Contributions to study the anatomy of stomach of Bradypus variegatus (Mammalia: Folivora)

Accurate anatomical and physiological knowledge of the stomach of the three-toed sloth is essential for effective clinical, surgical and dietary management, particularly in rehabilitation settings. This study analyzed the holotopy, topography, syntopy, and macro- and microscopic morphology of the stomach in thirteen B. variegatus specimens. Macroscopically, the stomach was located in the cranial, middle and abdominal regions and extended over the xiphoid, hypochondriac, lateral and umbilical regions. It had syntopic relationships with the diaphragm, liver, intestines, uterus (in females), vertebrae, ribs, spleen, pancreas, kidneys and abdominal musculature. The stomach showed distinct structural divisions, including saccular, diverticular and tubular segments, leading to the classification of seven anatomical regions: cranial sac, left and right lateral sacs, ventral sac, diverticulum, glandular pre-pylorus and non-glandular pre-pylorus. Histologically, the cranial sacs were non-glandular and keratinized, whereas the right lateral sac and diverticulum were glandular, the latter possibly involved in absorption. The cranial pre-pyloric region contained oxyntic and zymogenic glands, whereas the caudal pre-pyloric region lacked glands but had a keratinized mucosa. Unique anatomical features included peritoneal recesses, an omental pouch.

Key words
Xenarthra; morphology; foregut; sloth; Bradypodidae