Figure 1.

Viral progeny titration in CV‐B4‐infected thymuses. The thymuses of six mice (three offspring born to each of two dams) of each experimental condition (oral virus inoculation at days 10G or 17G, and in the absence of inoculation) were subjected to viral progeny titration, by the plaque assay method, at different post‐inoculation (p.i.) times (day 17 gestation and days 0 and 5 from birth). Data are representative of two independent experiments with n = 3 thymuses per group and per time‐point, in each. Results are plotted as mean titres plaque‐forming units (p.f.u.)/mg of tissue) ± standard deviations.