IFNG and infection: As summarized above (Section 5.2, Section 5.3 and Section 5.4), infection with virulent BoHV-1 isolates (Iowa, IBRV HB06) triggered increased serum levels of IFN-γ [101,102], as well as attenuated BoHV-1 candidate vaccines (tmv; a three-gene-mutated BoHV-1 vaccine virus), BoHV-1 gEdel (a gE-deleted vaccine virus) [115], IBRV HB06-derived mutant BoHV-1 gG−/tk−, and BoHV-1 gE−/tk− [102].