came to an end with the end of the mining boom and the introduction of railroads in the West. With little value, many animals were turned loose to become the populations of free-roaming burros that inhabit the West today. From about 1785, some large donkeys were imported from Europe to the eastern United States, and were used for the production of mules. In 1888 the American Breeders Association of Jacks and Jennets started a stud-book for these animals under the name American Mammoth Jack. In 1923 it merged with the Standard Jack and Jennet Registry of America, which had been set up in 1908; in 1988 the name was changed to American Mammoth Jackstock Registry. Breeds that may have influenced the mammoth include the Maltese, the Baudet du Poitou, the Andalusian, the Majorcan and the Catalan. In the twentieth century, donkeys came to be more frequently kept as pets in the United States and in other wealthy nations. In 1929 Robert Green of New York imported seven donkeys of the small indigenous Sardinian breed to the United States. The first foal was born in the same year. Although never considered miniature in their country of origin, these animals were soon known as Miniature or Miniature Mediterranean donkeys. Green was a lifelong advocate, and said of them: "Miniature donkeys possess the affectionate nature of a Newfoundland, the resignation of a cow, the durability of a mule, the courage of a tiger, and an intellectual capability only slightly inferior to man's." By 1935 there were 52 of them, and some were sold. Further Sardinian donkeys were imported, as well as similar but quite distinct Sicilian animals. A register of miniature donkeys was started in 1958 by Bea Langfeld, who was the first professional breeder of miniature donkeys in the United States; in 1987 it was merged into that of the American Donkey and Mule Society, which was formed in 1967. Both the Canadian Donkey and Mule Association and the American Donkey and Mule Society register donkeys according to their size, as miniature, standard or mammoth donkeys. These are reported as breeds to the Domestic Animal Diversity database of the Food and Agriculture Organization of the United Nations by the National Animal Germplasm Program of the Agricultural Research Service of the US Department of Agriculture, as are the feral Burro population of the western United States and the Spotted, a color breed. Characteristics