Prevention of transplacental infection of bovine foetus by bovine viral diarrhoea virus through vaccination.

Results are presented for an experimental validation of the efficacy of an EU licensed, inactivated bovine viral diarrhoea virus vaccine (Bovilis BVDV). This study was designed to assess the quality of efficacy 6 months after a single course of vaccination (two intramuscular doses a month apart). A natural challenge at about 87 days of gestation by 3 persistently infected carrier heifers rapidly infected all experimental heifers. This resulted in transplacental BVDV infection of all 7 unvaccinated dams whereas 11 immunised dams produced 9 live-born calves and 2 aborted foetuses from which no BVDV could be recovered.