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Acepromazine produces mild tranquilization without analgesia in animal species. It produces a calming effect by blocking dopaminergic receptors at the basal ganglia in the brain [3]. The drug has minimal effects on heart rate and respiratory function. Direct depression on myocardial contractility and a decrease in cardiac output with subsequent hypotension often observed with the administration of acepromazine are the result of its effect on blocking α₁ adrenoceptors located at the myocardium [4, 5]. In addition to a calming effect, acepromazine produces beneficial effects such as antiarrhythmic and antiemetic effects. Acepromazine may cause relaxation of the esophagus and cardia, which increases the risk of regurgitation in ruminants [6, 7]. Thus, special measures to protect the airway should be taken if the animal is to be placed in lateral or dorsal recumbency during the procedure. Use of the coccygeal vein for intravenous (IV) injection should be avoided when administering acepromazine because of its close proximity to the coccygeal artery [3]. Prolapse of the penis with potential subsequent trauma following the administration of acepromazine as reported in horses may occur in ruminants as well. The IV and intramuscular (IM) doses of acepromazine recommended for ruminants are 0.01–0.02 and 0.03–0.1 mg/kg, respectively [8]. The duration of tranquilization of acepromazine is usually 2–4 hours when administered at recommended dosages, but effects of 4–8 hours have been reported [9]. The use of acepromazine is contraindicated in debilitated or hypovolemic animals due to its hypotensive effect [3]. In addition, acepromazine depresses the thermoregulatory center, resulting in significant hypothermia and prolonged recovery in anesthetized newborns and neonatal animals. Acepromazine (0.03 mg/kg IM) has been administered occasionally to calm fractious bulls prior to induction of anesthesia with IV xylazine and ketamine.