Veterinary recommendations for the handling of equine virus arteritis (EVA) in practical breeding care

The equine virus arteritis (EVA) consistently epidemically varying throughout the different breeds of the horse breeding countries is up to now only of lower significance by means of the typical clinical manifestation as well as an abortion causing factor. The susceptibility of the sexual mature stallions against the equine arteritis virus (EAV) causes different infection response which may lead to some restrictions in their use in natural breeding especially in the artificial insemination. In a certain not precisely predictable part of the stallion population EAV infection will cause a transient or permanent virus presence in the accessorial apparatus of the genital tract with transient or permanent shedding of the virus via seminal secretions. This makes the stallion to one of the dominant factors of the propagation of the field virus. The use of EAV shedding stallions in natural breeding or AI is very risky and only justifiable under certain precautions and additional measurements e.g. in EAV-seropositive or vaccinated mares. A consistent progress in the defeat of the disease can be expected from vaccination of the seronegative stallions with dead or inactivated live vaccines as they are considered to be able to prevent the establishing of EAV shedder status.