Figure 2

Timeline visualizing chronological steps of experimentation: The colored timeline shows the day of hatching after incubation (d0–d14). Breeding of the fertilized eggs started at day 0. Eggs were opened at day 3 and in vitro cultured tumors transferred on the CAM at day 7. Solid tumors were than analyzed from days 12 to 14 using ultrasonography. Of the 1197 eggs evaluated, 74% (n = 866) were fertilized and showed viability day 3 50% (609 eggs) successfully inoculated a tumor at day 11 not dropping out due to luxation, insufficient ingrowth or death of the embryo. Of the 186 eggs with solid tumors evaluated for ultrasonographic imaging, 100 eggs (54%) were suitable for sufficient ultrasonographic visualization.