Comparison of Immune Responses in Pigs Infected with Chinese Highly Pathogenic PRRS Virus Strain HV and North American Strain NADC-20

Fig. (3) Viremia and PRRSV-specific ELISA Ab profiles after PRRSV infection.(A) PRRSV viral RNA in the serum was determined by real time RT-PCR. (B) Pig serum was assayed for PRRSV-specific antibodies with IDEXX HerdCheck ELISA. The threshold for seroconversion was set at a sample-to-positive (s/p) ratio of 0.4 according to manufacturers’ instructions. Each bar represents the average of five pigs ± SEM. *p<0.05.