title: Hen's eggs with retarded gas exchange. I. Chorioallantoic capillary growth.
abstract: The diffusing capacity of the hen's egg for carbon monoxide (D tau co) increases during incubation, reflecting the development of the chorioallantoic circulation. Previous work showed that the increase in D tau co could be diminished by incubating eggs in a 60% oxygen environment. The present work explored the effects of impeding gas exchange on the development of D tau co. Half the shell area was covered during incubation by a removable neoprene membrane which limited D tau co by approximately 20%. No difference could be detected between the D tau co values (measured with the membrane removed) of these eggs and control eggs incubated in the same 21% oxygen environment without a neoprene membrane. We conclude that the development of the chorioallantoic circulation is at its maximum under normal conditions of incubation and cannot be accelerated by restricting gas exchange.
mesh_terms: D000482:Allantois / Q000098:blood supply*; D000818:Animals; D002196:Capillaries / Q000502:physiology*; D002248:Carbon Monoxide / Q000378:metabolism*; D002642:Chick Embryo; D002823:Chorion / Q000098:blood supply*; D004058:Diffusion; D004528:Egg Shell; D005321:Extraembryonic Membranes / Q000098:blood supply*; D000860:Hypoxia
chemical_list: D002248:Carbon Monoxide