Anesthesia of Donkeys and Mules

The domestic horse, Equus caballus , and the domestic donkey, Equus asinus , share a common ancestor but are now morphologically distinct species. The anatomy and physiology of the horse airway have been studied extensively to better understand respiratory diseases of horses. Differences in metabolism of glucose and glycogen in response to work and stress have been documented between donkeys and horses. Differences exist in some laboratory values between donkeys and horses. The drugs used for sedation in horses can be used in donkeys and mules, but the dose usually has to be higher to achieve the same effect. A donkey's first response to a potential threat to its individual integrity is opposite to the response of a horse. The combination of these different responses makes pain assessment in donkeys more difficult than in horses, even qualitatively.