Changes

**Primary pathogen in various diseases of farm animals

**Primary pathogen in various diseases of farm animals

**Mixed bacterial infections

**Mixed bacterial infections

**Can be secondary to [[Respiratory Viral Infections - Pathology#In Cattle|IBR]]

**Can be secondary to [[Infectious Bovine Rhinotracheitis|IBR]]

**Extracellular haemolysin contributes to infection

**Extracellular haemolysin contributes to infection

**Heat-stable leucocidin - correlated with biotype and virulence

**Heat-stable leucocidin - correlated with biotype and virulence