Ann. Méd. Vét., 2009, 153 (2), pp 88-104 Reduction of the seroconversion incidence against bovine herpesvirus 1
in dairy/beef mixed herds by the repeated administration of inactivated gE deleted marker vaccines.DISPAS M., LEMAIRE M., SPEYBROEK N., BERKVENS D., DUPONT A.Abstract :
A cohort study was conducted in
dairy/beef mixed herds (DBMH) to
assess the efficacy of hyperimmunisation
for the control of bovine herpesvirus 1 (IBR). Two protocols using repeated administrations of vaccine were compared to a positive control group (PCG). Only the primovaccination was different in the hyperimmunised herds : in group 1, live attenuated vaccine
was given firstly intra-nasally then
by intramuscular route, in group 2
an inactivated vaccine was twice
given subcutaneously. Boosters were identical in both groups: inactivated vaccines given subcutaneously about every 6 months.
In the PCG, yearly vaccination of a
part of the animals was the general
rule.
The efficacy of the protocols was
studied by survival analysis considering
times to seroconversion towards the gE glycoprotein. In cattle of group 2, a significantly larger proportion of animals remained seronegative compared
to group 1 and to PCG. The probabilities
of seroconversion were different among groups considering gender and birth cohorts.
Although a reduction of gE seroprevalence was observed in group
1, only group 2 showed a significant
advantage for the control of IBR in DBMH compared to PCG. Get the PDF Contact person : madis@var.fgov.be |