S1 gene sequence analysis of a nephropathogenic strain of avian infectious bronchitis virus in Egypt

Abdel-Moneim, Ahmed S; El-Kady, Magdy F; Ladman, Brian S; Gelb, Jack

Chickens vaccinated with H120 (Group A) showed 58.3% protection (7/12) by virus reisolation procedure and 66.6% (8/12) protection by histopathology after challenge with Egypt\F/03 while all control unvaccinated birds (Group B) were not protected (5/5) ( Table 2) . On day four PI, the kidneys of (3/12) birds in group A (vaccinated and challenged with IBV) showed focal lymphocytic infiltration, urates deposition and degenerative changes in renal tubules while birds of group B (unvaccinated and challenged with IBV) showed multifocal lymphocytic infiltration, urates deposition and degenerative changes in renal tubules in 4/5 birds, while only focal lymphocytic infiltration, urates deposition and degenera-Dot-ELISA shows positive reaction in tested (chorioallantoic membrane homogenate) and control positive sample Control +v e Tested sample Control -ve tive changes in renal tubules were observed in 1/5 birds. Birds in group C (vaccinated unchallenged group) did not show any abnormalities (0/12) either in tracheae or kidneys. Immunofluorescenct assay on kidneys of challenged and unchallenged groups showed that all challenged unvaccinated and 3/12 of challenged vaccinated groups possessed kidney immunofluorescence. None of control unchallenged groups possessed kidney immunofluorescence (Table 2 ).