Which breed has a specific origin tied to the state of Iowa?

The breed with a specific origin tied to the state of Iowa is the Pony of the Americas. This breed was developed in the 1950s in response to the demand for a smaller, well-rounded pony that could be suitable for children and riders of various experience levels. The Pony of the Americas combines the traits of several horse breeds, particularly those of the Appaloosa, giving it distinctive coloration and patterns. The origin in Iowa is significant because it was here that the breed was first established, particularly focusing on producing a pony with both Appaloosa characteristics and the size suitable for younger riders.

In contrast, the other breeds listed do not have their origins specifically tied to Iowa. The donkey is a domesticated animal with a long history across various regions but not specifically Iowa. The American Saddlebred originates from the United States with ties to Kentucky, while the Spanish Mustang traces its roots to Iberian horses brought to the Americas by Spanish explorers, making its origin more associated with the Southwestern United States and not Iowa. This context highlights the uniqueness of the Pony of the Americas in relation to its state of origin.