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

Fig. (2) Lung pathology, thymus atrophy and lung inflammation caused by PRRSV infection.(A) Macro lung pathology score. (B) Histopathological score. Thymus weight (C) and lung weight (D) to body weight ratios after virus infection. Each bar represents the average of five pigs ± SEM. *p<0.05.