TABLE 2.
Virulence of PRV strains in the chicken embryo eye model
| Strain | LD50a (PFU) | Mean time to deathb (h) |
|---|---|---|
| BeBlu | 5.8 × 101 (31c) | 46 (45) |
| BaBlu | 5.6 × 103 (56) | 68 (38) |
| PRV-99Blu | 2.0 × 102 (31) | 61 (43) |
a
Determined by the graphic interpolation method of Reed and Muench as described in Materials and Methods. Animals surviving beyond 168 h postinjection were considered to have survived the virus challenge.
b
Determined by using an inoculum of 105 PFU. Animals were monitored at least every 6 h for survival. Animals which survived the challenge were not included in the determination.
c
Number of animals tested.