TABLE 5.

Replication and lethality of H5N1 swine influenza viruses in chickens after i.n. inoculationa

VirusNo. of chickens with manifestationVirus replication in organ on day 3 p.i. (log10 EID50/g)Virus shedding on day 3 (log10 EID50/ml)
S/D/totalbSC/totalcLungBrainKidneySpleenPancreasBursaPharynxCloaca
SW/FJ/010/7/7/7.5 ± 0.77.3 ± 1.16.8 ± 0.16.6 ± 0.67.7 ± 0.56.7 ± 0.82.3 ± 1.51.1 ± 1.1
SW/FJ/030/0/77/73.5 ± 0.5d1.2 ± 0.3d1.5 ± 0.7d1.3 ± 0.5d1.8 ± 0.5d1.1 ± 0.8d<0.5<0.5
R-SW/FJ/010/7/7/6.1 ± 0.36.0 ± 1.15.0 ± 0.45.1 ± 0.35.3 ± 0.55.7 ± 0.72.4 ± 0.71.3 ± 0.9
R-SW/FJ/030/0/77/73.5 ± 0.3d0.8 ± 0.3d1.7 ± 0.9d1.3 ± 0.1d1.2 ± 0.80.8 ± 0.3d<0.5<0.5
SW/FJ/01-03PB21/6/71/76.8 ± 0.76.1 ± 1.05.3 ± 1.04.8 ± 1.24.6 ± 1.04.1 ± 1.01.9 ± 1.10.7 ± 0.5
SW/FJ/01-03HA0/7/7/7.4 ± 0.17.0 ± 0.46.8 ± 0.64.9 ± 0.56.4 ± 1.16.0 ± 1.62.1 ± 0.91.0 ± 0.8
SW/FJ/01-03M0/7/7/6.2 ± 0.45.4 ± 1.45.9 ± 0.35.6 ± 0.65.1 ± 0.85.9 ± 0.32.3 ± 0.61.4 ± 0.9
SW/FJ/01-03NS0/0/77/72.7 ± 0.1d<0.52.2 ± 0.2d2.0 ± 0.1d0.8 ± 0.3d<0.5<0.5<0.5
SW/FJ/03-01PB20/0/77/72.4 ± 0.40.7 ± 0.32.0 ± 0.11.9 ± 0.40.8 ± 0.3<0.5<0.5<0.5
SW/FJ/03-01HA0/0/77/72.6 ± 0.4<0.51.9 ± 0.42.1 ± 0.20.7 ± 0.3<0.5<0.5<0.5
SW/FJ/03-01M0/0/77/72.8 ± 0.41.3 ± 0.82.3 ± 0.12.4 ± 0.51.8 ± 0.30.7 ± 0.7<0.5<0.5
SW/FJ/03-01NS2/5/72/74.3 ± 0.32.4 ± 0.1e3.7 ± 0.3e3.8 ± 0.3e2.6 ± 0.61.8 ± 1.11.2 ± 1.01.2 ± 0.9
  • a Six-week-old SPF chickens were inoculated i.n. with 106 EID50 of each virus in a 0.1-ml volume; on day 3, three birds in each group were euthanized, and virus was titrated in samples of lung, bursa, kidney, brain, pancreas, and spleen in eggs. The lower limit of virus detection was 0.5 log10 EID50 per gram of tissue. Pharyngeal and cloacal swabs were collected from all birds on day 3. <0.5, virus was not detected in that sample. Data are means ± standard deviations.

  • b S/D/total, numbers of chickens that were sick (S) and died (D) as well as total number of chickens during the observation period. Birds that showed disease signs, such as depression and ruffled feathers, but recovered at the end of the observation were counted as sick animals.

  • c SC/total, number of chickens that seroconverted/total number of chickens at the end of the observation period. /, all birds died by the end of the observation period.

  • d P < 0.01 compared with the titers in the corresponding organs of the SW/01- or R-SW/01-inoculated chickens.

  • e P < 0.05 compared with the titers in the corresponding organs of the SW/03- or R-SW/03-inoculated chickens.