Light and confocal microscopy of E. coli O157:H7 localised adherence and micro-colony formation at the terminal rectum mucosa of rectally inoculated young lambs at day 3 (Lamb 5: A, C and E) and 14 (Lamb 9: B, D and F) after inoculation. Open circles denote localised adherence. Staining: (A and B) = Haematoxylin and Eosin; (C and D) = Meyer’s haematoxylin (terminal rectum-blue), immunoperoxidase (E. coli O157-brown); (E and F) Dapi (blue) = nuclei; FITC (green) = E.coli O157. Magnification (AandC) = 400×, (B and D) = 200×. Bar (E) = 20 μm, (F) = 18 μm.