Figure 2

Ileal lesion severity at days post-inoculation 21. Panels A and B represent macroscopic lesions in non-infected pigs (NC, black), non-vaccinated Lawsonia intracellularis inoculated pigs (PC, white), and vaccinated Lawsonia intracellularis inoculated pigs (VAC, blue), while panels C through F describe microscopic lesion severity. A Frequency of macroscopic lesion severity score. B Average lesion length (cm) of lesion, if any. C Inflammation score wherein 0  =  none/minimal, 1  =  mild, 2  =  moderate, and 3  =  severe. D Proliferation of crypts, wherein 0  =  none/minimal, 1  =  mild, 2  =  moderate, and 3  =  severe. E Lesion distribution score, wherein 0  =  none, 1  =  focal, 2  =  multifocal, and 3  =  diffuse. F L. intracellularis immunohistochemistry (IHC) scoring, where 0  =  no antigen stain, 1  =  1–25% of crypts, 2  =  26–50% of crypts, 3  =  51–75% of crypts, 4  =   > 75% of crypts positive for antigen.