Additional file 2 of Genetic interference exerted by Salmonella-delivered CRISPR/Cas9 significantly reduces the pathological burden caused by Marek’s disease virus in chickens

Additional file 2. The serum cytopathic effect of Marek’s disease virus on infected chicken fibroblasts. Serum collected from chickens on the 5th week post-challenge was used to treat cultured chicken fibroblasts at a 1:50 dilution. The cytopathic effect was observed after three days of infection.