Abstract
The purpose of this study was to determine the effect of heavy thermal panting on arterial oxygen (Pa O 2 ) and carbon dioxide (Pa CO 2 ) tension in emus. The birds showed no significant change in body temperature during a 3–4 h heat stress caused by increasing ambient air temperature from 21 to 46°C. However, the emus increased their respiratory frequency 10-fold (from 5.3 to 52.9 breaths · min −1). The high respiratory frequency resulted in a slight but significant decrease in Pa CO 2 (from 33.5 to 29.8 mm Hg), coupled with a slight increase in pH (from 7.449 to 7.469). Paradoxically, these changes were accompanied by a significant decrease in the arterial oxygen tension (from 99.7 to 84.6 mm Hg). The arterial hypoxia suggests hypoventilation while the hypocapnia suggests hyperventilation of the lungs. This could result from various spatial and/or temporal changes in ventillation/perfusion ratios.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
