Changes

*Sequel to bronchopneumonia:

*Sequel to bronchopneumonia:

**Mild catarrhal inflammation resolves in 7 days and the lung is back to normal within 3 weeks

**Mild catarrhal inflammation resolves in 7 days and the lung is back to normal within 3 weeks

**More severe inflammation becomes chronic with fibrosis or [[Bronchi and Bronchioles Inflammatory - Pathology#Bronchiectasis|bronchiectasis]]

**More severe inflammation becomes chronic with fibrosis or [[Bronchiectasis|bronchiectasis]]

**[[Lungs Inflammatory - Pathology#Pulmonary abscesses|Abscess]] formation with pyogenic bacteria

**[[Lungs Inflammatory - Pathology#Pulmonary abscesses|Abscess]] formation with pyogenic bacteria

**'''Pleuritis''' in severe fibrinous pneumonia with adhesions

**'''Pleuritis''' in severe fibrinous pneumonia with adhesions

*Associated with a change in pasture (from dry to lush, green)

*Associated with a change in pasture (from dry to lush, green)

*Severe respiratory distress with laboured breathing and grunting on expiration

*Severe respiratory distress with laboured breathing and grunting on expiration

*Can result in [[Bronchi and Bronchioles Inflammatory - Pathology#Diffuse Fibrosing Alveolitis/ Interstitial Pneumonia|diffuse fibrosing alveolitis]]

*Can result in [[Diffuse Fibrosing Alveolitis|diffuse fibrosing alveolitis]]

*Gross appearance is that of enlarged wet lungs, the interlobular septa are markedly widenedith [[Lungs Circulatory - Pathology#Pulmonary oedema|oedema]] and [[Lungs Ventilation - Pathology#Emphysema|emphysema]]

*Gross appearance is that of enlarged wet lungs, the interlobular septa are markedly widenedith [[Lungs Circulatory - Pathology#Pulmonary oedema|oedema]] and [[Lungs Ventilation - Pathology#Emphysema|emphysema]]

*Underlying pathogenesis is ingestion of L-tryptophan in the pasture which is metabolised to 3-methylindole  -> bloodstream -> lungs -> metabolised into a compound toxic to Type 1 pneumonocytes and non-ciliated bronchiolar epithelium

*Underlying pathogenesis is ingestion of L-tryptophan in the pasture which is metabolised to 3-methylindole  -> bloodstream -> lungs -> metabolised into a compound toxic to Type 1 pneumonocytes and non-ciliated bronchiolar epithelium

*Chronic disease of adult cattle occuring sporadically

*Chronic disease of adult cattle occuring sporadically

*Probably caused by repeated subclinical incidents of fog fever or farmer's lung

*Probably caused by repeated subclinical incidents of fog fever or farmer's lung

*[[Bronchi and Bronchioles Inflammatory - Pathology#Extrinsic Allergic Bronchio-alveolitis|'''Farmer's Lung''']]

*[[Extrinsic Allergic Bronchio-Alveolitis|'''Farmer's Lung''']]

**Extrinsic allergic alveolitis

**Extrinsic allergic alveolitis

**Hypersensitivity of ingested or inhaled moulds

**Hypersensitivity of ingested or inhaled moulds

**Parasites passing through the lung as part of their migration e.g. [[Respiratory Parasitic Infections - Pathology#Ascaris suum|''Ascaris suum'']] in the pig, aberrant migration in the case of flukes;

**Parasites passing through the lung as part of their migration e.g. [[Respiratory Parasitic Infections - Pathology#Ascaris suum|''Ascaris suum'']] in the pig, aberrant migration in the case of flukes;

**Parasites for which the lung is the target tissue e.g. [[Respiratory Parasitic Infections - Pathology#Dictyocaulus viviparus|''Dictyocaulus viviparus'']]

**Parasites for which the lung is the target tissue e.g. [[Respiratory Parasitic Infections - Pathology#Dictyocaulus viviparus|''Dictyocaulus viviparus'']]

*Lesions can vary from interstitial to [[Bronchi and Bronchioles Inflammatory - Pathology#Chronic bronchitis|chronic bronchitis]] to [[Lungs Inflammatory - Pathology#Granulomatous pneumonia|granulomatous pneumonia]]

*Lesions can vary from interstitial to [[Bronchitis|chronic bronchitis]] to [[Lungs Inflammatory - Pathology#Granulomatous pneumonia|granulomatous pneumonia]]

*May be infiltrate of eosinophils in pulmonary interstitium and bronchoalveolar spaces

*May be infiltrate of eosinophils in pulmonary interstitium and bronchoalveolar spaces

*[[Lungs Ventilation - Pathology#Atelectasis (Collapse)|Atelectasis]] and [[Lungs Ventilation - Pathology#Emphysema|emphysema]] may result due to obstruction

*[[Lungs Ventilation - Pathology#Atelectasis (Collapse)|Atelectasis]] and [[Lungs Ventilation - Pathology#Emphysema|emphysema]] may result due to obstruction