Changes

*Severe respiratory distress with laboured breathing and grunting on expiration

*Severe respiratory distress with laboured breathing and grunting on expiration

*Can result in [[Diffuse Fibrosing Alveolitis|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 [[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

*Their loss allows massive flooding of the alveoli with a protein-rich fluid

*Their loss allows massive flooding of the alveoli with a protein-rich fluid

*Commonly found post mortem

*Commonly found post mortem

*Can be a consequence of:  

*Can be a consequence of:  

# [[Lungs Circulatory - Pathology#Embolism, thrombosis and infarction|'''Septic emboli''']] lodging in the pulmonary vessels

# [[Pulmonary Embolism, Thrombosis and Infarction|'''Septic emboli''']] lodging in the pulmonary vessels

# '''Extension''' from severe focal suppurative [[Lungs Inflammatory - Pathology#Bronchopneumonia|bronchopneumonia]]

# '''Extension''' from severe focal suppurative [[Lungs Inflammatory - Pathology#Bronchopneumonia|bronchopneumonia]]

# '''Aspiration''' of foreign material (see [[Lungs Inflammatory - Pathology#Aspiration pneumonia|aspiration pneumonia]])

# '''Aspiration''' of foreign material (see [[Lungs Inflammatory - Pathology#Aspiration pneumonia|aspiration pneumonia]])

===Uraemic pneumonia===

===Uraemic pneumonia===

*Severe uraemia causes increased permeability of the blood-air barrier and therefore can cause [[Lungs Circulatory - Pathology#Pulmonary oedema|pulmonary oedema]]

*Severe uraemia causes increased permeability of the blood-air barrier and therefore can cause [[Pulmonary Oedema|pulmonary oedema]]

*In addition to the oedema, there may also be degeneration and calcification of smooth muscle and connective tissue fibres

*In addition to the oedema, there may also be degeneration and calcification of smooth muscle and connective tissue fibres

*Lungs do not collapse on opening the thorax in severe cases

*Lungs do not collapse on opening the thorax in severe cases