Figure 6. Quantification of viral loads in different tissues of euthanized ducklings using real-time quantitative RT-PCR (qRT-PCR).

Samples were collected from ducklings challenged with NDRV-TH11 strain at 14 dpc, and their viral copies were then detected by qRT-PCR. (A) Viral loads in blood. (B)Viral loads in the spleen. (C) Viral loads in the liver. The dotted line marks the positive cut-off. The statistical significance of differences in the virus copies between vaccinated and control groups were determined using One-Way ANOVA and Tukey’s multiple comparison tests between groups. (**p < 0.01 vs. PBS group).