-Chanticleer-
Crowing
She had a respiratory infection the chicken in the video. That’s my chicken it was a while ago and she recovered with antibiotics. It started small and then got like that and then worse. She also had the symptoms of the OP that’s why I asked.Gasping means an abrupt intake of air. You can hear it. Place your ear next to her head as she opens and closes her beak. Do you hear a sudden intake of breath? This is very important. Stress gaping is not of any concern. Gasping due to a pulmonary issue is important. Another type of beak gaping is when a chicken extends the neck when gaping due to discomfort from a crop issue. This needs to be investigated and treated.
The chicken in the above video may be gaping due to discomfort from a crop issue.