Figure 3

Detection of IPNV RNA in Vero and HE cells inoculated with IPNV. Cell culture flasks with Vero cells or HE cells were inoculated with IPNV-1p (TCID₅₀ ml^-1 10⁴) and incubated in parallels at 25°C (a and b) and 37°C (c and d). At the indicated time points, cell monolayers were harvested, nucleic acids extracted, and IPNV RNA detected by RRT-PCR. After one week of incubation, the cells kept at 37°C were passaged onto new flasks and cocultivated (1:1) with noninfected cells. The numbers in parenthesis indicate the passage number. The Ct value is an average of duplicates and n=1. n.d.=not detected.