Fig. 4.

Quantification of virus in the nasal swab samples. To determine viral shedding in the respiratory tract, nasal swab samples were collected at 1, 2, 3, and 4 days post inoculation and suspended in 1 mL of phosphate-buffered saline. CIV RNA was quantified by matrix gene-based real-time reverse transcriptase polymerase chain reaction. The log₁₀EID₅₀ equivalents were determined with the use of rRT-PCR. *p < 0.05 by ANOVA with Dunnett’s post hoc test compared with vaccinated groups.