Pathogenesis and tissue distribution of a variant strain of infectious bursal disease virus in commercial broiler chickens.
The detection of either infectious virus, viral antigen, and/or viral RNA in different tissues of commercial broilers inoculated at 1 day of age with E/Del variant strain of infectious bursal disease virus (IBDV) was investigated at 2, 4, and 6 wk postinoculation (PI). Virus was readily isolated from homogenates of bursa, cecal tonsils, and bone marrow at 2 and 4 wk PI. Virus isolation coupled with immunoperoxidase assay or reverse transcription-polymerase chain reaction for IBDV-specific RNA extended the window of IBDV detection in the bursa of Fabricius to 6 wk PI. Serology indicated an active early virus infection; however, viral pathology was observed later and beginning at 4 wk PI. This study indicates that variant strains of IBDV may be present in commercial broilers longer than previously thought, and cecal tonsils and bone marrow may serve as nonbursal lymphoid tissues supporting virus replication at later time points PI.
Elankumaran
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VA-MD Regional College of Veterinary Medicine, University of Maryland, College Park 20742-3711, USA.
Heckert
R A
RA
Moura
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L
D000818:Animals; D018175:Birnaviridae Infections / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D001853:Bone Marrow / Q000821:virology; D002060:Bursa of Fabricius / Q000821:virology; D002645:Chickens; D007124:Immunoenzyme Techniques / Q000662:veterinary; D007243:Infectious bursal disease virus / Q000302:isolation & purification* / Q000472:pathogenicity; D008221:Lymphoid Tissue / Q000821:virology*; D014066:Palatine Tonsil / Q000821:virology; D011201:Poultry Diseases / Q000175:diagnosis / Q000821:virology*; D012367:RNA, Viral / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013997:Time Factors; D014779:Virus Replication
D012367:RNA, Viral