1 The bitch has been pushing hard for an hour with no results. 2  A puppy presents rear end first and the head is too large to clear the pelvic bones.  There has been more than two hours between births, but you can still feel puppies inside.
Bronchus / Bronchi / Bronchioles. The airways of the lungs. When a person takes in a breath of air, the air travels through the nose or mouth, into the larynx, then into the trachea, which is the main passageway into the lungs. The trachea divides into a right and left main bronchus.
Air travels to and from the lungs though two branches of the trachea called bronchi (one branch equals bronchus; 2 is bronchi). The bronchi subdivide within the lobes of the l â¦ ungs into smaller and smaller air vessels called bronchioles or bronchioli (singular), that terminate in alveoli.