Viremia and viral loads in tissue assessment
To determine the duration of viremia and viral loads in different
tissues after treatment with the SD-R vaccine strain, serum samples
collected at dpv 0, 7, 14, 21, and 28 and dpi 3, 5, 7, 10, 14, and 21
and ten tissues of all the piglets were used to detect the RNA copy
number of PRRSV by TaqMan®-based real-time
fluorescence quantitative RT–PCR (Wei et al., 2008).