Fig. 1. Photomicrographs of liver (a) and caecum (b) from a study Siberian hamster. The liver displayed a normal hepatic lobular histology, with observable portal triads (p.t.) and central veins (c.v.), and minimal to no evidence of inflammation, fibrosis or neoplasia. Similarly, the caecum also displayed normal histology, with the mucosa containing normal intestinal glands of regular height, with minimal inflammation, fibrosis or neoplasia. Additionally, the remainder of the gastrointestinal tract (including non-glandular stomach, glandular stomach, small intestines and colon) and gallbladder were also histologically normal (not shown). Warthin–Starry-stained sections also failed to reveal the presence of any spiral bacteria in these sections. Overall, these photomicrographs are representative of the gastrointestinal tracts and hepatobiliary system in all the Siberian hamsters examined in this study, except for the presence of a squamous papilloma in the non-glandular stomach in one hamster, and hemangiosarcoma in the liver of another hamster. H&E stain. Bars, 100 µm (a); 50 µm (b).