Replication of very virulent infectious bursal disease virus in primary cells of the chick embryo chorioallantoic membrane

Infectious bursal disease (IBD), an immunosuppressive viral disease, causes significant losses to the poultry industry either by causing high mortality in an acute disease or as a consequence of immunosuppresion (van den Berg, 2000). The IBD virus (IBDV) can infect and grow on various primary cell cultures of avian origin and certain cell lines of mammalian origin. Tissue culture commonly used to propagate IBDV is chicken embryo fibroblast (Lukert and Davis, 1974) or chicken embryo kidney or baby hamster kidney (El-Ebriary et al., 1997) or ovine kidney (Kibenge and MuKenna, 1992) or normal chicken lymphocytes, B-cell lymphoblastoid or rabbit kidney (Rinaldi et al., 1972), baby grivet monkey kidney and M4-104 cells (Jackwood et al., 1987). Vero cells are fibroblast like cells fromthe kidney of a normal adult African green monkey (Peilin et al., 1997). Isolation and propagation of very virulent infectious bursal disease virus (vvIBDV) from field strain in primary or secondary cell cultures of chicken embryo origin were found to be very difficult, this poor adaptation of vvIBDV in cell cultures may due to the strain differences in field viruses (Mannan et al., 2009). Recently, a longterm cell culture embryo chorioallantoic membrane (CAM) cells developed from specific pathogenic free (SPF) eggs has been established in our laboratory. Its ability to support replication of the vvIBDV was examined in this study.