"were looking at factors ranging from heat stroke to carbon monoxide poisoning to pre-existing health problems in connection with a shipment of 14 puppies inside the cargo hold of an American Airlines MD-80 plane from Tulsa … on Tuesday."
A shipment of 14 puppies? I'm willing to bet this was a puppy mill shipment, certainly not a conscientious breeder or someone's own beloved pets. Possibly why the airline's own rules regarding pets in cargo weren't followed?