The purpose of this study was to compare the efficacy of various external heating devices in maintaining body temperature in anesthetized rabbits (Oryctolagus cuniculus). Rabbits were divided into 3 groups and placed on either no heating device, a circulating warm-water blanket, or a forced-air warming device. The animals underwent identical surgical procedures unrelated to the scope of the study, and body temperatures were monitored at 5-min intervals for a 45-min period. Results showed that rabbits had a statistically significant loss of body temperature during the procedure when no heating device was used, no significant loss in body temperature with the use of the forced air-warming device, and a minor increase in body temperature with the use of the circulating warm-water blanket. This study shows that external heating devices are necessary for maintenance of normal body temperature in rabbits under general anesthesia, and forced-air warming devices and circulating warm-water blankets are effective heating devices.