Flirty, a miniature horse service animal, in the spotlight after working American Airlines flight

Passengers on an American Airlines flight from Chicago to Omaha on Aug. 29 had a unique in-flight neighbor: a miniature horse working as a service animal.

That's because the U.S. Department of Transportation included miniature horses among its approved service animals in its guidance on the subject issued earlier this month.

The AASTEWS Instagram account, which documents "the lifestyle and travels of American Airlines flight attendants, one layover at a time" featured video of the miniature horse walking through the Nebraska airport after landing.

The horse, named Flirty, was working as a service animal for a passenger on the E175 regional jet.

The Instagram account's stories also featured a picture of the horse with the AA crew, and the account called out Flirty's Instgram account, which had additional documentation of Flirty's flight experience. One post on Flirty's account notes that the miniature horse came just to the edge of the seat: "If she were any bigger and we would need 3 seats to accommodate her!"

Though the Americans with Disabilities Act generally recognizes only dogs as service animals, it was revised in 2010 to include trained miniature horses under some circumstances. According to the Department of Justice, a miniature horse measures "24 inches to 34 inches to the shoulders and generally weighs between 70 and 100 pounds."

Some members of the ADA community prefer miniature horses to dogs as service animals because they live longer, reducing the frequency of training and bonding with a new companion. This month, the Department of Transportation included miniature horses among its list of commonly accepted service animals.

By definition, service animals are different than emotional support animals and are treated differently by airlines. A service animal is trained to help a person who has a disability, such as a visual impairment. Emotional support animals provide comfort or therapeutic companionship.

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A passenger traveling with a trained service animal does not need to provide documentation to travel with the animal or give advanced notice (though it is recommended). Those traveling with emotional support animals must do both.

American Airlines updated its policies for emotional support animals on April 1 to limit emotional support animals to dogs, cats and miniature horses.

"The miniature horse was a trained service animal, which American Airlines accepts onboard following evaluation on a case-by-case basis," American Airlines spokeswoman Martha Thomas told USA TODAY. "We recognize the important role trained service dogs, cats and miniature horses can play in lives of those with disabilities."

Owners must make a reservation with the Special Assistance Desk 48 hours in advance and provide documentation, including a veterinary form showing immunizations, a form from a mental-health professional, a behavior-guidelines form and an animal-sanitation form if the flight is longer than eight hours.

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The airline validates the documentation by contacting the mental-health professional, and there is a limit of one animal per person.

Contributing: David Oliver, Julia Thompson

This article originally appeared on Arizona Republic: Miniature horse works as service animal on American Airlines flight