Fig. 1. PDCoV agglutinates rabbit erythrocytes. (A) PDCoV were treated with various concentrations of trypsin and then mixed with rabbit erythrocytes for HA assay. (B) PDCoV were treated with different concentrations of neuraminidase and then mixed with erythrocytes at 37°C for 30 min for HA assay. (C) Rabbit erythrocytes were incubated with trypsin and neuraminidase prior to HA testing. Non-treated virus was used as the mock virus.

PDCoV, porcine deltacoronavirus; HA, hemagglutination.