Abstract:
The distribution of mucous secreting goblet cells was examined in the gastrointestinal tracts of three
insectivores namely: Acomys spinosissimus (Southern African spiny mouse), Crocidura cyanea (Reddish
gray musk shrew) and Amblysomus hottentotus (Hottentot golden mole) in order to improve our understanding
of the quality and composition of the protective intestinal biofilm. Intestinal tracts were fixed
and processed to wax for histology. Serial transverse sections were stained using alcian blue-periodic acid
Schiff, alcian blue-aldehyde fuchsin and alcian blue-high iron diamine techniques. Photomicrographs of
the stained sections were analyzed by quantifying the number of goblet cells containing mucins per mm2
in the surface epithelial or crypt areas. Neutral mucins predominated in the gastric epithelium of all three
insectivores, while sialomucins were absent in the stomach of C. cyanea. In all three species, goblet cells
producing a mixture of neutral and acid mucins were most abundant throughout the intestinal tract as
were cells secreting a mixture of sulfomucins and sialomucins. However, differences between the insectivore
species were observed in the qualitative expression and distribution of mucins throughout the
intestinal tract. Similarities between the insectivores of this study and other distantly related species
suggest that mixed mucin goblet cells are essential for the formation of the biofilm, irrespective of their
diet or taxonomy.
