Genomic and Virulence Investigations of a Novel Porcine Deltacoronavirus Strain Identified in South Korea

Figure 4

Virulence of PDCoV strains in neonatal piglets. (a) Clinical significance scores (CSS) of each group. The CSS of individual pigs from each group was measured using the scoring criteria for diarrheal severity: 0, normal and no diarrhea (mean Ct values > 35); 1, mild and fluidic feces; 2, moderate mucus to watery diarrhea; 3, severe watery and projectile diarrhea (mean Ct values < 20); 4, death. (b) Survival curves. Individual piglets were monitored, and the survival rates of each group until 7 DPI were plotted. (c) Fecal PDCoV shedding profile of each group. PDCoV RNA titers (log₁₀ genomic copies/ml) in rectal swaps at the indicated sampling time points were determined using rRT-PCR. (d) PDCoV distribution in the intestinal tissues. PDCoV RNA loads (log₁₀ genomic copies/ml) in each intestinal tissue collected at necropsy (performed upon death or after euthanasia at 7 DPI) were determined using rRT-PCR. The mean values of each group at each time point are presented, and error bars denote the SDM. P values were calculated by comparing the data between the KNU-1607 virus- and GNU-2105 virus-inoculated groups. ; .

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