(a) Diagnosis: only now used if cell cultures do not work e.g. African Horse Sickness virus in suckling mice.

(b) Pathogenesis studies: to prove that a particular virus causes a specific disease, Koch’s postulates, and to establish which tissues are richest in virus for diagnosis.

(c) Vaccine development: to prove efficacy. Laboratory animals may be used if a lab. animal model is available and appropriate, before trials in the target species.

(d) Serology: horses, rabbits & goats used to provide virus-specific antibodies. Mice for monoclonal antibodies.