I worked at FedEx for 10months. And the trucks i loaded constantly delivered to pet-stores, and a lot of times reptiles and fish would come through to home delivery.
The amount of packages ive seen thrown, tossed, kicked, flung etc that had the "warning live animals" was disturbing
Yep, That's why it's up to the shipper to package the animal as securely as possible. No matter what you write on the package, fedex and any other shipping company does not care and will not treat your package any differently than any other package.