The July, 2018 Airline Pet Travel Report contains pet incidents for the month of May, 2018.
American Airlines had a death this month on a flight from Dallas Ft. Worth, TX to Ontario, CA where a 14 year old labrador retriever arrived unresponsive with evidence of possibly being deceased. This dog was one of three animals transported on this flight. In Dallas, prior to the flight departing, the dog was having difficulty breathing, as if it were hyperventilating. The crew chief escorted the owner to the dog, where it was comforted and given water. The owner allowed the crew chief to load the pet on the aircraft.
Delta had two injuries and one death this month. The cause of both injuries were self-inflicted and the cause of death is unknown.
Source: July 2018 Air Travel Consumer Report.