Arch Virol (2002) 147: 2453–2463
Prevention of transplacental infection of bovine foetus
by bovine viral diarrhoea virus through vaccination
J. R. Patel
, R. W. Shilleto
, J. Williams
, and D. C. S.Alexander
Intervet UK Ltd., Huntingdon, U.K.
Mauchline, Scotland, U.K.
Received November 21, 2001; accepted June 12, 2002
Published online October 7, 2002
Summary. 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
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.
Bovine viral diarrhoea virus (BVDV) is an economically important ubiquitous
is often sub clinical with a few exceptions of a severe disease, involving throm-
bocytopenia, bloody diarrhoea, haemorrhages and occasionally death (see Corapi
et al. ) caused by the non-cytopathic biotype of BVDV. Although both cyto-
pathic (CP) and non-cytopathic (NCP) biotypes of BVDV occur naturally, only
the NCP biotype has been recovered from cases of aborted or still born foetuses
or live born calves with persistent NCP BVDV infection . The prevention of
transplacental BVDV infection at this stage of pregnancy is, economically and
epidemiologically, an important goal in view of devastating production losses
through abortions and the fact that persistently infected (PI) animals are the main
source of BVDV transmission as they shed large amounts of virus in their nasal
mucus [1, 6; present data].
Theneed toblocktransplacental infectionthroughvaccinationhasbeenappar-
ent for a long time . It has also been recognised that inactivated vaccines with