Other names Mammoth Jack (males) Scientific name Equus asinus Rank Breed | Country of origin United States Higher classification Donkey | |
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Similar Poitou donkey, Zamorano‑Leonés, Catalan donkey, Andalusian donkey, Grand Noir du Berry | ||
Gaited mammoth jack in slow motion
The American mammoth donkey, commonly known as the mammoth jack, American mammoth or American mammoth jack, is a landrace of North American donkey, descended from multiple breeds of donkey imported to the United States. George Washington, with Henry Clay and others, bred for an ass that could be used to produce strong work mules. Washington was offering his jacks for stud service by 1788. Large breeds of asses were found in Kentucky by 1800.
Breeds that influenced the mammoth jack include the Maltese donkey, Poitou donkey (also sometimes called the mammoth donkey), Andalusian donkey, Majorcan donkey and Catalan donkeys. Males, called jacks, must be at least 14 hands (56 inches, 142 cm) and females, called jennies or jennets must be at least 13.2 hands (54 inches, 137 cm).
Purebred and pedigreed specimens of the variety that conform to a published standard of characteristics are considered a formal breed, registered with the American Mammoth Jackstock Registry, commonly called by various names including American Mammoth Jackstock, Mammoth Jack stock and Mammoth Jack. These breed designations may encompass females.
The largest living mammoth donkey, at 17 hands (68 inches, 173 cm), resides in Waxahachie, Texas.
