Morphology of the large intestine of the pig: haustra versus taenia.

The aim of the present study was to compare the morphological characteristics of the taenia and haustra of the large intestine in pigs. Ten pigs were fed a barley/wheat-based diet for a period of five weeks. Tissue samples were taken from the cecum and the proximal part of the colon at slaughter and processed histologically for determination of crypt volume, depth and density of the crypts, thickness of muscularis externa, and carbohydrate histochemistry. In all parameters examined regional differences in mucosal architecture of the cecum and proximal colon were demonstrated. Apparently, the regional differences in mucosal architecture between taenia and haustra were more pronounced in the cecum than in the proximal colon. The regional variation in mucin characteristics and in crypt parameters could be explained by differences in functional status and/or in the local environment. As all the parameters investigated in this study are not only dependent on sampling site, but also, e.g., on type of diet and its physical form, great care must be taken to obtain tissue from comparable sites in all animals in experimental studies to avoid incorrect conclusions.