3.4 Positive detection of viral RNA in embryos and
ducklings
101 vitelline membranes, 91 dead embryos and 263 duckling spleen samples
were collected in the artificial infection experiment, and qPCR was used
to detect viral RNA. Among the samples detected, 18 of 82 yolk membrane
samples, 33 of 88 dead embryo samples, and 139 of 141 duckling spleen
samples were detected positive for N-DRV. When these two infection
methods, the positive rate of viral RNA in the oral administered group
was higher than that in the intramuscular injection group. No virus RNA
was detected in the control group. Detailed detection data was presented
in Table 2.