Certain diseases cannot be treated, either because no treatment exists or because they
cause death and loss of production so quickly that treatment is not practical. These diseases
have to be understood and prevented through vaccination and proper management to
minimise their effect on production costs.

The four disease prevention strategies:

1. Increase general resistance – good parasite control, nutrition and reproduction management.
2. Increase specific resistance – vaccination to establish immunity against specific diseases.
3. Decrease exposure – reduce exposure through early treatment, disease testing and culling policies, quarantining of sick animals and good parasite control.
4. Avoid exposure – strict biosecurity policy for testing new animals.
   These diseases must not be introduced onto a farm.