Comparative Collagen Distribution in the Small Intestine of Eidolon Helvum and Manis Tricuspis

Abstract

The African tree pangolin has no teeth but consumes a highly tough and chitinous diet while the bat is frugivorous; this study was designed to compare the morphological adaptations of the small intestine of both mammals by investigating the collagen distribution and hydroxyproline/collagen content of their duodenum and ileum histologically and spectrophotometrically respectively. Ten animals each of both sexes were used. Portions of their small intestine were either fixed for routine histologic processing or homogenized and assayed for the hydroxyproline assay. Histological staining reveal that the collagenous distribution of duodenal submucosa and support of the villus core of the ileum is more prominent in the Pangolin than in the Bat. Data from the hydroxyproline colorimetric assay reveals that the Pangolin has significantly (p = 0.00042) higher total collagen content than in the Bat. It is concluded that the Pangolin has evolved a higher expression and distribution of collagen in their small intestine as a mechanism of coping with their tough diets despite the lack of teeth.