Fig. 2

At necropsy, lungs of the control (a) and HP-PRRSV-infected (b) animals in the study were examined for macroscopic (gross) pathology. The average lung gross scores were evaluated according to the previous scoring system which estimates the percentage of lung affected by pneumonia in the two groups (n = 5). The difference of average lung gross scores between lungs of the control and HP-PRRSV-infected animals was presented (c). Data are presented as mean values ± SD. Asterisks indicate significant differences (**p < 0.01) between infected and control groups