Viral loads in spleens from chickens experimentally infected with MDV-1. Chickens were inoculated with 2,000 PFU of RB1B (n = 36). Spleens were collected from MDV-1-infected and uninfected chickens at 3, 7, 10, 14, 21, 28, and 35 d.p.i., and four samples were prepared at each time point. Viral loads in the spleens were determined by real-time PCR targeting the meq gene. The results are shown as ratios between concentrations of the meq and chicken β-actin genes in the spleens. Error bars indicate standard deviations.