The topography and gross anatomy of the abdominal gastrointestinal tract of the Persian Squirrel (Sciurus anomalus)

The Persian Squirrel (Sciurus anomalus) is the only member of the Sciuridae family found in the Middle East. It is herbivorous, feeding mostly on pine acorns and other seeds and fruits. It is a wild animal nesting in forest trees, although it is frequently found close to city gardens and parks. As Persian squirrels are also found in homes as "companion animals", veterinarian assistance may be sometimes required; this is a good reason to gain more specific knowledge of the anatomical features of this animal. Due to the scantiness of relevant literature, we carried out this study with the aim to provide further information on the topography and gross anatomy of its abdominal gastrointestinal tract (GIT). Seven animals of this species were utilized to measure the length, content weight and area surface of the relative segments of the abdominal GIT. The stomach is unilocular, lined with glandular epithelium; the small intestine is divided into duodenum, jejunum and ileum. The cecum is situated on the right side of the abdominal cavity and lacks the vermiform appendix observed in some rodents. The ascending colon is extensive, consisting of two loops and two straight parts forming a unique topographic arrangement, closely resembling the ascending colon of the horse. The transverse colon connects the ascending and the descending colon located on the left side of the abdominal cavity, and shows a distinct sigmoid flexure before entering the pelvic cavity. Overall, the in situ examination and the relative measurements of the various parts of the abdominal GIT suggest that the ascending colon is the main fermentation chamber in the Persian Squirrel.