Aortic pulse-wave velocity in chickens and ducks

Area of Science:

• Cardiovascular Physiology
• Comparative Anatomy
• Biomechanics

Background:

• Previous research suggested birds have inelastic arteries and high aortic pulse-wave velocity.
• Understanding avian arterial mechanics is crucial for comparative physiology.

Purpose of the Study:

• To determine the pressure-radius and pressure-volume relationships of avian thoracic and abdominal aorta segments.
• To calculate aortic pulse-wave velocities in chickens and mallards and compare them to mammals and turkeys.

Main Methods:

• Ex vivo pressure-volume and pressure-radius analyses of thoracic and abdominal aortic segments from chickens and mallards.
• Segments were pressurized to 300 mm Hg using saline infusion at a constant flow rate.
• Pulse-wave velocities were calculated from pressure-volume curves within the physiological pressure range.

Main Results:

• Thoracic aortic segments exhibited sigmoidal pressure-volume curves with highest compliance in the physiological range.
• Abdominal aortic segments were less compliant than thoracic segments.
• Calculated pulse-wave velocities (6-10 m/sec) for chickens and mallards were similar to mammals and published values for turkeys (8-12 m/sec).

Conclusions:

• Avian thoracic aortas demonstrate significant compliance, particularly at physiological pressures.
• Aortic pulse-wave velocities in birds are comparable to those found in mammals.
• This study refines our understanding of avian arterial biomechanics and cardiovascular function.