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Updated: Jul 16, 2026
09:32
Evaluation of Auditory Brainstem Response in Chicken Hatchlings
Published on: April 1, 2022
Development of avian intrapulmonary chemoreceptors
Jason Q Pilarski1, Steven C Hempleman
1Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona 86011-5640, USA. jqp2@dana.ucc.nau.edu
Respiratory Physiology & Neurobiology
|March 3, 2007
Summary
Avian intrapulmonary chemoreceptors (IPC) sense CO(2) before hatching. Postnatal development shows maturation in tonic CO(2) sensitivity, while phasic sensitivity is fully developed early.
Area of Science:
- Physiology
- Developmental Biology
- Respiratory System
Background:
- Avian intrapulmonary chemoreceptors (IPC) are crucial for respiratory control.
- The developmental maturation of IPC CO(2) sensitivity remains largely uncharacterized.
- Understanding IPC development is key to understanding respiratory regulation in young birds.
Purpose of the Study:
- To determine if avian IPC can sense CO(2) during early development.
- To investigate the developmental trajectory of IPC CO(2) sensitivity from pre-hatching to postnatal stages.
- To compare the CO(2) sensitivity of developing IPC with that of adult birds.
Main Methods:
- Single IPCs from Anas platyrhynchos ducklings were recorded starting 6 hours before internal pipping through 4 days post-hatching.
- IPC discharge characteristics were analyzed during development and compared to adult ducks (>12 weeks old).
- CO(2) sensitivity was assessed by recording IPC responses to rapid step changes in CO(2).
Main Results:
- IPC demonstrated CO(2) sensitivity prior to hatching, during the paranatal period.
- Developing IPC exhibited higher peak discharge frequencies and greater spike frequency adaptation compared to adults.
- Tonic CO(2) sensitivity in developing IPC was significantly lower than in adult ducks (P<0.05).
Conclusions:
- Phasic CO(2) sensitivity of avian IPC is established before hatching.
- Tonic CO(2) sensitivity undergoes postnatal maturation, potentially linked to the hatching process.
- The mechanisms governing phasic and tonic IPC responses may be distinct and follow different developmental paths.
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