Volume and ventilation of air sacs in ducks studied by inert gas wash-out.
D000400:Air Sacs / Q000502:physiology*; D000818:Animals; D004372:Ducks / Q000502:physiology*; D006371:Helium; D007700:Kinetics; D013058:Mass Spectrometry; D008954:Models, Biological; D012119:Respiration; D012121:Respiration, Artificial
D006371:Helium