Fig. 6. Pathologic changes induced in the inoculated chicken embryos with the positive IBV swab suspensions. (A) Percentage of embryo gross lesions, (B) Normal embryo of the control group, (C) Curled and dwarfed embryo inoculated with vaccinated-unchallenged cloacal swab, (D) Curled and dwarfed embryo inoculated with vaccinated-challenged cloacal swab.