Respiratory exchanges in the incubated egg of the domestic guinea fowl.
The daily O2 uptake (MO2) and CO2 production (MCO2) rates were measured in guinea fowl eggs with a wide range of mass specific shell water vapor conductance, spGH2O [0.108 to 0.365 mg.(g.Torr.day)-1], from day 10 to the end of incubation, day 28. The respiration rate showed a plateau, from day 22 to day 24, typical of a precocial bird: MO2 approximately 21.4 and MCO2 approximately 15.2 mmol.day-1. The plateau MO2 value was that predicted by allometric relation. At the plateau, respiratory exchanges appeared significantly limited by spGH2O. The limiting effect of spGH2O on respiratory metabolism began as soon as day 18 (64% of incubation time). The respiratory ratio was 0.75 at day 10, decreased to 0.65-0.66 on days 12-14 and stabilized at 0.70-0.71 on days 20-28.
Ancel
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A
Centre d'Ecologie et Physiologie Energétiques, (ex Laboratoire d'Etude des Régulations Physiologiques), Centre National de la Recherche Scientifique, Strasbourg, France.
Visschedijk
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AH
D000367:Age Factors; D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D008433:Mathematics; D010063:Ovum / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism; D011200:Poultry / Q000502:physiology*; D011659:Pulmonary Gas Exchange / Q000502:physiology*
D002245:Carbon Dioxide; D010100:Oxygen