- Vac (P): vaccination of suckling pigs against M. hyopneumoniae. (N): no vaccination
- Acc (P): gilts have contact to living animals during their acclimatisation. (N): no contact to living animals
- Suc (P): duration of suckling period is 21Â days. (N): suckling period is extended to 28Â days
- Con (P): growers have no contact to finishing pigs during restocking of compartments. (N): contact between different age groups
- Inf (P): pigs do not suffer from co-infections. (N) presence of co-infections
- *Severity of disease is defined as the average proportion of days that each pig is acute or chronic infectious during a particular period (e.g. only nursery period. only fattening period or whole life time)