7-30. 許多呼吸性疾病在感染初期，眼膜處的眼角膜會有氣泡樣的輕微炎症。圖右的蛋殼問題可能是雞隻感染傳染性支氣管炎所致，較差的禽舍溫度會引發呼吸道的問題。 Many respiratory problems start with a slight inflammation of the eye membrane, which can be recognised by slight foaming in the corner of the eye. The shell defect may be caused by infectieus bronchitis. Breathing problems are worsened by a poor climate.