Butter is the name given to the rescue donkey specimens spread in the southwestern states of the USA, where they were introduced from the Spanish colonizers from the 15th century (butter, in fact, is the Spanish word for "donkey" today also non-Hispanics use it to designate the donkey in these states.)
The wild "burros" therefore descend from those who escaped, abandoned or freed intentionally; Their number grew steadily during the California Caliph Race when thousands of people who did not make a fortune left their own animal.
Since 1971, US law protects these rescued donkeys, as well as mustangs, entrusting selected bodies of people to cure groups in distress or danger.
They are very distrustful animals, and at the same time very curious: they can be tame with great patience, but tend to be unlovely at work.
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