Figure 4

Diffusion of modified particles and labeled TGEV in 3-day and 3-week mucus at 4 °C and 37 °C. A Representative picture of diffused particles (green) in mucus (red) in the “dispersed” stage (scale bar = 50 µm). B Representative picture of diffused particles (green) in mucus (red) in the ‘settled’ stage (scale bar = 50 µm). C: Individual mean diffusion values ± SD of three animals per age group at 4 °C and 37 °C at 10 and 30 min are plotted as scatter graphs with bars. Statistically significant differences were determined by two-way ANOVA. Small alphabets (a, b, c, d) represent significant differences (p < 0.05) between particles/TGEV (Tukey’s multiple comparison post hoc test). Capital “A” means significant differences (p < 0.05) between age groups (Šídák’s multiple comparison post hoc test). Detailed diffusion comparisons between the age groups and particles/virions at 10 and 30 min are presented in Additional file 1 (Figure 4; Annex A and B).