FIG 4.

Pathogenicity of the recombinant PEDV N93/95A and icPC22A strains in Gn piglets. (A) Fecal consistency scores of pigs from preinoculation to 16 dpi. Fecal consistency was scored as follows: 0, solid; 1, pasty; 2, semiliquid; and 3, liquid. Each dot represents the score of an individual pig; each line indicates the mean score of a group. Scores of ≥2 and 3 were considered diarrhea and severe diarrhea, respectively. All pigs in the icPC22A group died by 6 dpi. (B) PEDV RNA (N gene) shedding titers in rectal swabs from preinoculation to 16 dpi. Each symbol represents the titer of an individual piglet; each line indicates the mean value from a group. The dashed line at 4.8 log₁₀ copies/mL indicates the detection limit. (C) Fecal infectious PEDV titers of pigs postinoculation. Each symbol represents the titer of an individual piglet; each line indicates the mean value from a group. The dashed line at 1.3 log₁₀ TCID₅₀/mL indicates the detection limit. (D) Survival curves of pigs after inoculation with N93/95A or icPC22A by 18 dpi. (E) Immunohistochemistry staining of PEDV N proteins in jejunum and ileum sections from piglets euthanized at 3 dpi (magnification, ×100). (F) VH/CD ratios for piglets. Ten villi of each intestinal section were measured. Data are shown as mean ± SD. Groups with significant differences (P < 0.05) are indicated with different letters.