DIAGNOSTIC COMPATIBILITY OF A THYMIDINE KINASE, INVERTED REPEAT, GI, AND GPX MODIFIED-LIVE GENE-DELETED PRV VACCINE WITH 3 DIFFERENTIAL ELISAS

The differential pseudorabies virus (PRV) vaccines currently in use in the USA have deletions of the genes coding for the glycoprotein I (gI ) and/or glycoprotein X (gpX). The absence of gI and/or gpX allow for the serologic differentiation of vaccinated swine from PRV-infected sw ine using differential enzyme-linked immunosorbent assays (ELISAs). A newly developed pseudorabies vaccine virus has 4 deletions of the vira l genome: the genes coding for gI, gpX, and thymidine kinase and a por tion of the repeat region to attenuate the virus. The purpose of this work was to evaluate the diagnostic compatibility of the gI/gpX gene-d eleted vaccine with 3 differential vaccines and 3 differential ELISAs currently in use. Pigs vaccinated 3 times with the gI/gpX gene-deleted vaccine remained seronegative on the 3 differential ELISAs tested. Pi gs previously vaccinated with either a gI or gpX gene-deleted vaccine and then vaccinated with the gI/gpX gene-deleted vaccine remained sero negative on the respective gI or gpX differential assay.