Fig. 4

Immunohistochemical examination of the brain at 5 dpi. The KM-H, KM-M and KM-L represent the PRV-infected groups which were treated with kaempferol at doses of 240, 160 and 80 mg/kg• body weight, respectively. ACV, the acyclovir-treated group (160 mg/kg• body weight). A DAB chromogen substrates were used for antigen visualization. The SABC staining positive cells mainly showed brownish-yellow (indicated by arrows), and the section Background mainly showed light yellow. Each tissue undergoes three SABC stains to check its repeatability. The uninfected–untreated control had no obvious positive cells, and the infected-untreated group had the most number of positive cells. Compared with the infected-untreated group, the number of positive cells in the treated group decreased. B No brownish-yellow cells detected in the uninfected-untreated control were negative; the scattered distribution of brownish-yellow cells in the tissue is less than 5 % indicates mildly positive; the proportion of brownish-yellow cells in the tissue is 5 − 50 % indicates positive; the proportion of brownish-yellow cells in the tissue is greater than 50 % indicates strong positive