2.6. Intestinal histology
Intestinal tissue samples were stained (hematoxylin and eosin and
periodic acid–Schiff stains) following standard paraffin embedding
procedures (Uni et al., 1998; Xu et al., 2003) and examined using a
microscope with an ocular micrometer. Ten intact crypt villi in each
sample were selected to measure the villus height, crypt depth, villus
diameter and mucosa depth. In addition, five integral villi in each
sample were chosen to determine the number of intestinal epithelium
lymphocytes and goblet cells per 100 intestinal epithelium cells. The
villus height and crypt depth were calculated as described by Nabuurs
et al. (1993), the villus diameter was measured at the widest part of
the villus and the mucosa depth was calculated as the vertical
dimension from the epithelial mucosa to the muscularis mucosae
(these layers were included).