Ah. You are correct sir/madam, my mistake. My experience is with Delta - now I see it differs with each particular airline. Found an interesting site:

http://serendipityairedales.tripod.com/FLYdogs.html

IMHO I would be hesitant to fly a non-service dog in baggage if I didn't have to anyway. I transported a blood-donor dog from SAN-EWR in baggage (no option due to his size) and let me tell you the dog was definitely stressed and messed when he landed. Really, what is a blind person going to do with a stressed out and soiled seeing eye dog at the airport when they land?

Wonder what the ground temps were on the offending flight?