3.3 Growth characteristics of YNG strain comparing with other
variant strains
One-step growth curve experiment, CPE observation, and TCID50 assay were
conducted to analyze the growth characteristics of these PRV strains
aforementioned in PK15 and Vero cells, with YNG strain as the control.
The viral copies were determined according to the standard curve: lg
[virus copies] = -0.2293x+9.832, r2=0.9963. As
shown in Fig. 3 , YNG strain exhibited a similar growth curve as
that of YNP strain both in PK15 and Vero cells. The virus titers of YNG
and YNP strains in PK15 and Vero cells at the 36 hpi were
107.14, 106.88 and
106.80, 106.75TCID50/mL, respectively (Fig. 3 ). Likewise,
there was no obvious difference of CPEs in PK15 and Vero cells triggered
by distinct PRV strains, suggesting that YNG strain should be a PRV
variant.