Traveling with pets often proves to be a challenging and stressful experience for both humans and their companions. A number of U.S. airlines -- including American, Delta and United -- offer customers the option to check their pets on a plane, but in the interest of safety, there are a number of boxes the humans must check before booking their furry friends a spot in the cargo hold.
Flying animals on U.S. commercial airliners is generally safe. The U.S. Department of Transportation reported less than one incident per 10,000 animals transported via air in 2016. DOT defines an incident as the injury, death or loss of an animal during air transportation. For the purpose of these statistics, DOT defines an "animal" as any pet in a U.S. family household or any dog or cat shipped as part of a commercial shipment on a scheduled passenger flight.
The rabbit survived the trip, according to the airline, but died sometime after being unloaded from the plane. The airline offered to conduct a necropsy but the owner declined. The cause of death is unclear. United said in a statement that it was "saddened" by the news and is reviewing the incident.
The Animal Welfare Act, first signed into law in 1966 and amended at least eight times since, enforced by the Department of Agriculture, dictates the rules the owner and the airlines must respect.
Dogs and cats must be at least 8 weeks old, and those younger than 16 weeks traveling for more than 12 hours must be provided food and water. Older animals must be fed at least every 24 hours and water at least every 12 hours, and they must be accompanied by written instructions on how to do so. Rules from the Department of Agriculture also protect animals from being shipped in harmful temperatures.
Along with a veterinarian's stamp of approval for the pet's health, airlines generally require owners to give the pet a kennel large enough for it to stand, turn, sit and lie down in a natural position. Additionally, the kennel must have good ventilation and food and watering dishes.
The strength of the kennel is also critical, as an animal getting loose in the cargo hold could be dangerous, according to DOT.
Animals always fly in pressurized and climate-controlled sections of the cargo hold and are usually kept in designated animal care facilities at major airports, according to DOT.
Airlines typically employ or contract specialists to handle the animals on each end of the flight, including loading the animals last and removing them first from the airplane.
A spokesperson for DOT did not answer ABC News' request for more data prior to 2016 or whether the reporting method has changed since 2012.