
 Fig . 10. 
 In ovo  antiviral efficacy of SB239063 against BPXV. ( A ) Determination of the LD 50  of SB239063. LD 50  was determined by inoculating 5-fold serial dilutions of SB239063 (concentration ranging from 100 to 0.16 μg/egg) in 10 days old embryonated SPF eggs, in a total of 100 μl volumes via CAM. Eggs were examined for the viability of the embryos up to five days post-inoculation to determine the LD 50  by the Reed-Muench method. ( B )  In ovo  antiviral efficacy (EC 50 ) of SB239063. SPF embryonated chicken eggs, in triplicates, were inoculated with 2-fold dilutions (10 to 2.5 μg/egg) of SB239063 or DMSO via CAM route, followed by infection with BPXV at 100 EID 50 . At 5 days post-infection, eggs were examined for pock lesions and/or death of the embryos. EC 50  was determined by the Reed-Muench method. The values are means ± SD and representative of the result of at least three independent experiments.