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May 11, 2009

About the Breed: American Mammoth Jackstock

As it's name suggests, this breed is a very large donkey, developed in the United States. They are also sometimes refered to as Mammoth Jackstock or Mammoth donkeys.

The American Mammoth Jackstock breed is the largest size of donkey in the United States. Jacks must be at least 58" tall and jennets 56" tall to be registered in the American Mammoth Jackstock Registry. The American Donkey & Mule Society recognises jacks of 56" and jennets of 54" and up as Mammoths in their registry.


Originally, Mammoth Jackstock donkeys were bred to be heavy boned, tall and drafty. In the early days, they were typically black or sorrel in color.

In more recent years there has been a second style of Mammoth donkey that has also become quite popular. They tend to be lighter boned, and more of a saddle type of donkey. These finer boned mammoths would not have met the breed standards in the early days when heavy draft animals were most desired, but now days with the demand growing for donkeys as saddle mounts, these tall lighter boned animals are becoming much more common.

You will also find that nowadays Mammoth donkeys come in all donkey colors including spotted and grey-dun. While these donkeys meet the size requirements, their colors show more recent influance from "standard donkey" blood, as these colors were not seen in the original American Mammoth Jackstock.


The American Mammoth Jackstock breed was the result of crossing several breeds imported from Europe, as well as native donkeys. In 1785, General George Washington was given a Catalan jack and two jennets by the Charles IV, King of Spain. These were some of the early imports used in the development of the breed. Other imported breeds used in the development of the American Mammoth Jackstock were the Malteses, Majorcan, Andalusian, and Baudet du Poitou.

The American Mammoth Jackstock breed was specially developed to be used in siring mules of high quality, strength and size - thus the reason they were selectively bred to be heavy drafty built, and their originally colors of black and sorrel to match the Belgian and Perchron horses they were typically bred to. The resulting mules were an integral part of industry in the years before tracters and machinery were readily available. These mules were used in farming, transportation, the US military, and almost anywhere you would think of using an automobile or heavy machinery today. After the invention of tractors and automobiles, the Mammoth Jackstock breed's numbers declined dramatically as they were no longer in high demand for use in mule production.


The breed is now making a come-back, as breeders work to preserve this awesome breed, and people rediscover their wonderful qualities and quiet dispositions. Now days these large donkeys are mainly used for pleasure. They make excellent riding, driving and pack animals, and are very loyal partners. They are very versitile. You may find them competing at shows, out on quiet trail rides, pulling carts and wagons, and occationally still helping pull a plow or logs on a country farm. With their quite disposition and surefootedness, they make excellent trail riding mounts. Mammoth jacks are also still used in the production of mules.

Ways the American Mammoth Jackstock donkey is being used today:

- Theropy Riding
- Trail Riding
- Gaming Shows
- Pleasure Riding
- Pleasure Driving
- Team Driving
- Quiet Riding Mount
- Companion Animal

Kristie Jorgensen

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Posted by Kristie Jorgensen at May 11, 2009 10:52 PM