My Red boy, Congo, had an awesome BAROO! We were so happy to hear it every time! He couldn't do it enough for my amusement! I don't remember at what age the BAROO's stopped but I'm thinking 14 or 15. When he was in his prime, I think he yodeled at least once a week.
Bandit, my 7 year old tri girl, has never BAROOED in her life! She purrs like a cat and cries like a newborn baby, but never a yodel.
Hunter, my 2 year old BRAT tri, has a great yodel. His voice usually cracks mid-yodel. Almost like he was a heavy smoker at some point in his short life! He also had the loudest yawn on the planet!:)