Pigeon-breeder's lung disease, also called bird fanciers lung, is a hypersensitivity pneumonitis (see this term) induced by inhalation of bird derived-proteins. Presentation can be acute with chills, cough, fever, shortness of breath, chest tightness usually resolving within 24 h after cessation of antigen exposure, sub-acute with cough and dyspnea over several days to weeks, whereas chronic form results in breathlessness, coughing, lack of appetite and weight loss.