Hi:
I checked a couple of airlines out of Washington Dulles Airport. I looks like Delta may take your dog in their cllimate controlled baggage bays. I could not find any restrictions on dog bread. I would go on their web site and take a look than call a rep from Delta to confirm the info before making a reservation. I also looked at American Airlines but they restricted flying certain breads which included yours. Good luck.
Steve
Is that a direct flight or do they change planes in Atlanta?