Pentobarbital is a short-acting anesthetic that in subanesthetic doses (2 mg/kg, IV) causes moderate sedation for about 30 minutes in adult cows without causing recumbency, although mild-to-moderate ataxia is observed (Valverde et al., 1989). The effects of this dose on arterial blood gases, respiratory rate, heart rate, blood pressure, and rumen motility is minimal. Similar effects have been observed in calves using the same dose.