Fig. 5.

Rectal temperatures, viremia assessment and pathological examination of five pigs in each group challenged with HP-PRRSV (HuN4). a Rectal temperatures were recorded after challenge; b Viral RNA in serum was detected at 0, 7, 10, 14, 21 and 28 DPC; c The pigs were sacrificed at 28 DPC, and lung tissue samples were examined using hematoxylin and eosin staining (H&E). Data are shown as mean ± SD for five pigs per group; Scale bar: 200 μm