2.2. Preliminary confirmation and virus isolation
DNA was extracted from scab suspensions using QIAGEN Blood and tissue DNA isolation kit. Isolated DNA was subjected to CaPV-specific PCR as described earlier (Ireland and Binepal, 1998). After preliminary confirmation, Vero cells grown in EMEM supplemented with antibiotics and 10% fetal calf serum were infected with filtered scab suspension using the adsorption method. The cells were observed daily for the appearance of cytopathic effect (CPE). After preliminary isolation of LSDV into Vero cells, further propagation was continued up to seventy passages (P70).