Question

do birds have vascular air sacs in their lungs ?

Answer 1

yes......they have air sacs

Air sacs have very thin walls with few blood vessels. So, they do not play a direct role in gas exchange. Rather, they act as a 'bellows' to ventilate the lungs (Powell 2000). Air sacs and axial pneumatization in an extant avian.....

Answer 2

Yes sure.... Birds have that in their lungs