New air travel rules could mean that pot-bellied pigs, miniature horses and monkeys could all be allowed to travel on planes if they offer passengers "emotional support".
The guidelines drawn up by the Department of Transportation are part of a draft manual on equality for disabled people travelling on commercial flights, according to the Daily Mail.
Transportation officers will use the guide to determine whether a passenger needs to be accompanied by the animal.
According to cnsnews.com, the manual provides a hypothetical scenario that runs like this: "A passenger arrives at the gate accompanied by a pot-bellied pig. She claims that the pot-bellied pig is her service animal. What should you do?"
"Generally, you must permit a passenger with a disability to be accompanied by a service animal.
"However, if you have a reasonable basis for questioning whether the animal is a service animal, you may ask for some verification."
The manual adds: "If you determine that the pot-bellied pig is a service animal, you must permit the service animal to accompany the passenger to her seat provided the animal does not obstruct the aisle or present any safety issues and the animal is behaving appropriately in a public."
ABC News reported that last November a 300lb pot-bellied pig flew on a US Airways flight from Philadelphia to Seattle as it was deemed as being a therapeutic pet.
The manual also describes miniature horses and monkeys, as "commonly used service animals", but that US airlines "are not required to carry certain unusual service animals in the aircraft cabin such as ferrets, rodents, spiders, snakes and other reptiles".
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