Figure 1 .
 1M. bovis infection reduced the viability of EBL cells. Cell viability after M. bovis infection at different multiplicity of infection (MOI) of 10, 20, 30, 50, 60 and 80 and different time of 24 h, 48 h and 72 h, respectively, were detected using MTT assay. It was determined by calculation that the half-maximal inhibitory concentration (IC50) at 24 h, 48 h and 72 h was 60, 60 and 50 MOI, respectively. The **data** are expressed as mean ± SEM. Experiments were repeated at least three times. *** p < 0.001 indicated statistical significance.