Figure 4.
Dispnoea score. Dyspnoea (score) observed in pigs after experimental infection with influenza A viruses, dpi, days post infection; statistics: asterisk (1 p < 0.05, 2 p < 0.010, 3 p < 0.005, comparison of following groups: a H1N1/1981:H1N1/2006, b H1N1/1981:H1N2/2000, c H1N1/1981:H3N2/2006, d H1N1/2006:H1N2/2000, e H1N1/2006:H3N2/2006, f H1N2/2000:H3N2/2006).