Fig. 7

Mass-type IBV isolates recovered from Western Canadian layer flocks increase macrophage numbers in lungs. The representative images of lungs stained for IBV antigens and macrophages (a) and quantitative data for IBV antigens (b), macrophages (c) and IBV antigen positive macrophages (d) at 4 dpi are depicted. The error bars represent the ± SEM. Statistical significance: *p < 0.05, **p < 0.01, ***p < 0.001