Fig. 2

Immunohistochemistry for “B. canis” (A, B, E, G) and B. pilosicoli (C, D, F, H, I) in canine colon (A-D), canine duodenum (E, F) and porcine colon (G-I). A: Moderate numbers of “B. canis”-immunoreactive bacteria on the luminal surface of the colon. B: Higher magnification from A showing the characteristic spiral-shaped morphology of Brachyspira (arrow). C: Minimal numbers of B. pilosicoli-immunoreactive bacteria on the luminal surface of the colon. D: Higher magnification from B showing the characteristic spiral-shaped morphology of Brachyspira (arrow). E: No detection of “B. canis”-immunoreactive bacteria in the duodenum. F: No detection of B. pilosicoli-immunoreactive bacteria in the duodenum. G: Minimal numbers of “B. canis”-immunoreactive, spiral-shaped bacteria on the luminal surface of the colon of a pig with intestinal spirochetosis associated with the detection of B. pilosicoli by PCR. H: Large numbers of B. pilosicoli-immunoreactive, spiral-shaped bacteria on the luminal surface of the colon of a pig with intestinal spirochetosis associated with the detection of B. pilosicoli by PCR. I: Higher magnification from H showing the characteristic spiral-shaped morphology of Brachyspira (arrow). Immunohistochemistry employing polyclonal rabbit anti-“B. canis”-antibody or rabbit anti-B. pilosicoli-antibody and the avidin-biotin-peroxidase complex method with DAB chromogen and hematoxylin counterstain. Differential interference contrast microscopy. Bars A, C, E, F = 100 μm; B, D, I = 20 μm; G, H = 200 μm