Sedative and analgesic effects of intravenous detomidine and tramadol on Horses

This study was performed to evaluate the sedative and analgesic effects of intravenous (IV) administration of detomidine (D) and tramadol (T) to horses. Six warmblood horses each received D (10 ug/kg), T (2mg/kg), and a combination of DT (10 ug/kg and 2mg/kg). No significant differences in the heart rate, respiratory rate, rectal temperature, indirect arterial pressure, and gastrointestinal motility between D and DT were observed. The sedative effect was evident within 5 min after D and DT administration, but no significant difference between D and DT was observed. D and DT induced a similar analgesic effect up to 50 min after injection and DT maintained a longer analgesic effect than D. A significant increase in blood glucose was shown for D after the injection, but not for DT. A horse with T and DT showed an excited behavior within 5 min of the injection. This study suggests that the DT combination could be used for diagnostic procedures and simple surgeries in standing horses, with caution for excitement in the early phase after the administration.