- Caused by Staphylococcus aureus
- Occurs in horses and pigs usually due to wounds
- Lowgrade persistent infection -> granulomatous lesions
- Grossly:
- Hard nodules with fibrous capsule in muscles
- Contain yellow-brown pus and granules
- Histologically:
- Encapsulated granulomatous lesions
- Central club colonies
- Staphylococci are present
- Granulomatous dermatitis caused by nonfilamentous bacteria
- Usually Staphylococcus aureus
- Small, yellow granules are formed - sulfur granules
- Central bacteria surrounded by homogeneous eosinophilic material
- Filamentous bacteria can also cause granulomas