sedation and increased the duration of the safe and deep sedation. As well as caused recumbency, relaxation of skeletal muscles in comparison with control, xylazine, or chloropromazine each alone, and increased the pain threshold of electrical stimulation. So the mixture of xylazine and chloropromazine at sedative (not analgesic) doses is ideal for inducing deep sedation and good analgesia as well as to its skeletal muscle relaxation.