Pharmacologic effects of epidural versus intramuscular administration of detomidine in cattle

Objectives-To determine whether epidural administration of detomidine hydro chloride to cattle induced analgesia of the perineum and to compare analges ic and systemic effects of epidural versus IM administration of detomidine at a dose of 40 mu g/kg in cattle. Animals-18 healthy adult cows. Procedure-6 cows were given detomidine by epidural administration, 6 were g iven detomidine IM, and 6 (control group) were not given detomidine. Analge sia was assessed by determining responses to needle pinpricks in the perine um and flank and by applying electrical stimuli to the perineum and flank a nd determining the voltage that induced an avoidance response. Degree of se dation and ataxia were scored, and mean arterial pressure, heart rate, resp iratory rate, and frequency of ruminal contractions were measured. Results-Epidural and IM administration of detomidine induced comparable deg rees of analgesia of the perineum and flank, accompanied by moderate sedati on and ataxia, hypertension, cardiorespiratory depression, and rumen hypomo tility. Conclusions and Clinical Relevance-Epidural and IM administration of detomi dine at a dose of 40 mu g/kg induced similar analgesic and systemic effects in cattle. Epidural administration of detomidine did not appear to be adva ntageous over IM administration.