Cellular response to BoHV-1 observed in vaccinated cattle. Cellular immune response at 7 dpv detected by (a) Lymphocyte proliferation test (LPT). Values are expressed as the percentage of animals in each treatment group exhibiting significant (LPT response >3) lymphocyte proliferation after vaccination at 7 dpv. (b) IFNγ at 7dpv. Values are expressed as pg/ml. References in this figure are as described in Figure 3.