SEM studies of adherence of XXXX to the gastrointestinal tract of @entity1 @entity19 .

@entity1 @entity1568 @entity19 @entity5132 @entity375
In our earlier investigations it has been shown that the gastrointestinal (GI) tract of the @entity1 @entity19 (4-5 days old) can be colonized following a single intragastric challenge with @entity5132 . This makes it possible to investigate the sequence of events which occur during colonization of the GI tract by this opportunistic @entity375 . Two strains of @entity5132 , CA 30 and NS 33, which were shown in earlier studies to differ markedly in their ability to persist in the GI tract were examined. The SEM was used to reveal the location of the @entity375 and their structural association with the surface of tissues of the gut at early times after intragastric inoculation. Animals were sacrificed after challenge, the GI tract was removed from each @entity19 and subdivided into the stomach, upper intestine, mid-intestine, ileum, cecum and large bowel. The number of colony forming units was determined by homogenizing these segments and plating them out on sabouraud's dextrose agar. The microenvironment of each segment was preserved by freezing samples in liquid @entity1568 prior to processing for the SEM. The distribution and level of counts of the strains studied in the GI tract were comparable during the three week period. Both strains of @entity5132 associated with the secreting epithelium and the keratinized epithelium of the stomach. @entity375 also associated with the mucus layer and the epithelial surface throughout the GI tract. Those @entity375 adhering to the epithelial surfaces of the GI tract were frequently covered by a layer of mucus which may aid in colonization.
