Representative oxygen dissociation curve and equation for the chicken

Area of Science:

• Physiology
• Avian gas exchange

Background:

• Considerable variability exists in reported oxygen dissociation curves for chickens.
• This variability presents challenges for respiratory physiologists studying avian gas exchange.

Purpose of the Study:

• To establish a representative oxygen dissociation curve for chickens.
• To provide a standard for comparison of experimental avian gas exchange data.

Main Methods:

• Compiled data from eight reported oxygen dissociation curves.
• Adjusted data to standard conditions: temperature (42°C), pH (7.5), and partial pressure of carbon dioxide (40 torr).
• Determined the mean oxygen partial pressure (PO2) versus percent hemoglobin saturation curve and fitted it to an equation.

Main Results:

• The mean P50 value for literature data was 47.4 ± 9.8 Torr.
• The derived equation yielded a P50 value of 45.3 Torr.
• A representative curve with standard deviations was generated, along with a computational equation.

Conclusions:

• The developed mean curve serves as a representative standard for chicken oxygen dissociation.
• The derived equation allows for rapid computation of percent oxyhemoglobin saturation given PO2 under standard conditions.