title: Aujeszky's disease virus strains with peculiar features.
abstract: Aujeszky's disease (AD) virus strains isolated from weak colostrum-deprived piglets were investigated for virulence in rabbits. Most of them (5 out of 9 investigated) proved avirulent. As clinical symptoms of AD were not observed during this period on the farms of origin, one can assume that the strains had a particular affinity for the pig fetus. It is proposed that the strains may be a result of recombination between the attenuated strains MK-35 (gI-) now in use as a live vaccine and MK-35 (gI+), used as a live vaccine until 3 years ago, as well as between the vaccine strain and a wild-type strain of AD virus, followed by the acquisition of tropism for the reproductive system. Virulent as well as avirulent strains were isolated in the same herd. The evaluation of a highly immunogenic killed AD vaccine in this complicated situation is recommended.
authors: Central Veterinary Research Institute, Sofia, Bulgaria.
authors: A D
authors: AD
authors: Motovski
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D011558:Herpesvirus 1, Suid / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000472:pathogenicity*; D011557:Pseudorabies / Q000821:virology*; D022421:Pseudorabies Vaccines; D011817:Rabbits / Q000821:virology*; D011995:Recombination, Genetic; D013552:Swine; D013553:Swine Diseases / Q000821:virology; D014613:Vaccines, Attenuated; D014765:Viral Vaccines / Q000235:genetics; D014774:Virulence
chemical_list: D000914:Antibodies, Viral; D022421:Pseudorabies Vaccines; D014613:Vaccines, Attenuated; D014765:Viral Vaccines