FORT WORTH, Texas—Heat might have killed seven puppies that died in the cargo hold of an American Airlines jet this month.
American Airlines spokeswoman Mary Frances Fagan said Tuesday that necropsies on the puppies were inconclusive but found that heat "may have been a factor."
The puppies died soon after the flight from Tulsa, Okla., landed in Chicago on Aug. 3. Cargo handlers in Chicago noticed they were lethargic and took them to a veterinarian's office.
Fagan said the flight complied with company policy that prohibits shipping animals when outside ground temperatures exceed 85 degrees.
The National Weather Service recorded 86 degrees in Tulsa while the plane, which was delayed from taking off for an hour, was still on the ground at 8 a.m. But American relies on temperatures reported by The Weather Channel's website, and Fagan said those readings "at loading, pushback, take-off and arrival" were within the 85-degree limit.
Fagan also said the puppies that died might have had other health problems because 17 other dogs survived the same flight. The seven who died were among 14 puppies put on the plane by a shipper that the airline declined to identify.
American declined to release the necropsy reports on the dead puppies. The airline said it carries more than 100,000 dogs a year.
The puppy deaths outraged animal-rights groups. The Humane Society of the United States and the Animal Legal Defense Fund called on government officials to investigate whether the airline violated federal rules on shipping animals. In 1994, the U.S. Agriculture Department fined
The U.S. Transportation Department said last month that 122 dogs have died while being shipped on planes since May 2005, when airlines were first required to disclose the deaths. Animal-rights groups say the numbers vastly understate the problem because airlines only report pets that are killed or lost -- not animals shipped by breeders, as appeared to be the case on American.
Last week three U.S. senators asked the Transportation Department to require airlines to report all deaths of dogs and cats, including those shipped by breeders and handlers.
The American Society for the Prevention of Cruelty to Animals recommends that owners avoid shipping pets in the cargo hold. Most airlines, however, will only allow pets in the passenger cabin if they are small enough to fit in a carrier under a seat.