Study was made to determine whether vaccination of cattle against pseudorabies (PR; Aujeszky’s disease) affords protection upon subsequent intranasal challenge exposure with virulent virus. Because immunity is short-lived, cows can get infected fairly soon (often less than 6 months) after recovering from the disease. In phase 1, 10 sheep were inoculated with high doses of BHV1 and kept in close contact with 5 sheep and 5 calves. In some animals virus multiplication was followed by severe leucopenia lasting several weeks. Malignant catarrhal fever (MCF), a fatal lymphoproliferative disease of ruminant species including domestic cattle and wild living ruminants, is caused by gammaherpesvirus usually associated with malignant catarrhal fever viruses (1). In the described situation different transmission routes for virus seemed possible. The virus also affects endangered bovine species like mithun (Bos frontalis) and yak (Poephagus grunniens).
Out of the 948 bovine sera samples, 303 (32.0%) had antibodies to N. With the currently available diagnostic tests it is not possible to identify animals which have a latent BHV-1 infection. Binding was localized to a 20 bp region of the XhoI-XbaI fragment by EMSA and Exonuclease III footprinting. Inactivated vaccines are not as efficacious as modified live virus (MLV) vaccines. Marker vaccines allow the distinction between vaccinated and naturally infected animals. Consequently, these manifestations are referred to as wildebeest associated (WA-MCF) and sheep-associated (SA-MCF) MCF, respectively (Brown et al., 2007).