krysia? Did you travel with your dog or did you have it sent "cargo"...by himself?
A dog is allowed in a cabin only if it is under 8 kilo. Mine were in the cargo unit because there were 2 together and they were heavy. Depending what airline you chose, there are different rules. The best one would be LOT or another one that goes direct to US.
Leonbergers are big, so he might have to fly cargo if over 8 kilo.
Is that the one that eats the chickens?
Haha, not only. He ate my rabbits and ducks and rooster and chickens. He's got a big kennel now where he can't get to them. He was fed raw meat as a puppy by the breeder in Poland, something you shouldn't do to a German Shepherd because they have that taste of blood...