Radiographic Anatomy and Barium Sulfate Contrast Study of the Gastrointestinal Tract of Eastern Box Turtles (Terrapene carolina carolina)
This study describes the normal radiographic anatomy, transit, and emptying times of the gastrointestinal tract in healthy eastern box turtles (Terrapene carolina carolina) administered 15 ml/kg barium sulfate diluted to 30% weight per volume via orogastric gavage. Three-view radiographic series (vertical beam dorsoventral, horizontal beam latero-lateral, and horizontal beam rostrocaudal views) were obtained prior to contrast administration, and following contrast administration at 0, 20, 40, 60, and 90 min, 2, 4, 8, 12, and 24 hours post administration, and every 24 hours thereafter until all contrast was eliminated. Vertical beam dorsoventral and horizontal beam latero-lateral views were of excellent quality to identify gastrointestinal structures. The horizontal beam rostrocaudal view immediately post-contrast administration provided gastric and pyloric identification but had lesser diagnostic use at later time points due to anatomic superimposition. The gastrointestinal tract was composed of a tubular stomach, a pyloric sphincter near the midline, a duodenum with a cranial flexure in the right cranial coelomic cavity, small intestines within the right coelom, a small cecal bulb, and a transverse and descending colon. Contrast media entered the large intestine by 24 hours in all turtles, and a pyloro-colic indentation was noted at the proximal descending colon. The large intestinal emptying was highly variable due to the interindividual variability of contrast sequestration within the cecal bulb. This is the first study to detail the gastrointestinal anatomy, transit, and emptying times in healthy eastern box turtles, and to evaluate the horizontal beam rostrocaudal view for gastrointestinal contrast studies in any chelonian.